Merge branch 'devel' into pr_remove_macros

The PR branch had merge conflicts with `devel` due to a major compiler
refactoring that extracted type definitions from `compiler/ast.nim` into
a new `compiler/astdef.nim` file.

## Changes

- Resolved conflict in `compiler/ast.nim` by accepting `devel`'s
refactored structure
- Merged 763 commits from `devel` branch (commit range:
`ce6a345..b3273e7`)
- Preserved original PR changes removing deprecated symbols from
`lib/core/macros.nim`

The core PR functionality (removal of deprecated macros API since
v0.18.1) remains intact while incorporating the upstream AST
refactoring.

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---

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.github/dependabot.yml

@@ -1,11 +0,0 @@
-# To get started with Dependabot version updates, you'll need to specify which
-# package ecosystems to update and where the package manifests are located.
-# Please see the documentation for all configuration options:
-# https://docs.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
-
-version: 2
-updates:
-  - package-ecosystem: "github-actions" # See documentation for possible values
-    directory: "/" # Location of package manifests
-    schedule:
-      interval: "weekly"

.github/workflows/bisects.yml

@@ -15,7 +15,7 @@ jobs:
     name: ${{ matrix.platform }}-bisects
     runs-on: ${{ matrix.platform }}
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v5
 
       - name: Install OpenSSL (Windows)
         if: |

.github/workflows/ci_docs.yml

@@ -53,7 +53,7 @@ jobs:
 
     steps:
       - name: 'Checkout'
-        uses: actions/checkout@v6
+        uses: actions/checkout@v4
         with:
           fetch-depth: 2
 
@@ -109,7 +109,7 @@ jobs:
         if: |
           github.event_name == 'push' && github.ref == 'refs/heads/devel' &&
           matrix.target == 'linux'
-        uses: crazy-max/ghaction-github-pages@v5
+        uses: crazy-max/ghaction-github-pages@v4
         with:
           build_dir: doc/html
         env:

.github/workflows/ci_packages.yml

@@ -33,14 +33,14 @@ jobs:
       NIM_TESTAMENT_BATCH: ${{ matrix.batch }}
     steps:
       - name: 'Checkout'
-        uses: actions/checkout@v6
+        uses: actions/checkout@v4
         with:
           fetch-depth: 2
 
-      - name: 'Install node.js'
-        uses: actions/setup-node@v6
+      - name: 'Install node.js 20.x'
+        uses: actions/setup-node@v4
         with:
-          node-version: 24
+          node-version: '20.x'
 
       - name: 'Install dependencies (Linux amd64)'
         if: runner.os == 'Linux' && matrix.cpu == 'amd64'

.github/workflows/ci_publish.yml

@@ -17,14 +17,14 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - name: 'Checkout'
-        uses: actions/checkout@v6
+        uses: actions/checkout@v4
         with:
           fetch-depth: 2
 
       - name: 'Install node.js'
-        uses: actions/setup-node@v6
+        uses: actions/setup-node@v4
         with:
-          node-version: 24
+          node-version: ''
 
       - name: 'Install dependencies (Linux amd64)'
         if: runner.os == 'Linux' && matrix.cpu == 'amd64'
@@ -60,7 +60,7 @@ jobs:
         run: nim c -r -d:release ci/action.nim
 
       - name: 'Comment'
-        uses: actions/github-script@v9
+        uses: actions/github-script@v7
         with:
           script: |
             const fs = require('fs');

.github/workflows/stale.yml

@@ -9,7 +9,7 @@ jobs:
   stale:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/stale@v10
+      - uses: actions/stale@v9
         with:
           days-before-pr-stale:    365
           days-before-pr-close:    30

changelog.md

@@ -33,25 +33,10 @@ errors.
 
 - Bitshift operators (`shl`, `shr`, `ashr`) now apply bitmasking to the right operand in the C/C++/VM/JS backends.
 
-- Adds a new warning `--warning:ImplicitRangeConversion` that detects downsizing implicit conversions to range types (e.g., `int -> range[0..255]` or `range[1..256] -> range[0..255]`) that could cause runtime panics. Safe conversions like `range[0..255] -> range[0..65535]` and explicit casts do not trigger warnings. `int` to `Natural` and `Positive` conversions do not trigger warnings, which can be enabled with `--warning:systemRangeConversion`.
-
-- Procedure compatibility also checks the backend representation of the
-parameter and result types, not just their source-level shape. Use
-`--legacy:procParamTypeBackendAliases` to restore the older behavior.
-
 ## Standard library additions and changes
 
 [//]: # "Additions:"
 
-- Added `system.readRawDataStable`, a companion to `readRawData` that returns a
-  raw `ptr UncheckedArray[char]` into a string's character data which stays valid
-  across moves and copies of the string value. It is available under every string
-  implementation (refc, ARC/ORC and `--strings:sso`) with the same signature, so
-  code can pin an interior buffer pointer today and be ready for `--strings:sso`
-  without `when declared` guards. Under `--strings:sso` it promotes a small inline
-  string to its heap representation first; under the other implementations the data
-  is already heap-resident, so it is equivalent to `readRawData`.
-
 - `setutils.symmetricDifference` along with its operator version
   `` setutils.`-+-` `` and in-place version `setutils.toggle` have been added
   to more efficiently calculate the symmetric difference of bitsets.
@@ -73,15 +58,6 @@ parameter and result types, not just their source-level shape. Use
     - `copyDirWithPermissions` to recursively preserve attributes
 
 - `system.setLenUninit` now supports refc, JS and VM backends.
-- `system.setLenUninit` for the `string` type. Allows setting length without initializing new memory on growth.
-
-- `std/parseopt` now supports multiple parser modes via a `CliMode` enum.
-  Modes include `Nim` (default, fully compatible) and two new experimental modes:
-  `Lax` and `Gnu` for different option parsing behaviors.
-
-- `std/nre2` is added to replace deprecated NRE.
-
-- `system.typeof` adds a new parameter `modifierMode` to specify how type modifiers are handled.
 
 [//]: # "Changes:"
 
@@ -89,14 +65,6 @@ parameter and result types, not just their source-level shape. Use
 - `min`, `max`, and `sequtils`' `minIndex`, `maxIndex` and `minmax` for `openArray`s now accept a comparison function.
 - `system.substr` implementation now uses `copymem` (wrapped C `memcpy`) for copying data, if available at compilation.
 - `system.newStringUninit` is now considered free of side-effects allowing it to be used with `--experimental:strictFuncs`.
-- `std/re` and `std/nre` are deprecated as PCRE library is obsolete.
-  Use https://github.com/nitely/nim-regex or `std/nre2`.
-  See: https://github.com/nim-lang/Nim/issues/23668.
-- `std/pegs` now correctly lexes UTF-8 bytes inside bare identifier-style
-  terminals, so case-insensitive matching of non-ASCII terms (e.g. ``\i café``)
-  works without single-quoting.
-- `std/uri`: The `?` operator now appends query parameters to an existing query
-  string instead of replacing it. Fixes [#19782](https://github.com/nim-lang/Nim/issues/19782).
 
 ## Language changes
 
@@ -144,9 +112,7 @@ parameter and result types, not just their source-level shape. Use
 
 ## Tool changes
 
-- Added `--raw` flag when generating JSON docs to not render markup.
 - Added `--stdinfile` flag to name of the file used when running program from stdin (defaults to `stdinfile.nim`)
-- Added `--styleCheck:warning` flag to treat style check violations as warnings.
 
 ## Documentation changes
 

compiler/ast.nim

@@ -36,13 +36,6 @@ proc setupProgram*(config: ConfigRef; cache: IdentCache) =
   when not defined(nimKochBootstrap):
     program = createDecodeContext(config, cache)
 
-proc setIcMainModule*(fileIdx: FileIndex) =
-  ## Tells the IC loader which module is being compiled fresh, so that
-  ## re-exports of that module's symbols by dependencies are not loaded as
-  ## duplicate stubs.
-  when not defined(nimKochBootstrap):
-    ast2nif.setMainModule(program, fileIdx)
-
 template loadSym(s: PSym) =
   ## Loads a symbol from NIF file if it's in Partial state.
   when not defined(nimKochBootstrap):
@@ -77,16 +70,6 @@ proc backendEnsureMutable*(t: PType) {.inline.} =
   # ^ IC review this later
   if t.state == Partial: loadType(t)
 
-proc unsealForTransform*(t: PType) {.inline.} =
-  ## The transformer/lambda lifting also run inside `nim m` when the VM
-  ## compiles a LOADED routine (macro evaluation, `getImpl`). Their mutations
-  ## are process-local — transformed bodies are never written back to a NIF —
-  ## so downgrade the loaded type to mutable, mirroring the `cmdNifC` loader
-  ## which loads everything `Complete` for exactly this reason (see
-  ## `ast2nif.loadedState`).
-  if t.state == Partial: loadType(t)
-  if t.state == Sealed: t.state = Complete
-
 proc owner*(s: PSym): PSym {.inline.} =
   if s.state == Partial: loadSym(s)
   result = s.ownerFieldImpl
@@ -238,10 +221,7 @@ proc position*(s: PSym): int {.inline.} =
   result = s.positionImpl
 
 proc `position=`*(s: PSym, val: int) {.inline.} =
-  # No `Sealed` guard: the VM reuses `position` as a register slot while compiling
-  # a macro for execution (see `vmgen.genGenericParams`), which under IC may be a
-  # macro loaded from a NIF file. The macro is run, not code-generated, so this
-  # scratch mutation is harmless.
+  assert s.state != Sealed
   if s.state == Partial: loadSym(s)
   s.positionImpl = val
 
@@ -465,13 +445,9 @@ var gconfig {.threadvar.}: Gconfig
 proc setUseIc*(useIc: bool) = gconfig.useIc = useIc
 
 proc comment*(n: PNode): string =
-  if nfHasComment in n.flags:
-    # NIF-based IC doesn't serialize comments, but the comment table is keyed by
-    # the node's address (`nodeId`), which is unique among live nodes; a loaded
-    # node that carries `nfHasComment` simply has no entry here (its comment was
-    # set in another process), so `getOrDefault` safely returns "" for it while
-    # in-process VM macro nodes (e.g. newCommentStmtNode) still round-trip.
-    result = gconfig.comments.getOrDefault(n.nodeId)
+  if nfHasComment in n.flags and not gconfig.useIc:
+    # IC doesn't track comments, see `packed_ast`, so this could fail
+    result = gconfig.comments[n.nodeId]
   else:
     result = ""
 
@@ -502,6 +478,13 @@ proc getPIdent*(a: PNode): PIdent {.inline.} =
   of nkOpenSymChoice, nkClosedSymChoice, nkOpenSym: a.sons[0].sym.name
   else: nil
 
+const
+  moduleShift = when defined(cpu32): 20 else: 24
+
+template toId*(a: ItemId): int =
+  let x = a
+  (x.module.int shl moduleShift) + x.item.int
+
 template id*(a: PType | PSym): int = toId(a.itemId)
 
 type
@@ -510,29 +493,14 @@ type
     symId*: int32
     typeId*: int32
     sealed*: bool
-    backendMinted*: bool
     disambTable*: CountTable[PIdent]
 
+const
+  PackageModuleId* = -3'i32
+
 proc idGeneratorFromModule*(m: PSym): IdGenerator =
   assert m.kind == skModule
   result = IdGenerator(module: m.itemId.module, symId: m.itemId.item, typeId: 0, disambTable: initCountTable[PIdent]())
-  result.disambTable.inc m.name
-
-proc idGeneratorForBackend*(m: PSym): IdGenerator =
-  ## Like `idGeneratorFromModule`, but for IC codegen (`nim nifc`): symbols and
-  ## types minted fresh during codegen (transf labels/temps, lifted hooks, type
-  ## copies) must not collide with the itemIds the NIF loader synthesizes for
-  ## lazily-loaded symbols/types of the same module — those come from a
-  ## per-module load-order counter that keeps running while codegen mints its
-  ## own ids. A collision corrupts itemId-keyed tables, e.g. `transf`'s inline
-  ## iterator mapping then substitutes a random loaded sym (a call's callee)
-  ## with a `:tmp` block label. Backend-minted ids carry a marker bit in the
-  ## module half (see `itemids.backendItemId`), so the two id spaces are
-  ## disjoint by construction.
-  assert m.kind == skModule
-  result = IdGenerator(module: m.itemId.module, symId: 0, typeId: 0,
-                       backendMinted: true, disambTable: initCountTable[PIdent]())
-  result.disambTable.inc m.name
 
 proc idGeneratorForPackage*(nextIdWillBe: int32): IdGenerator =
   result = IdGenerator(module: PackageModuleId, symId: nextIdWillBe - 1'i32, typeId: 0, disambTable: initCountTable[PIdent]())
@@ -540,14 +508,12 @@ proc idGeneratorForPackage*(nextIdWillBe: int32): IdGenerator =
 proc nextSymId(x: IdGenerator): ItemId {.inline.} =
   assert(not x.sealed)
   inc x.symId
-  result = if x.backendMinted: backendItemId(x.module, x.symId)
-           else: itemId(x.module, x.symId)
+  result = ItemId(module: x.module, item: x.symId)
 
 proc nextTypeId*(x: IdGenerator): ItemId {.inline.} =
   assert(not x.sealed)
   inc x.typeId
-  result = if x.backendMinted: backendItemId(x.module, x.typeId)
-           else: itemId(x.module, x.typeId)
+  result = ItemId(module: x.module, item: x.typeId)
 
 when false:
   proc nextId*(x: IdGenerator): ItemId {.inline.} =
@@ -583,25 +549,22 @@ proc addAllowNil*(father, son: PNode) {.inline.} =
   father.sons.add(son)
 
 proc add*(father, son: PType) =
-  ensureMutable father
   assert father.kind != tyProc or father.sonsImpl.len == 0
   assert son != nil
   father.sonsImpl.add son
 
 proc addAllowNil*(father, son: PType) {.inline.} =
-  ensureMutable father
   assert father.kind != tyProc or father.sonsImpl.len == 0
   father.sonsImpl.add son
 
-proc `[]`*(n: PType, i: int): PType {.inline.} =
+template `[]`*(n: PType, i: int): PType =
   if n.state == Partial: loadType(n)
   if n.kind == tyProc and i > 0:
     assert n.nImpl[i] != nil and n.nImpl[i].sym != nil
     n.nImpl[i].sym.typ
   else:
     n.sonsImpl[i]
-
-proc `[]=`*(n: PType, i: int; x: PType) {.inline.} =
+template `[]=`*(n: PType, i: int; x: PType) =
   if n.state == Partial: loadType(n)
   if n.kind == tyProc and i > 0:
     assert n.nImpl[i] != nil and n.nImpl[i].sym != nil
@@ -609,13 +572,12 @@ proc `[]=`*(n: PType, i: int; x: PType) {.inline.} =
   else:
     n.sonsImpl[i] = x
 
-proc `[]`*(n: PType, i: BackwardsIndex): PType {.inline.} =
+template `[]`*(n: PType, i: BackwardsIndex): PType =
   if n.state == Partial: loadType(n)
-  n[n.sonsImpl.len - i.int]
-
-proc `[]=`*(n: PType, i: BackwardsIndex; x: PType) {.inline.} =
+  n[n.len - i.int]
+template `[]=`*(n: PType, i: BackwardsIndex; x: PType) =
   if n.state == Partial: loadType(n)
-  n[n.sonsImpl.len - i.int] = x
+  n[n.len - i.int] = x
 
 proc getDeclPragma*(n: PNode): PNode =
   ## return the `nkPragma` node for declaration `n`, or `nil` if no pragma was found.
@@ -968,7 +930,6 @@ proc `$`*(s: PSym): string =
     result = "<nil>"
 
 proc len*(n: PType): int {.inline.} =
-  if n.state == Partial: loadType(n)
   if n.kind == tyProc:
     result = if n.nImpl == nil: 0 else: n.nImpl.len
   else:
@@ -1076,11 +1037,6 @@ proc newType*(kind: TTypeKind; idgen: IdGenerator; owner: PSym; son: sink PType
     if result.itemId.module == 55 and result.itemId.item == 2:
       echo "KNID ", kind
       writeStackTrace()
-  when defined(icDbg):
-    if kind == tyOpenArray:
-      echo "NEWTYPE openArray id=", id.module, ".", id.item,
-        " owner=", (if owner != nil: owner.name.s else: "nil")
-      echo getStackTrace()
 
 proc setSons*(dest: PType; sons: sink seq[PType]) {.inline.} =
   assert dest.kind != tyProc or sons.len <= 1
@@ -1143,19 +1099,10 @@ proc copyType*(t: PType, idgen: IdGenerator, owner: PSym): PType =
   assignType(result, t)
   result.symImpl = t.sym          # backend-info should not be copied
 
-proc exactReplica*(t: PType; idgen: IdGenerator): PType =
-  ## Replica that KEEPS `itemId` — the generic-param binding tables
-  ## (`LayeredIdTable`) key on it, so the copy must keep matching its
-  ## original — but mints a FRESH `uniqueId`: uniqueId is the SERIALIZATION
-  ## identity (NIF type names key on it) and must be unique per instance.
-  ## Replicas sharing the original's uniqueId serialized as duplicate defs
-  ## under one NIF name; the loader collapsed them into a single type,
-  ## losing their flag differences (use-site `tfUnresolved` typedescs) or
-  ## their structure (meta instance bodies shadowing a generic's canonical
-  ## body).
+proc exactReplica*(t: PType): PType =
   result = PType(kind: t.kind, ownerFieldImpl: t.owner, sizeImpl: defaultSize,
                  alignImpl: defaultAlignment, itemId: t.itemId,
-                 uniqueId: nextTypeId(idgen))
+                 uniqueId: t.uniqueId)
   assignType(result, t)
   result.symImpl = t.sym          # backend-info should not be copied
 
@@ -1221,7 +1168,6 @@ proc skipTypesOrNil*(t: PType, kinds: TTypeKinds): PType =
   ## same as skipTypes but handles 'nil'
   result = t
   while result != nil and result.kind in kinds:
-    if result.state == Partial: loadType(result)
     if result.sonsImpl.len == 0: return nil
     result = last(result)
 
@@ -1243,12 +1189,7 @@ proc propagateToOwner*(owner, elem: PType; propagateHasAsgn = true) =
     let o2 = owner.skipTypes({tyGenericInst, tyAlias, tySink})
     if o2.kind in {tyTuple, tyObject, tyArray,
                    tySequence, tyString, tySet, tyDistinct}:
-      if o2.state == Sealed:
-        # During the original compilation, propagateToOwner set tfHasAsgn/tfHasOwned on the type before it was sealed
-        # On IC reload, the sealed type already has those flags
-        assert mask <= o2.flags, "IC bug: sealed type missing propagated flags"
-      else:
-        o2.incl mask
+      o2.incl mask
       owner.incl mask
 
   if owner.kind notin {tyProc, tyGenericInst, tyGenericBody,
@@ -1318,15 +1259,11 @@ proc transitionNoneToSym*(n: PNode) =
   transitionNodeKindCommon(nkSym)
 
 template transitionSymKindCommon*(k: TSymKind) =
-  # Under IC the symbol may still be an unloaded stub (`skStub`); materialise it
-  # first so its kind-specific fields (read below as `obj.*`) actually exist.
-  if s.state == Partial: loadSym(s)
   let obj {.inject.} = s[]
   s[] = TSym(kindImpl: k, itemId: obj.itemId, magicImpl: obj.magicImpl, typImpl: obj.typImpl, name: obj.name,
              infoImpl: obj.infoImpl, ownerFieldImpl: obj.ownerFieldImpl, flagsImpl: obj.flagsImpl, astImpl: obj.astImpl,
              optionsImpl: obj.optionsImpl, positionImpl: obj.positionImpl, offsetImpl: obj.offsetImpl,
-             disamb: obj.disamb, locImpl: obj.locImpl, annexImpl: obj.annexImpl, constraintImpl: obj.constraintImpl,
-             instantiatedFromImpl: obj.instantiatedFromImpl)
+             locImpl: obj.locImpl, annexImpl: obj.annexImpl, constraintImpl: obj.constraintImpl)
   when hasFFI:
     s.cnameImpl = obj.cnameImpl
   when defined(nimsuggest):
@@ -1697,13 +1634,9 @@ proc canRaise*(fn: PNode): bool =
     if fn.typ.n[0].kind == nkSym:
       result = false
     else:
-      # A proc-typed value with no explicit raises slot still has
-      # unspecified effects, which sempass2 treats conservatively.
-      # Codegen needs to do the same in order to keep goto-exception
-      # checks after indirect/closure calls.
       result = ((fn.typ.n[0].len < effectListLen) or
-        fn.typ.n[0][exceptionEffects] == nil or
-        fn.typ.n[0][exceptionEffects].safeLen > 0)
+        (fn.typ.n[0][exceptionEffects] != nil and
+        fn.typ.n[0][exceptionEffects].safeLen > 0))
   else:
     result = false
 

compiler/astdef.nim

@@ -20,9 +20,6 @@ export int128
 import nodekinds
 export nodekinds
 
-import itemids
-export itemids
-
 type
   TCallingConvention* = enum
     ccNimCall = "nimcall"           # nimcall, also the default
@@ -205,11 +202,7 @@ type
     tySequence,
     tyProc,
     tyPointer, tyOpenArray,
-    tyString, tyCstring,
-    tyForward,
-      # a type not yet semchecked
-      # When semcheck a type section, all types defined in it are initialized to tyForward
-
+    tyString, tyCstring, tyForward,
     tyInt, tyInt8, tyInt16, tyInt32, tyInt64, # signed integers
     tyFloat, tyFloat32, tyFloat64, tyFloat128,
     tyUInt, tyUInt8, tyUInt16, tyUInt32, tyUInt64,
@@ -574,6 +567,23 @@ const
   generatedMagics* = {mNone, mIsolate, mFinished, mOpenArrayToSeq}
     ## magics that are generated as normal procs in the backend
 
+type
+  ItemId* = object
+    module*: int32
+    item*: int32
+
+proc `$`*(x: ItemId): string =
+  "(module: " & $x.module & ", item: " & $x.item & ")"
+
+proc `==`*(a, b: ItemId): bool {.inline.} =
+  a.item == b.item and a.module == b.module
+
+proc hash*(x: ItemId): Hash =
+  var h: Hash = hash(x.module)
+  h = h !& hash(x.item)
+  result = !$h
+
+
 type
   PNode* = ref TNode
   TNodeSeq* = seq[PNode]
@@ -687,7 +697,6 @@ type
 
   PLib* = ref TLib
   TSym* {.acyclic.} = object # Keep in sync with ast2nif.nim
-                             # Check `transitionSymKindCommon` in ast.nim when add a new field.
     itemId*: ItemId
     # proc and type instantiations are cached in the generic symbol
     state*: ItemState
@@ -986,8 +995,7 @@ proc newStrNode*(strVal: string; info: TLineInfo): PNode =
 
 type
   LogEntryKind* = enum
-    HookEntry, ConverterEntry, MethodEntry, EnumToStrEntry, GenericInstEntry,
-    PureEnumEntry
+    HookEntry, ConverterEntry, MethodEntry, EnumToStrEntry, GenericInstEntry
   LogEntry* = object
     kind*: LogEntryKind
     op*: TTypeAttachedOp

compiler/astyaml.nim

@@ -43,13 +43,13 @@ proc flagsToStr[T](flags: set[T]): string =
 proc lineInfoToStr*(conf: ConfigRef; info: TLineInfo): string =
   result = "["
   result.addYamlString(toFilename(conf, info))
-  result.addf ", $1, $2]", toLinenumber(info), toColumn(info)
+  result.addf ", $1, $2]", [toLinenumber(info), toColumn(info)]
 
-proc treeToYamlAux(res: var string; conf: ConfigRef; n: PNode; marker: var IntSet; nl: bool, indent, maxRecDepth: int)
-proc symToYamlAux(res: var string; conf: ConfigRef; n: PSym; marker: var IntSet; nl: bool, indent, maxRecDepth: int)
-proc typeToYamlAux(res: var string; conf: ConfigRef; n: PType; marker: var IntSet; nl: bool, indent, maxRecDepth: int)
+proc treeToYamlAux(res: var string; conf: ConfigRef; n: PNode; marker: var IntSet; indent, maxRecDepth: int)
+proc symToYamlAux(res: var string; conf: ConfigRef; n: PSym; marker: var IntSet; indent, maxRecDepth: int)
+proc typeToYamlAux(res: var string; conf: ConfigRef; n: PType; marker: var IntSet; indent, maxRecDepth: int)
 
-proc symToYamlAux(res: var string; conf: ConfigRef; n: PSym; marker: var IntSet; nl: bool, indent: int; maxRecDepth: int) =
+proc symToYamlAux(res: var string; conf: ConfigRef; n: PSym; marker: var IntSet; indent: int; maxRecDepth: int) =
   if n == nil:
     res.add("null")
   elif containsOrIncl(marker, n.id):
@@ -57,12 +57,10 @@ proc symToYamlAux(res: var string; conf: ConfigRef; n: PSym; marker: var IntSet;
   else:
     let istr = spaces(indent * 4)
 
-    if nl:
-      res.addf("\n$1", istr)
     res.addf("kind: $1", [makeYamlString($n.kind)])
     res.addf("\n$1name: $2", [istr, makeYamlString(n.name.s)])
     res.addf("\n$1typ: ", [istr])
-    res.typeToYamlAux(conf, n.typ, marker, true, indent + 1, maxRecDepth - 1)
+    res.typeToYamlAux(conf, n.typ, marker, indent + 1, maxRecDepth - 1)
     if conf != nil:
       # if we don't pass the config, we probably don't care about the line info
       res.addf("\n$1info: $2", [istr, lineInfoToStr(conf, n.info)])
@@ -70,7 +68,7 @@ proc symToYamlAux(res: var string; conf: ConfigRef; n: PSym; marker: var IntSet;
       res.addf("\n$1flags: $2", [istr, flagsToStr(n.flags)])
     res.addf("\n$1magic: $2", [istr, makeYamlString($n.magic)])
     res.addf("\n$1ast: ", [istr])
-    res.treeToYamlAux(conf, n.ast, marker, true, indent + 1, maxRecDepth - 1)
+    res.treeToYamlAux(conf, n.ast, marker, indent + 1, maxRecDepth - 1)
     res.addf("\n$1options: $2", [istr, flagsToStr(n.options)])
     res.addf("\n$1position: $2", [istr, $n.position])
     res.addf("\n$1k: $2", [istr, makeYamlString($n.loc.k)])
@@ -78,57 +76,53 @@ proc symToYamlAux(res: var string; conf: ConfigRef; n: PSym; marker: var IntSet;
     if card(n.loc.flags) > 0:
       res.addf("\n$1flags: $2", [istr, makeYamlString($n.loc.flags)])
     res.addf("\n$1snippet: $2", [istr, n.loc.snippet])
-    res.addf("\n$1lode: ", [istr])
-    res.treeToYamlAux(conf, n.loc.lode, marker, true, indent + 1, maxRecDepth - 1)
+    res.addf("\n$1lode: $2", [istr])
+    res.treeToYamlAux(conf, n.loc.lode, marker, indent + 1, maxRecDepth - 1)
 
-proc typeToYamlAux(res: var string; conf: ConfigRef; n: PType; marker: var IntSet; nl: bool, indent: int; maxRecDepth: int) =
+proc typeToYamlAux(res: var string; conf: ConfigRef; n: PType; marker: var IntSet; indent: int; maxRecDepth: int) =
   if n == nil:
     res.add("null")
   elif containsOrIncl(marker, n.id):
     res.addf "\"$1 @$2\"" % [$n.kind, strutils.toHex(cast[uint](n), sizeof(n) * 2)]
   else:
     let istr = spaces(indent * 4)
-    if nl:
-      res.addf("\n$1", istr)
     res.addf("kind: $2", [istr, makeYamlString($n.kind)])
-    res.addf("\n$1sym: ", istr)
-    res.symToYamlAux(conf, n.sym, marker, true, indent + 1, maxRecDepth - 1)
-    res.addf("\n$1n: ", istr)
-    res.treeToYamlAux(conf, n.n, marker, true, indent + 1, maxRecDepth - 1)
+    res.addf("\n$1sym: ")
+    res.symToYamlAux(conf, n.sym, marker, indent + 1, maxRecDepth - 1)
+    res.addf("\n$1n: ")
+    res.treeToYamlAux(conf, n.n, marker, indent + 1, maxRecDepth - 1)
     if card(n.flags) > 0:
       res.addf("\n$1flags: $2", [istr, flagsToStr(n.flags)])
     res.addf("\n$1callconv: $2", [istr, makeYamlString($n.callConv)])
     res.addf("\n$1size: $2", [istr, $(n.size)])
     res.addf("\n$1align: $2", [istr, $(n.align)])
     if n.hasElementType:
-      res.addf("\n$1sons:", istr)
+      res.addf("\n$1sons:")
       for a in n.kids:
-        res.addf("\n$1  - ", istr)
-        res.typeToYamlAux(conf, a, marker, false, indent + 1, maxRecDepth - 1)
+        res.addf("\n  - ")
+        res.typeToYamlAux(conf, a, marker, indent + 1, maxRecDepth - 1)
 
-proc treeToYamlAux(res: var string; conf: ConfigRef; n: PNode; marker: var IntSet; nl: bool, indent: int;
+proc treeToYamlAux(res: var string; conf: ConfigRef; n: PNode; marker: var IntSet; indent: int;
                    maxRecDepth: int) =
   if n == nil:
     res.add("null")
   else:
     var istr = spaces(indent * 4)
-    if nl:
-      res.addf("\n$1", istr)
     res.addf("kind: $1" % [makeYamlString($n.kind)])
 
     if maxRecDepth != 0:
       if conf != nil:
         res.addf("\n$1info: $2", [istr, lineInfoToStr(conf, n.info)])
       case n.kind
-      of nkCharLit .. nkUInt64Lit:
+      of nkCharLit .. nkInt64Lit:
         res.addf("\n$1intVal: $2", [istr, $(n.intVal)])
-      of nkFloatLit .. nkFloat128Lit:
+      of nkFloatLit, nkFloat32Lit, nkFloat64Lit:
         res.addf("\n$1floatVal: $2", [istr, n.floatVal.toStrMaxPrecision])
       of nkStrLit .. nkTripleStrLit:
         res.addf("\n$1strVal: $2", [istr, makeYamlString(n.strVal)])
       of nkSym:
         res.addf("\n$1sym: ", [istr])
-        res.symToYamlAux(conf, n.sym, marker, true, indent + 1, maxRecDepth)
+        res.symToYamlAux(conf, n.sym, marker, indent + 1, maxRecDepth)
       of nkIdent:
         if n.ident != nil:
           res.addf("\n$1ident: $2", [istr, makeYamlString(n.ident.s)])
@@ -139,22 +133,22 @@ proc treeToYamlAux(res: var string; conf: ConfigRef; n: PNode; marker: var IntSe
           res.addf("\n$1sons: ", [istr])
           for i in 0 ..< n.len:
             res.addf("\n$1  - ", [istr])
-            res.treeToYamlAux(conf, n[i], marker, false, indent + 1, maxRecDepth - 1)
+            res.treeToYamlAux(conf, n[i], marker, indent + 1, maxRecDepth - 1)
       if n.typ != nil:
         res.addf("\n$1typ: ", [istr])
-        res.typeToYamlAux(conf, n.typ, marker, true, indent + 1, maxRecDepth)
+        res.typeToYamlAux(conf, n.typ, marker, indent + 1, maxRecDepth)
 
 proc treeToYaml*(conf: ConfigRef; n: PNode; indent: int = 0; maxRecDepth: int = -1): string =
   var marker = initIntSet()
   result = newStringOfCap(1024)
-  result.treeToYamlAux(conf, n, marker, false, indent, maxRecDepth)
+  result.treeToYamlAux(conf, n, marker, indent, maxRecDepth)
 
 proc typeToYaml*(conf: ConfigRef; n: PType; indent: int = 0; maxRecDepth: int = -1): string =
   var marker = initIntSet()
   result = newStringOfCap(1024)
-  result.typeToYamlAux(conf, n, marker, false, indent, maxRecDepth)
+  result.typeToYamlAux(conf, n, marker, indent, maxRecDepth)
 
 proc symToYaml*(conf: ConfigRef; n: PSym; indent: int = 0; maxRecDepth: int = -1): string =
   var marker = initIntSet()
   result = newStringOfCap(1024)
-  result.symToYamlAux(conf, n, marker, false, indent, maxRecDepth)
+  result.symToYamlAux(conf, n, marker, indent, maxRecDepth)

compiler/btrees.nim

@@ -69,7 +69,7 @@ proc copyHalf[Key, Val](h, result: Node[Key, Val]) =
       result.links[j] = h.links[Mhalf + j]
   else:
     for j in 0..<Mhalf:
-      when defined(gcArc) or defined(gcOrc) or defined(gcAtomicArc) or defined(gcYrc):
+      when defined(gcArc) or defined(gcOrc) or defined(gcAtomicArc):
         result.vals[j] = move h.vals[Mhalf + j]
       else:
         shallowCopy(result.vals[j], h.vals[Mhalf + j])
@@ -92,7 +92,7 @@ proc insert[Key, Val](h: Node[Key, Val], key: Key, val: Val): Node[Key, Val] =
       if less(key, h.keys[j]): break
       inc j
     for i in countdown(h.entries, j+1):
-      when defined(gcArc) or defined(gcOrc) or defined(gcAtomicArc) or defined(gcYrc):
+      when defined(gcArc) or defined(gcOrc) or defined(gcAtomicArc):
         h.vals[i] = move h.vals[i-1]
       else:
         shallowCopy(h.vals[i], h.vals[i-1])

compiler/ccgcalls.nim

@@ -230,29 +230,20 @@ proc genOpenArraySlice(p: BProc; q: PNode; formalType, destType: PType; prepareF
   of tyString, tySequence:
     let atyp = skipTypes(a.t, abstractInst)
     if formalType.skipTypes(abstractInst).kind in {tyVar} and atyp.kind == tyString and
-        optSeqDestructors in p.config.globalOptions and not p.config.usesSso():
+        optSeqDestructors in p.config.globalOptions:
       let bra = byRefLoc(p, a)
       p.s(cpsStmts).addCallStmt(cgsymValue(p.module, "nimPrepareStrMutationV2"),
         bra)
-    if p.config.usesSso() and
-        skipTypes(a.t, abstractVar + abstractInst).kind == tyString:
-      let strPtr = if atyp.kind in {tyVar} and not compileToCpp(p.module): ra
-                   else: addrLoc(p.config, a)
-      result = (
-        cCast(ptrType(dest), cOp(Add, NimInt,
-          cCall(cgsymValue(p.module, "nimStrData"), strPtr), rb)),
-        lengthExpr)
+    var val: Snippet
+    if atyp.kind in {tyVar} and not compileToCpp(p.module):
+      val = cDeref(ra)
     else:
-      var val: Snippet
-      if atyp.kind in {tyVar} and not compileToCpp(p.module):
-        val = cDeref(ra)
-      else:
-        val = ra
-      result = (
-        cIfExpr(dataFieldAccessor(p, val),
-          cCast(ptrType(dest), cOp(Add, NimInt, dataField(p, val), rb)),
-          NimNil),
-        lengthExpr)
+      val = ra
+    result = (
+      cIfExpr(dataFieldAccessor(p, val),
+        cCast(ptrType(dest), cOp(Add, NimInt, dataField(p, val), rb)),
+        NimNil),
+      lengthExpr)
   else:
     result = ("", "")
     internalError(p.config, "openArrayLoc: " & typeToString(a.t))
@@ -296,22 +287,11 @@ proc openArrayLoc(p: BProc, formalType: PType, n: PNode; result: var Builder) =
     of tyString, tySequence:
       let ntyp = skipTypes(n.typ, abstractInst)
       if formalType.skipTypes(abstractInst).kind in {tyVar} and ntyp.kind == tyString and
-          optSeqDestructors in p.config.globalOptions and not p.config.usesSso():
+          optSeqDestructors in p.config.globalOptions:
         let bra = byRefLoc(p, a)
         p.s(cpsStmts).addCallStmt(cgsymValue(p.module, "nimPrepareStrMutationV2"),
           bra)
-      if p.config.usesSso() and
-          skipTypes(n.typ, abstractVar + abstractInst).kind == tyString:
-        if ntyp.kind in {tyVar} and not compileToCpp(p.module):
-          let ra = a.rdLoc
-          result.add(cCall(cgsymValue(p.module, "nimStrData"), ra))
-          result.addArgumentSeparator()
-          result.add(cCall(cgsymValue(p.module, "nimStrLen"), cDeref(ra)))
-        else:
-          result.add(cCall(cgsymValue(p.module, "nimStrData"), addrLoc(p.config, a)))
-          result.addArgumentSeparator()
-          result.add(lenExpr(p, a))
-      elif ntyp.kind in {tyVar} and not compileToCpp(p.module):
+      if ntyp.kind in {tyVar} and not compileToCpp(p.module):
         let ra = a.rdLoc
         var t = TLoc(snippet: cDeref(ra))
         let lt = lenExpr(p, t)
@@ -335,14 +315,9 @@ proc openArrayLoc(p: BProc, formalType: PType, n: PNode; result: var Builder) =
         let ra = a.rdLoc
         var t = TLoc(snippet: cDeref(ra))
         let lt = lenExpr(p, t)
-        if p.config.usesSso():
-          result.add(cCall(cgsymValue(p.module, "nimStrData"), ra))
-          result.addArgumentSeparator()
-          result.add(cCall(cgsymValue(p.module, "nimStrLen"), t.snippet))
-        else:
-          result.add(cIfExpr(dataFieldAccessor(p, t.snippet), dataField(p, t.snippet), NimNil))
-          result.addArgumentSeparator()
-          result.add(lt)
+        result.add(cIfExpr(dataFieldAccessor(p, t.snippet), dataField(p, t.snippet), NimNil))
+        result.addArgumentSeparator()
+        result.add(lt)
       of tyArray:
         let ra = rdLoc(a)
         result.add(ra)
@@ -356,7 +331,7 @@ proc withTmpIfNeeded(p: BProc, a: TLoc, needsTmp: bool): TLoc =
   # Bug https://github.com/status-im/nimbus-eth2/issues/1549
   # Aliasing is preferred over stack overflows.
   # Also don't regress for non ARC-builds, too risky.
-  if needsTmp and a.lode.typ != nil and p.config.selectedGC in {gcArc, gcAtomicArc, gcOrc, gcYrc} and
+  if needsTmp and a.lode.typ != nil and p.config.selectedGC in {gcArc, gcAtomicArc, gcOrc} and
       getSize(p.config, a.lode.typ) < 1024:
     result = getTemp(p, a.lode.typ, needsInit=false)
     genAssignment(p, result, a, {})
@@ -369,8 +344,7 @@ proc expressionsNeedsTmp(p: BProc, a: TLoc): TLoc =
 
 proc genArgStringToCString(p: BProc, n: PNode; result: var Builder; needsTmp: bool) {.inline.} =
   var a = initLocExpr(p, n[0])
-  let tmp = withTmpIfNeeded(p, a, needsTmp)
-  let ra = if p.config.usesSso(): byRefLoc(p, tmp) else: tmp.rdLoc
+  let ra = withTmpIfNeeded(p, a, needsTmp).rdLoc
   result.addCall(cgsymValue(p.module, "nimToCStringConv"), ra)
 
 proc genArg(p: BProc, n: PNode, param: PSym; call: PNode; result: var Builder; needsTmp = false) =
@@ -394,7 +368,7 @@ proc genArg(p: BProc, n: PNode, param: PSym; call: PNode; result: var Builder; n
     # variable. Thus, we create a temporary pointer variable instead.
     let needsIndirect = mapType(p.config, n[0].typ, mapTypeChooser(n[0]) == skParam) != ctArray
     if needsIndirect:
-      n.typ = n.typ.exactReplica(p.module.idgen)
+      n.typ = n.typ.exactReplica
       n.typ.incl tfVarIsPtr
     a = initLocExprSingleUse(p, n)
     a = withTmpIfNeeded(p, a, needsTmp)
@@ -909,16 +883,6 @@ proc isInactiveDestructorCall(p: BProc, e: PNode): bool =
 proc genAsgnCall(p: BProc, le, ri: PNode, d: var TLoc) =
   if p.withinBlockLeaveActions > 0 and isInactiveDestructorCall(p, ri):
     return
-  when defined(icDbgHash):
-    if ri[0].typ == nil:
-      echo "NILCALLEE kind=", ri[0].kind,
-        " sym=", (if ri[0].kind == nkSym: ri[0].sym.name.s else: "-"),
-        " symKind=", (if ri[0].kind == nkSym: $ri[0].sym.kind else: "-"),
-        " flags=", (if ri[0].kind == nkSym: $ri[0].sym.flags else: "-"),
-        " lazy=", nfLazyType in ri[0].flags,
-        " inProc=", (if p.prc != nil: p.prc.name.s else: "NIL"),
-        " module=", p.module.module.name.s
-      raiseAssert "nil callee type, see NILCALLEE above"
   if ri[0].typ.skipTypes({tyGenericInst, tyAlias, tySink, tyOwned}).callConv == ccClosure:
     genClosureCall(p, le, ri, d)
   elif ri[0].kind == nkSym and sfInfixCall in ri[0].sym.flags:

compiler/ccgexprs.nim

@@ -216,8 +216,6 @@ proc genOptAsgnTuple(p: BProc, dest, src: TLoc, flags: TAssignmentFlags) =
       flags
   let t = skipTypes(dest.t, abstractInst).getUniqueType()
   for i, t in t.ikids:
-    # Do not produce code for void types
-    if isEmptyType(t): continue
     let field = "Field$1" % [i.rope]
     genAssignment(p, optAsgnLoc(dest, t, field),
                      optAsgnLoc(src, t, field), newflags)
@@ -320,16 +318,12 @@ proc genOpenArrayConv(p: BProc; d: TLoc; a: TLoc; flags: TAssignmentFlags) =
       p.s(cpsStmts).addCallStmt(
         cgsymValue(p.module, "nimPrepareStrMutationV2"),
         bra)
+
     let rd = d.rdLoc
+    let ra = a.rdLoc
+    p.s(cpsStmts).addFieldAssignment(rd, "Field0",
+      cIfExpr(dataFieldAccessor(p, ra), dataField(p, ra), NimNil))
     let la = lenExpr(p, a)
-    if p.config.usesSso():
-      let bra = byRefLoc(p, a)
-      p.s(cpsStmts).addFieldAssignment(rd, "Field0",
-        cCall(cgsymValue(p.module, "nimStrData"), bra))
-    else:
-      let ra = a.rdLoc
-      p.s(cpsStmts).addFieldAssignment(rd, "Field0",
-        cIfExpr(dataFieldAccessor(p, ra), dataField(p, ra), NimNil))
     p.s(cpsStmts).addFieldAssignment(rd, "Field1", la)
   else:
     internalError(p.config, a.lode.info, "cannot handle " & $a.t.kind)
@@ -422,7 +416,7 @@ proc genAssignment(p: BProc, dest, src: TLoc, flags: TAssignmentFlags) =
     else:
       simpleAsgn(p.s(cpsStmts), dest, src)
   of tyArray:
-    if containsGarbageCollectedRef(dest.t) and p.config.selectedGC notin {gcArc, gcAtomicArc, gcOrc, gcYrc, gcHooks}:
+    if containsGarbageCollectedRef(dest.t) and p.config.selectedGC notin {gcArc, gcAtomicArc, gcOrc, gcHooks}:
       genGenericAsgn(p, dest, src, flags)
     else:
       let rd = rdLoc(dest)
@@ -926,8 +920,8 @@ proc genDeref(p: BProc, e: PNode, d: var TLoc) =
     else:
       a = initLocExprSingleUse(p, e[0])
 
-    # bug #23453 #25265
-    if e.typ != nil and e.typ.skipTypes(abstractInst).kind == tyObject:
+    if e.typ != nil and e.typ.kind == tyObject:
+      # bug #23453 #25265
       discard getTypeDesc(p.module, e.typ)
     if d.k == locNone:
       # dest = *a;  <-- We do not know that 'dest' is on the heap!
@@ -962,8 +956,7 @@ proc genDeref(p: BProc, e: PNode, d: var TLoc) =
       putIntoDest(p, d, e, cDeref(rdLoc(a)), a.storage)
 
 proc cowBracket(p: BProc; n: PNode) =
-  if n.kind == nkBracketExpr and optSeqDestructors in p.config.globalOptions and
-      not p.config.usesSso():
+  if n.kind == nkBracketExpr and optSeqDestructors in p.config.globalOptions:
     let strCandidate = n[0]
     if strCandidate.typ.skipTypes(abstractInst).kind == tyString:
       var a: TLoc = initLocExpr(p, strCandidate)
@@ -989,9 +982,7 @@ proc genAddr(p: BProc, e: PNode, d: var TLoc) =
     # bug #19497
     d.lode = e
   else:
-    let ssoStrSub = p.config.usesSso() and e[0].kind == nkBracketExpr and
-        e[0][0].typ.skipTypes(abstractVar).kind == tyString
-    var a: TLoc = initLocExpr(p, e[0], if ssoStrSub: {lfEnforceDeref, lfPrepareForMutation} else: {})
+    var a: TLoc = initLocExpr(p, e[0])
     if e[0].kind in {nkHiddenStdConv, nkHiddenSubConv, nkConv} and not ignoreConv(e[0]):
       # addr (conv x) introduces a temp because `conv x` is not a rvalue
       # transform addr ( conv ( x ) ) -> conv ( addr ( x ) )
@@ -1318,24 +1309,13 @@ proc genSeqElem(p: BProc, n, x, y: PNode, d: var TLoc) =
   if skipTypes(a.t, abstractVar).kind in {tyRef, tyPtr}:
     a.snippet = cDeref(a.snippet)
 
-  if p.config.usesSso() and ty.kind == tyString:
+  if lfPrepareForMutation in d.flags and ty.kind == tyString and
+      optSeqDestructors in p.config.globalOptions:
     let bra = byRefLoc(p, a)
-    if lfPrepareForMutation in d.flags:
-      # Use nimStrAtMutV3 to get a mutable reference (char*) to the element.
-      # Only when mutation is requested: avoids calling nimPrepareStrMutationV2
-      # on const string literals (which would SIGSEGV on write to read-only memory).
-      putIntoDest(p, d, n,
-        cDeref(cCall(cgsymValue(p.module, "nimStrAtMutV3"), bra, rcb)), a.storage)
-    else:
-      putIntoDest(p, d, n,
-        cCall(cgsymValue(p.module, "nimStrAtV3"), bra, rcb), a.storage)
-  else:
-    if lfPrepareForMutation in d.flags and ty.kind == tyString and
-        optSeqDestructors in p.config.globalOptions:
-      let bra = byRefLoc(p, a)
-      p.s(cpsStmts).addCallStmt(cgsymValue(p.module, "nimPrepareStrMutationV2"), bra)
-    let ra = rdLoc(a)
-    putIntoDest(p, d, n, subscript(dataField(p, ra), rcb), a.storage)
+    p.s(cpsStmts).addCallStmt(cgsymValue(p.module, "nimPrepareStrMutationV2"),
+      bra)
+  let ra = rdLoc(a)
+  putIntoDest(p, d, n, subscript(dataField(p, ra), rcb), a.storage)
 
 proc genBracketExpr(p: BProc; n: PNode; d: var TLoc) =
   var ty = skipTypes(n[0].typ, abstractVarRange + tyUserTypeClasses)
@@ -1607,51 +1587,6 @@ proc genSeqElemAppend(p: BProc, e: PNode, d: var TLoc) =
   genAssignment(p, dest, b, {needToCopy})
   gcUsage(p.config, e)
 
-proc genSeqElemAppendV2(p: BProc, e: PNode, d: var TLoc) =
-  # s.add(x) with optSeqDestructors (arc/orc), inlined for direct slot construction:
-  #   NI oldLen = s.len;
-  #   if (s.p == NIM_NIL || (s.p->cap & ~NIM_STRLIT_FLAG) < oldLen + 1)
-  #     s.p = (PayloadType*)prepareSeqAddUninit(oldLen, s.p, 1, sizeof(T), alignof(T));
-  #   s.len = oldLen + 1;
-  #   s.p->data[oldLen] = x;  // direct assignment, no function call overhead
-  let seqtype = skipTypes(e[1].typ, abstractVarRange)
-  var a = initLocExpr(p, e[1])
-  let pt = getSeqPayloadType(p.module, seqtype)
-  let pe = seqPayloadElem(p.module, seqtype)
-  # Capture a stable pointer to the seq BEFORE evaluating the element (e[2]).
-  # Evaluating e[2] may emit move semantics (eqwasMoved) that nil a variable
-  # through which e[1]'s snippet is accessed (e.g. a closure env pointer).
-  inc(p.labels)
-  let seqPtrName = "T" & rope(p.labels) & "_"
-  p.s(cpsLocals).addVar(kind = Local, name = seqPtrName,
-                        typ = ptrType(getTypeDesc(p.module, seqtype)))
-  p.s(cpsStmts).addAssignment(seqPtrName, cAddr(rdLoc(a)))
-  var b = initLocExpr(p, e[2])
-  # All seq operations now go through the stable seqPtrName pointer.
-  let ra = wrapPar(cDeref(seqPtrName))
-  var tmpL = getIntTemp(p)
-  p.s(cpsStmts).addAssignment(tmpL.snippet, dotField(ra, "len"))
-  let pField = dotField(ra, "p")
-  p.s(cpsStmts).addSingleIfStmt(
-      cOp(Or,
-        cOp(Equal, pField, NimNil),
-        cOp(LessThan,
-          cOp(BitAnd, NimInt, derefField(pField, "cap"), cOp(BitNot, NimInt, NimStrlitFlag)),
-          cOp(Add, NimInt, tmpL.snippet, cIntValue(1))))):
-    p.s(cpsStmts).addFieldAssignmentWithValue(ra, "p"):
-      p.s(cpsStmts).addCast(ptrType(pt)):
-        p.s(cpsStmts).addCall(cgsymValue(p.module, "prepareSeqAddUninit"),
-          tmpL.snippet,
-          pField,
-          cIntValue(1),
-          cSizeof(pe),
-          cAlignof(pe))
-  p.s(cpsStmts).addFieldAssignment(ra, "len",
-    cOp(Add, NimInt, tmpL.snippet, cIntValue(1)))
-  var dest = initLoc(locExpr, e[2], OnHeap)
-  dest.snippet = subscript(dataField(p, ra), tmpL.snippet)
-  genAssignment(p, dest, b, {})
-
 proc genDefault(p: BProc; n: PNode; d: var TLoc) =
   if d.k == locNone: d = getTemp(p, n.typ, needsInit=true)
   else: resetLoc(p, d)
@@ -1787,15 +1722,15 @@ proc genNewSeq(p: BProc, e: PNode) =
     let seqtype = skipTypes(e[1].typ, abstractVarRange)
     let ra = a.rdLoc
     let rb = b.rdLoc
+    let et = getTypeDesc(p.module, seqtype.elementType)
     let pt = getSeqPayloadType(p.module, seqtype)
-    let pe = seqPayloadElem(p.module, seqtype)
     p.s(cpsStmts).addFieldAssignment(ra, "len", rb)
     p.s(cpsStmts).addFieldAssignmentWithValue(ra, "p"):
       p.s(cpsStmts).addCast(ptrType(pt)):
         p.s(cpsStmts).addCall(cgsymValue(p.module, "newSeqPayload"),
           rb,
-          cSizeof(pe),
-          cAlignof(pe))
+          cSizeof(et),
+          cAlignof(et))
   else:
     let lenIsZero = e[2].kind == nkIntLit and e[2].intVal == 0
     genNewSeqAux(p, a, b.rdLoc, lenIsZero)
@@ -1808,15 +1743,15 @@ proc genNewSeqOfCap(p: BProc; e: PNode; d: var TLoc) =
     if d.k == locNone: d = getTemp(p, e.typ, needsInit=false)
     let rd = d.rdLoc
     let ra = a.rdLoc
+    let et = getTypeDesc(p.module, seqtype.elementType)
     let pt = getSeqPayloadType(p.module, seqtype)
-    let pe = seqPayloadElem(p.module, seqtype)
     p.s(cpsStmts).addFieldAssignment(rd, "len", cIntValue(0))
     p.s(cpsStmts).addFieldAssignmentWithValue(rd, "p"):
       p.s(cpsStmts).addCast(ptrType(pt)):
         p.s(cpsStmts).addCall(cgsymValue(p.module, "newSeqPayloadUninit"),
           ra,
-          cSizeof(pe),
-          cAlignof(pe))
+          cSizeof(et),
+          cAlignof(et))
   else:
     if d.k == locNone: d = getTemp(p, e.typ, needsInit=false) # bug #22560
     let ra = a.rdLoc
@@ -1889,24 +1824,15 @@ proc genObjConstr(p: BProc, e: PNode, d: var TLoc) =
   var t = e.typ.skipTypes(abstractInstOwned)
   let isRef = t.kind == tyRef
 
-  # check if we need to construct the object in a temporary.
-  # A temp is needed when:
-  # - the constructor produces a ref (isRef)
-  # - the destination is not a writable location (d.k == locNone)
-  # - the constructed type differs from the destination type (subtype
-  #   assignments need the genAssignment path for ObjectAssignmentDefect)
-  # - the constructor's field values may alias the destination (isPartOf)
+  # check if we need to construct the object in a temporary
   var useTemp =
         isRef or
-        d.k == locNone or
-        (d.t != nil and not sameBackendType(t, d.t.skipTypes(abstractInstOwned))) or
+        (d.k notin {locTemp,locLocalVar,locGlobalVar,locParam,locField}) or
         (isPartOf(d.lode, e) != arNo)
 
   var tmp: TLoc = default(TLoc)
   var r: Rope
-  let needsZeroMem =
-    nfAllFieldsSet notin e.flags or
-    (optSeqDestructors notin p.config.globalOptions and containsGarbageCollectedRef(t))
+  let needsZeroMem = p.config.selectedGC notin {gcArc, gcAtomicArc, gcOrc} or nfAllFieldsSet notin e.flags
   if useTemp:
     tmp = getTemp(p, t)
     r = rdLoc(tmp)
@@ -1961,15 +1887,15 @@ proc genSeqConstr(p: BProc, n: PNode, d: var TLoc) =
   if optSeqDestructors in p.config.globalOptions:
     let seqtype = n.typ
     let rd = rdLoc dest[]
+    let et = getTypeDesc(p.module, seqtype.elementType)
     let pt = getSeqPayloadType(p.module, seqtype)
-    let pe = seqPayloadElem(p.module, seqtype)
     p.s(cpsStmts).addFieldAssignment(rd, "len", lit)
     p.s(cpsStmts).addFieldAssignmentWithValue(rd, "p"):
       p.s(cpsStmts).addCast(ptrType(pt)):
         p.s(cpsStmts).addCall(cgsymValue(p.module, "newSeqPayload"),
           lit,
-          cSizeof(pe),
-          cAlignof(pe))
+          cSizeof(et),
+          cAlignof(et))
   else:
     # generate call to newSeq before adding the elements per hand:
     genNewSeqAux(p, dest[], lit, n.len == 0)
@@ -2002,15 +1928,15 @@ proc genArrToSeq(p: BProc, n: PNode, d: var TLoc) =
     let seqtype = n.typ
     let rd = rdLoc d
     let valL = cIntValue(L)
+    let et = getTypeDesc(p.module, seqtype.elementType)
     let pt = getSeqPayloadType(p.module, seqtype)
-    let pe = seqPayloadElem(p.module, seqtype)
     p.s(cpsStmts).addFieldAssignment(rd, "len", valL)
     p.s(cpsStmts).addFieldAssignmentWithValue(rd, "p"):
       p.s(cpsStmts).addCast(ptrType(pt)):
         p.s(cpsStmts).addCall(cgsymValue(p.module, "newSeqPayload"),
           valL,
-          cSizeof(pe),
-          cAlignof(pe))
+          cSizeof(et),
+          cAlignof(et))
   else:
     let lit = cIntLiteral(L)
     genNewSeqAux(p, d, lit, L == 0)
@@ -2151,20 +2077,12 @@ proc genRepr(p: BProc, e: PNode, d: var TLoc) =
       let ra = rdLoc(a)
       putIntoDest(p, b, e, ra & cArgumentSeparator & ra & "Len_0", a.storage)
     of tyString, tySequence:
+      let ra = rdLoc(a)
       let la = lenExpr(p, a)
-      if p.config.usesSso() and
-          skipTypes(a.t, abstractVarRange).kind == tyString:
-        let bra = byRefLoc(p, a)
-        putIntoDest(p, b, e,
-          cCall(cgsymValue(p.module, "nimStrData"), bra) &
-            cArgumentSeparator & la,
-          a.storage)
-      else:
-        let ra = rdLoc(a)
-        putIntoDest(p, b, e,
-          cIfExpr(dataFieldAccessor(p, ra), dataField(p, ra), NimNil) &
-            cArgumentSeparator & la,
-          a.storage)
+      putIntoDest(p, b, e,
+        cIfExpr(dataFieldAccessor(p, ra), dataField(p, ra), NimNil) &
+          cArgumentSeparator & la,
+        a.storage)
     of tyArray:
       let ra = rdLoc(a)
       let la = cIntValue(lengthOrd(p.config, a.t))
@@ -2745,9 +2663,9 @@ proc genConv(p: BProc, e: PNode, d: var TLoc) =
 
 proc convStrToCStr(p: BProc, n: PNode, d: var TLoc) =
   var a: TLoc = initLocExpr(p, n[0])
-  let arg = if p.config.usesSso(): byRefLoc(p, a) else: rdLoc(a)
   putIntoDest(p, d, n,
-    cgCall(p, "nimToCStringConv", arg),
+    cgCall(p, "nimToCStringConv", rdLoc(a)),
+#   "($1 ? $1->data : (NCSTRING)\"\")" % [a.rdLoc],
     a.storage)
 
 proc convCStrToStr(p: BProc, n: PNode, d: var TLoc) =
@@ -2818,38 +2736,45 @@ proc genWasMoved(p: BProc; n: PNode) =
     #  [addrLoc(p.config, a), getTypeDesc(p.module, a.t)])
 
 proc genMove(p: BProc; n: PNode; d: var TLoc) =
+  var a: TLoc = initLocExpr(p, n[1].skipAddr, {lfEnforceDeref})
   if n.len == 4:
     # generated by liftdestructors:
-    var a: TLoc = initLocExpr(p, n[1].skipAddr, {lfEnforceDeref, lfPrepareForMutation})
     var src: TLoc = initLocExpr(p, n[2])
     let destVal = rdLoc(a)
     let srcVal = rdLoc(src)
-    if p.config.usesSso() and
-        n[1].typ.skipTypes(abstractVar).kind == tyString:
-      # SmallString: destroy dst then struct-copy src; no .p field aliasing needed
+    p.s(cpsStmts).addSingleIfStmt(
+      cOp(NotEqual,
+        dotField(destVal, "p"),
+        dotField(srcVal, "p"))):
       genStmts(p, n[3])
-      genAssignment(p, a, src, {})
-    else:
-      p.s(cpsStmts).addSingleIfStmt(
-        cOp(NotEqual,
-          dotField(destVal, "p"),
-          dotField(srcVal, "p"))):
-        genStmts(p, n[3])
-      p.s(cpsStmts).addFieldAssignment(destVal, "len", dotField(srcVal, "len"))
-      p.s(cpsStmts).addFieldAssignment(destVal, "p", dotField(srcVal, "p"))
+    p.s(cpsStmts).addFieldAssignment(destVal, "len", dotField(srcVal, "len"))
+    p.s(cpsStmts).addFieldAssignment(destVal, "p", dotField(srcVal, "p"))
   else:
     if d.k == locNone: d = getTemp(p, n.typ)
-    if p.config.selectedGC in {gcArc, gcAtomicArc, gcOrc, gcYrc}:
+    if p.config.selectedGC in {gcArc, gcAtomicArc, gcOrc}:
+      genAssignment(p, d, a, {})
       var op = getAttachedOp(p.module.g.graph, n.typ, attachedWasMoved)
-      if op == nil or sfOverridden notin op.flags:
-        var a: TLoc = initLocExpr(p, n[1].skipAddr, {lfEnforceDeref, lfPrepareForMutation})
-        genAssignment(p, d, a, {})
+      if op == nil:
         resetLoc(p, a)
       else:
-        n[1] = makeAddr(n[1], p.module.idgen)
-        genCall(p, n, d)
+        var b = initLocExpr(p, newSymNode(op))
+        case skipTypes(a.t, abstractVar+{tyStatic}).kind
+        of tyOpenArray, tyVarargs: # todo fixme generated `wasMoved` hooks for
+                                   # openarrays, but it probably shouldn't?
+          let ra = rdLoc(a)
+          var s: string
+          if reifiedOpenArray(a.lode):
+            if a.t.kind in {tyVar, tyLent}:
+              s = derefField(ra, "Field0") & cArgumentSeparator & derefField(ra, "Field1")
+            else:
+              s = dotField(ra, "Field0") & cArgumentSeparator & dotField(ra, "Field1")
+          else:
+            s = ra & cArgumentSeparator & ra & "Len_0"
+          p.s(cpsStmts).addCallStmt(rdLoc(b), s)
+        else:
+          let val = if p.module.compileToCpp: rdLoc(a) else: byRefLoc(p, a)
+          p.s(cpsStmts).addCallStmt(rdLoc(b), val)
     else:
-      var a: TLoc = initLocExpr(p, n[1].skipAddr, {lfEnforceDeref, lfPrepareForMutation})
       genAssignment(p, d, a, {})
       resetLoc(p, a)
 
@@ -2860,19 +2785,15 @@ proc genDestroy(p: BProc; n: PNode) =
     case t.kind
     of tyString:
       var a: TLoc = initLocExpr(p, arg)
-      if p.config.usesSso():
-        # SmallString: delegate to nimDestroyStrV1 (rc-based, handles static strings)
-        p.s(cpsStmts).addCallStmt(cgsymValue(p.module, "nimDestroyStrV1"), rdLoc(a))
-      else:
-        let ra = rdLoc(a)
-        let rp = dotField(ra, "p")
-        p.s(cpsStmts).addSingleIfStmt(
-          cOp(And, rp,
-            cOp(Not, cOp(BitAnd, NimInt,
-              derefField(rp, "cap"),
-              NimStrlitFlag)))):
-          let fn = if optThreads in p.config.globalOptions: "deallocShared" else: "dealloc"
-          p.s(cpsStmts).addCallStmt(cgsymValue(p.module, fn), rp)
+      let ra = rdLoc(a)
+      let rp = dotField(ra, "p")
+      p.s(cpsStmts).addSingleIfStmt(
+        cOp(And, rp,
+          cOp(Not, cOp(BitAnd, NimInt,
+            derefField(rp, "cap"),
+            NimStrlitFlag)))):
+        let fn = if optThreads in p.config.globalOptions: "deallocShared" else: "dealloc"
+        p.s(cpsStmts).addCallStmt(cgsymValue(p.module, fn), rp)
     of tySequence:
       var a: TLoc = initLocExpr(p, arg)
       let ra = rdLoc(a)
@@ -2914,7 +2835,7 @@ proc genSlice(p: BProc; e: PNode; d: var TLoc) =
   let (x, y) = genOpenArraySlice(p, e, e.typ, e.typ.elementType,
     prepareForMutation = e[1].kind == nkHiddenDeref and
                          e[1].typ.skipTypes(abstractInst).kind == tyString and
-                         p.config.selectedGC in {gcArc, gcAtomicArc, gcOrc, gcYrc})
+                         p.config.selectedGC in {gcArc, gcAtomicArc, gcOrc})
   if d.k == locNone: d = getTemp(p, e.typ)
   let dest = rdLoc(d)
   p.s(cpsStmts).addFieldAssignment(dest, "Field0", x)
@@ -2977,15 +2898,8 @@ proc genMagicExpr(p: BProc, e: PNode, d: var TLoc, op: TMagic) =
   of mAppendStrStr: genStrAppend(p, e, d)
   of mAppendSeqElem:
     if optSeqDestructors in p.config.globalOptions:
-      if p.config.selectedGC in {gcArc, gcAtomicArc, gcOrc}:
-        # Inline growth + direct slot assignment: avoids the add() call overhead
-        # and lets the C compiler see the construction expression at its final
-        # destination, enabling in-place construction for nkObjConstr etc.
-        # gcYrc is excluded because its add() acquires a striped reader lock.
-        genSeqElemAppendV2(p, e, d)
-      else:
-        e[1] = makeAddr(e[1], p.module.idgen)
-        genCall(p, e, d)
+      e[1] = makeAddr(e[1], p.module.idgen)
+      genCall(p, e, d)
     else:
       genSeqElemAppend(p, e, d)
   of mEqStr: genStrEquals(p, e, d)
@@ -3125,7 +3039,7 @@ proc genMagicExpr(p: BProc, e: PNode, d: var TLoc, op: TMagic) =
       let n = semparallel.liftParallel(p.module.g.graph, p.module.idgen, p.module.module, e)
       expr(p, n, d)
   of mDeepCopy:
-    if p.config.selectedGC in {gcArc, gcAtomicArc, gcOrc, gcYrc} and optEnableDeepCopy notin p.config.globalOptions:
+    if p.config.selectedGC in {gcArc, gcAtomicArc, gcOrc} and optEnableDeepCopy notin p.config.globalOptions:
       localError(p.config, e.info,
         "for --mm:arc|atomicArc|orc 'deepcopy' support has to be enabled with --deepcopy:on")
 
@@ -3241,8 +3155,6 @@ proc genTupleConstr(p: BProc, n: PNode, d: var TLoc) =
     for i in 0..<n.len:
       var it = n[i]
       if it.kind == nkExprColonExpr: it = it[1]
-      # Do not produce code for void types
-      if it.typ != nil and isEmptyType(it.typ): continue
       rec = initLoc(locExpr, it, dest[].storage)
       rec.snippet = dotField(rdLoc(dest[]), "Field" & rope(i))
       rec.flags.incl(lfEnforceDeref)
@@ -3359,11 +3271,7 @@ proc upConv(p: BProc, n: PNode, d: var TLoc) =
         p.s(cpsStmts).addCallStmt(cgsymValue(p.module, "raiseObjectConversionError"))
         raiseInstr(p, p.s(cpsStmts))
 
-  # skip cast when types map to the same C type
-  # this avoids invalid C code like `*(T*)&x` for types that can't have their address taken (e.g., WASM __externref_t)
-  if getTypeDesc(p.module, n.typ) == getTypeDesc(p.module, n[0].typ):
-    expr(p, n[0], d)
-  elif n[0].typ.kind != tyObject:
+  if n[0].typ.kind != tyObject:
     let destTyp = getTypeDesc(p.module, n.typ)
     let val = rdLoc(a)
     if n.isLValue:
@@ -3409,7 +3317,7 @@ proc downConv(p: BProc, n: PNode, d: var TLoc) =
         cCast(ptrType(destType),
           wrapPar(cAddr(wrapPar(val))))),
       a.storage)
-  elif p.module.compileToCpp or isImportedType(src):
+  elif p.module.compileToCpp:
     # C++ implicitly downcasts for us
     expr(p, arg, d)
   else:
@@ -3491,23 +3399,7 @@ proc genConstDefinition(q: BModule; p: BProc; sym: PSym) =
   data.addDeclWithVisibility(Private):
     data.addVarWithInitializer(Local, actualConstName, typ = td):
       genBracedInit(q.initProc, sym.astdef, isConst = true, sym.typ, data)
-  if q.config.cmd == cmdNifC:
-    # Each `cg` process that demands this const emits its definition
-    # (emit-everywhere). Always declare it first (the data analogue of a proc
-    # prototype) so a TU whose copy the merge stage drops still has a valid
-    # declaration; wrap the definition as a droppable `'d'` unit the merge
-    # stage assigns to a single owner.
-    let cname = stripCnifMarks(actualConstName)
-    var decl = newBuilder("")
-    decl.addDeclWithVisibility(Extern):
-      decl.addVar(kind = Local, name = actualConstName, typ = td)
-    q.s[cfsData].add(extract(decl))
-    q.s[cfsData].add(cnifDefDirective(cname, "d", icNifName(q, sym)))
-    q.s[cfsData].add(extract(data))
-    q.s[cfsData].add(cnifEndDefs())
-    q.icDataDefs.add (cname, icNifName(q, sym))
-  else:
-    q.s[cfsData].add(extract(data))
+  q.s[cfsData].add(extract(data))
   if q.hcrOn:
     # generate the global pointer with the real name
     q.s[cfsVars].addVar(kind = Global, name = sym.loc.snippet,
@@ -3571,17 +3463,6 @@ proc expr(p: BProc, n: PNode, d: var TLoc) =
     of skProc, skConverter, skIterator, skFunc:
       #if sym.kind == skIterator:
       #  echo renderTree(sym.getBody, {renderIds})
-      if p.config.cmd == cmdNifC and
-          (isGenericRoutineStrict(sym) or sfCompileTime in sym.flags or
-           (sym.kind == skIterator and sym.typ.callConv == ccInline)):
-        # Under IC a module's top-level routine definitions are serialized as bare
-        # symbol references that reappear in the loaded statement list. Uninstantiated
-        # generic routines (incl. those with type-class params like `tuple`) and
-        # `.compileTime` routines have no run-time code, so skip them here.
-        # Inline iterators likewise have no standalone code — they are always inlined
-        # at their for-loop call sites by the transformer (only closure iterators get
-        # a standalone C function), so a bare serialized def reference is a no-op.
-        return
       if sfCompileTime in sym.flags:
         localError(p.config, n.info, "request to generate code for .compileTime proc: " &
            sym.name.s)
@@ -3656,11 +3537,6 @@ proc expr(p: BProc, n: PNode, d: var TLoc) =
         # echo renderTree(p.prc.ast, {renderIds})
         internalError(p.config, n.info, "expr: param not init " & sym.name.s & "_" & $sym.id)
       putLocIntoDest(p, d, sym.loc)
-    of skTemplate, skMacro:
-      # Under IC a module's top-level template/macro definitions are serialized as
-      # bare symbol references (only their interface matters), so they reappear in
-      # the loaded statement list. They are compile-time only and produce no code.
-      discard
     else: internalError(p.config, n.info, "expr(" & $sym.kind & "); unknown symbol")
   of nkNilLit:
     if not isEmptyType(n.typ):
@@ -3886,7 +3762,6 @@ proc containsOpaqueImportcField(typ: PType): bool =
       return true
   of tyTuple:
     for i, a in t.ikids:
-      if isEmptyType(a): continue
       if containsOpaqueImportcField(a):
         return true
   of tyArray:
@@ -3936,12 +3811,10 @@ proc getDefaultValue(p: BProc; typ: PType; info: TLineInfo; result: var Builder)
     var tupleInit: StructInitializer
     let initKind = if containsOpaqueImportcField(t): siNamedStruct else: siOrderedStruct
     result.addStructInitializer(tupleInit, kind = initKind):
-      if p.vccAndC and validTupleTypeFields(t) == 0:
+      if p.vccAndC and t.isEmptyTupleType:
         result.addField(tupleInit, name = "dummy"):
           result.addIntValue(0)
       for i, a in t.ikids:
-        # Do not produce code for void types
-        if isEmptyType(a): continue
         let elemTyp = skipTypes(a, abstractRange+{tyOwned}-{tyTypeDesc})
         if not isOpaqueImportcType(elemTyp):
           result.addField(tupleInit, name = "Field" & $i):
@@ -4116,8 +3989,6 @@ proc genConstTuple(p: BProc, n: PNode; isConst: bool; tup: PType; result: var Bu
       var it = n[i]
       if it.kind == nkExprColonExpr:
         it = it[1]
-      # Do not produce code for void types
-      if isEmptyType(tup[i]): continue
       result.addField(tupleInit, name = "Field" & $i):
         genBracedInit(p, it, isConst, tup[i], result)
 
@@ -4264,10 +4135,7 @@ proc genBracedInit(p: BProc, n: PNode; isConst: bool; optionalType: PType; resul
       genConstObjConstr(p, n, isConst, result)
     of tyString, tyCstring:
       if optSeqDestructors in p.config.globalOptions and n.kind != nkNilLit and ty == tyString:
-        if p.config.usesSso():
-          genStringLiteralV3Const(p.module, n, isConst, result)
-        else:
-          genStringLiteralV2Const(p.module, n, isConst, result)
+        genStringLiteralV2Const(p.module, n, isConst, result)
       else:
         var d: TLoc = initLocExpr(p, n)
         result.add rdLoc(d)

compiler/ccgliterals.nim

@@ -16,17 +16,13 @@
 ## implementation.
 
 template detectVersion(field, corename) =
-  if m.g.config.selectedGC in {gcArc, gcOrc, gcYrc, gcAtomicArc, gcHooks}:
+  if m.g.config.selectedGC in {gcArc, gcOrc, gcAtomicArc, gcHooks}:
     result = 2
   else:
     result = 1
 
 proc detectStrVersion(m: BModule): int =
-  if m.g.config.usesSso() and
-      m.g.config.selectedGC in {gcArc, gcOrc, gcYrc, gcAtomicArc, gcHooks}:
-    result = 3
-  else:
-    detectVersion(strVersion, "nimStrVersion")
+  detectVersion(strVersion, "nimStrVersion")
 
 proc detectSeqVersion(m: BModule): int =
   detectVersion(seqVersion, "nimSeqVersion")
@@ -132,192 +128,6 @@ proc genStringLiteralV2Const(m: BModule; n: PNode; isConst: bool; result: var Bu
     result.addField(strInit, name = "p"):
       result.add(cCast(ptrType("NimStrPayload"), cAddr(pureLit)))
 
-proc ssoCharLit(ch: char): string =
-  ## Return a C char literal for ch, with proper escaping.
-  const hexDigits = "0123456789abcdef"
-  result = "'"
-  case ch
-  of '\'': result.add("\\'")
-  of '\\': result.add("\\\\")
-  of '\0': result.add("\\0")
-  of '\n': result.add("\\n")
-  of '\r': result.add("\\r")
-  of '\t': result.add("\\t")
-  elif ch.ord < 32 or ch.ord == 127:
-    result.add("\\x")
-    result.add(hexDigits[ch.ord shr 4])
-    result.add(hexDigits[ch.ord and 0xf])
-  else:
-    result.add(ch)
-  result.add('\'')
-
-proc ssoBytesLit(m: BModule; s: string; slen: int): string =
-  ## Compute the `bytes` field value for the new SmallString layout.
-  ## byte 0 = slen, bytes 1-7 = inline chars 0-6 (zero-padded).
-  ## On LE: slen in bits 0-7, char[i] in bits (i+1)*8..(i+1)*8+7.
-  ## On BE: slen in bits 56-63, char[i] in bits (6-i)*8..(6-i)*8+7.
-  const AlwaysAvail = 7
-  var val: uint64
-  if CPU[m.g.config.target.targetCPU].endian == littleEndian:
-    val = uint64(slen)
-    for i in 0..<min(s.len, AlwaysAvail):
-      val = val or (uint64(s[i]) shl (uint(i + 1) * 8))
-  else:
-    val = uint64(slen) shl 56
-    for i in 0..<min(s.len, AlwaysAvail):
-      val = val or (uint64(s[i]) shl (uint(AlwaysAvail - 1 - i) * 8))
-  # Cast to NU (C name for Nim's uint, = NU64 on 64-bit). NU64 = uint64_t.
-  result = cCast("NU", $val & "ULL")
-
-proc ssoMoreLit(m: BModule; s: string): string =
-  ## For medium string literals (AlwaysAvail < len <= PayloadSize), encode
-  ## chars[AlwaysAvail..ptrSize-1] in the 'more' pointer field bit-pattern.
-  ## The last pointer byte is always '\0' (null terminator), guaranteed by
-  ## PayloadSize = AlwaysAvail + ptrSize - 1.  slen <= PayloadSize guards
-  ## prevent any code from dereferencing this as an actual pointer.
-  const AlwaysAvail = 7
-  let ptrSize = m.g.config.target.ptrSize
-  var val: uint64 = 0
-  for i in 0..<ptrSize:
-    let ch: uint64 = if AlwaysAvail + i < s.len: uint64(s[AlwaysAvail + i]) else: 0
-    if CPU[m.g.config.target.targetCPU].endian == littleEndian:
-      val = val or (ch shl (uint(i) * 8))
-    else:
-      val = val or (ch shl (uint(ptrSize - 1 - i) * 8))
-  result = cCast(ptrType("LongString"), "(uintptr_t)" & $val)
-
-proc genStringLiteralV3Const(m: BModule; n: PNode; isConst: bool; result: var Builder) =
-  # Inline SmallString struct initializer for use inside const aggregate types.
-  # Layout: {bytes: NimUint, more: ptr LongString}
-  # bytes = slen (low byte) | char[0]<<8 | char[1]<<16 | ... | char[6]<<56
-  const AlwaysAvail = 7
-  let s = n.strVal
-
-  cgsym(m, "SmallString")
-  cgsym(m, "LongString")
-
-  let payloadSize = AlwaysAvail + m.g.config.target.ptrSize - 1
-  var si: StructInitializer
-  result.addStructInitializer(si, kind = siOrderedStruct):
-    if s.len <= AlwaysAvail:
-      result.addField(si, name = "bytes"):
-        result.add(ssoBytesLit(m, s, s.len))
-      result.addField(si, name = "more"):
-        result.add(NimNil)
-    elif s.len <= payloadSize:
-      # Medium string: bytes holds slen + chars 0-6; more holds chars 7..PayloadSize-1.
-      result.addField(si, name = "bytes"):
-        result.add(ssoBytesLit(m, s, s.len))
-      result.addField(si, name = "more"):
-        result.add(ssoMoreLit(m, s))
-    else:
-      # Emit the LongString block into cfsStrData and reference it inline.
-      let dataName = getTempName(m)
-      var res = newBuilder("")
-      res.addVarWithTypeAndInitializer(
-          if isConst: AlwaysConst else: Global,
-          name = dataName):
-        res.addSimpleStruct(m, name = "", baseType = ""):
-          res.addField(name = "rc", typ = NimInt)
-          res.addField(name = "fullLen", typ = NimInt)
-          res.addField(name = "capImpl", typ = NimInt)
-          res.addArrayField(name = "data", elementType = NimChar, len = s.len + 1)
-      do:
-        var di: StructInitializer
-        res.addStructInitializer(di, kind = siOrderedStruct):
-          res.addField(di, name = "fullLen"):
-            res.addIntValue(s.len)
-          res.addField(di, name = "rc"):
-            res.addIntValue(1)
-          res.addField(di, name = "capImpl"):
-            res.addIntValue(0)  # static, never freed
-          res.addField(di, name = "data"):
-            res.add(makeCString(s))
-      m.s[cfsStrData].add(extract(res))
-      # slen = StaticSlen (254): marks this as a static (never-freed) long string.
-      result.addField(si, name = "bytes"):
-        result.add(ssoBytesLit(m, s, 254))
-      result.addField(si, name = "more"):
-        result.add(cCast(ptrType("LongString"), cAddr(dataName)))
-
-# ------ Version 3: SmallString (SSO) strings --------------------------------
-
-proc genStringLiteralV3(m: BModule; n: PNode; isConst: bool; result: var Builder) =
-  # SmallString literal. Always generate a fresh SmallString variable (like v2
-  # always generates a fresh outer NimStringV2). For long strings, cache the
-  # LongString payload to avoid duplicates within a module.
-  const AlwaysAvail = 7  # must match strs_v3.nim
-  let s = n.strVal
-  let tmp = getTempName(m)
-  result.add tmp
-
-  cgsym(m, "SmallString")
-  cgsym(m, "LongString")
-
-  let payloadSize = AlwaysAvail + m.g.config.target.ptrSize - 1
-  var res = newBuilder("")
-  if s.len <= AlwaysAvail:
-    # Short: bytes holds slen + all chars (zero-padded), more = NULL.
-    res.addVarWithInitializer(
-        if isConst: AlwaysConst else: Global,
-        name = tmp, typ = "SmallString"):
-      var si: StructInitializer
-      res.addStructInitializer(si, kind = siOrderedStruct):
-        res.addField(si, name = "bytes"):
-          res.add(ssoBytesLit(m, s, s.len))
-        res.addField(si, name = "more"):
-          res.add(NimNil)
-  elif s.len <= payloadSize:
-    # Medium: bytes holds slen + chars 0-6; more holds chars 7..PayloadSize-1 as raw bits.
-    res.addVarWithInitializer(
-        if isConst: AlwaysConst else: Global,
-        name = tmp, typ = "SmallString"):
-      var si: StructInitializer
-      res.addStructInitializer(si, kind = siOrderedStruct):
-        res.addField(si, name = "bytes"):
-          res.add(ssoBytesLit(m, s, s.len))
-        res.addField(si, name = "more"):
-          res.add(ssoMoreLit(m, s))
-  else:
-    # Long: cache the LongString block to emit it only once per module per string.
-    # Always generate a fresh SmallString pointing at the (possibly cached) block.
-    let id = nodeTableTestOrSet(m.dataCache, n, m.labels)
-    var dataName: string
-    if id == m.labels:
-      dataName = getTempName(m)
-      res.addVarWithTypeAndInitializer(
-          if isConst: AlwaysConst else: Global,
-          name = dataName):
-        res.addSimpleStruct(m, name = "", baseType = ""):
-          res.addField(name = "rc", typ = NimInt)
-          res.addField(name = "fullLen", typ = NimInt)
-          res.addField(name = "capImpl", typ = NimInt)
-          res.addArrayField(name = "data", elementType = NimChar, len = s.len + 1)
-      do:
-        var di: StructInitializer
-        res.addStructInitializer(di, kind = siOrderedStruct):
-          res.addField(di, name = "fullLen"):
-            res.addIntValue(s.len)
-          res.addField(di, name = "rc"):
-            res.addIntValue(1)
-          res.addField(di, name = "capImpl"):
-            res.addIntValue(0)  # bit 0 = 0: static, never freed
-          res.addField(di, name = "data"):
-            res.add(makeCString(s))
-    else:
-      dataName = m.tmpBase & $id
-    # slen = StaticSlen (254): marks this as a static (never-freed) long string.
-    res.addVarWithInitializer(
-        if isConst: AlwaysConst else: Global,
-        name = tmp, typ = "SmallString"):
-      var si: StructInitializer
-      res.addStructInitializer(si, kind = siOrderedStruct):
-        res.addField(si, name = "bytes"):
-          res.add(ssoBytesLit(m, s, 254))
-        res.addField(si, name = "more"):
-          res.add(cCast(ptrType("LongString"), cAddr(dataName)))
-  m.s[cfsStrData].add(extract(res))
-
 # ------ Version selector ---------------------------------------------------
 
 proc genStringLiteralDataOnly(m: BModule; s: string; info: TLineInfo;
@@ -328,8 +138,6 @@ proc genStringLiteralDataOnly(m: BModule; s: string; info: TLineInfo;
     let tmp = getTempName(m)
     genStringLiteralDataOnlyV2(m, s, tmp, isConst)
     result.add tmp
-  of 3:
-    localError(m.config, info, "genStringLiteralDataOnly not supported for SmallString (nimsso)")
   else:
     localError(m.config, info, "cannot determine how to produce code for string literal")
 
@@ -340,6 +148,5 @@ proc genStringLiteral(m: BModule; n: PNode; result: var Builder) =
   case detectStrVersion(m)
   of 0, 1: genStringLiteralV1(m, n, result)
   of 2: genStringLiteralV2(m, n, isConst = true, result)
-  of 3: genStringLiteralV3(m, n, isConst = true, result)
   else:
     localError(m.config, n.info, "cannot determine how to produce code for string literal")

compiler/ccgstmts.nim

@@ -230,7 +230,7 @@ proc blockLeaveActions(p: BProc, howManyTrys, howManyExcepts: int, isReturnStmt
   # Called by return and break stmts.
   # Deals with issues faced when jumping out of try/except/finally stmts.
 
-  var stack = newSeq[tuple[fin: PNode, inExcept: bool, isHidden: bool, label: Natural]](0)
+  var stack = newSeq[tuple[fin: PNode, inExcept: bool, label: Natural]](0)
 
   inc p.withinBlockLeaveActions
   for i in 1..howManyTrys:
@@ -341,9 +341,9 @@ proc genCppParamsForCtor(p: BProc; call: PNode; didGenTemp: var bool): Snippet =
           call[i][0]
         else:
           call[i]
-      if not param.typ.isCompileTimeOnly and (param.kind != nkBracketExpr or param.typ.kind in
+      if param.kind != nkBracketExpr or param.typ.kind in
         {tyRef, tyPtr, tyUncheckedArray, tyArray, tyOpenArray,
-          tyVarargs, tySequence, tyString, tyCstring, tyTuple}):
+          tyVarargs, tySequence, tyString, tyCstring, tyTuple}:
         let tempLoc = initLocExprSingleUse(p, param)
         didGenTemp = didGenTemp or tempLoc.k == locTemp
       genOtherArg(p, call, i, typ, res, argBuilder)
@@ -836,26 +836,12 @@ proc raiseExitCleanup(p: BProc, destroy: string) =
         p.s(cpsStmts).addGoto("LA" & $p.nestedTryStmts[^1].label & "_")
 
 proc finallyActions(p: BProc) =
-  if p.config.exc != excGoto:
-    # Walk past compiler-injected `nkHiddenTryStmt` wrappers (e.g. ARC's
-    # destructor try/finally that wraps `except T as e:` bodies) to reach
-    # the user's actual try.  We must NOT walk past a real user try whose
-    # body we are currently in, because a raise from there will be caught
-    # by that try's own except branches rather than escaping outward.
-    #
-    # If after skipping wrappers the next entry is a user try in its
-    # except branch (inExcept=true), inline its finally body before the
-    # raise propagates — without this, the C++ sibling-catch rule would
-    # cause the user's catch(...)/finally pair to be bypassed and the
-    # finally would be silently dropped.
-    for i in countdown(p.nestedTryStmts.high, 0):
-      if p.nestedTryStmts[i].isHidden:
-        continue
-      if p.nestedTryStmts[i].inExcept:
-        let finallyBlock = p.nestedTryStmts[i].fin
-        if finallyBlock != nil:
-          genSimpleBlock(p, finallyBlock[0])
-      return
+  if p.config.exc != excGoto and p.nestedTryStmts.len > 0 and p.nestedTryStmts[^1].inExcept:
+    # if the current try stmt have a finally block,
+    # we must execute it before reraising
+    let finallyBlock = p.nestedTryStmts[^1].fin
+    if finallyBlock != nil:
+      genSimpleBlock(p, finallyBlock[0])
 
 proc raiseInstr(p: BProc; result: var Builder) =
   if p.config.exc == excGoto:
@@ -1179,7 +1165,7 @@ proc genTryCpp(p: BProc, t: PNode, d: var TLoc) =
         throw;
       }
     } catch(...) {
-      // C++ exception occurred, not under Nim's control.
+      // C++ exception occured, not under Nim's control.
     }
     {
       /* finally: */
@@ -1199,7 +1185,7 @@ proc genTryCpp(p: BProc, t: PNode, d: var TLoc) =
   lineCg(p, cpsLocals, "std::exception_ptr T$1_;$n", [etmp])
 
   let fin = if t[^1].kind == nkFinally: t[^1] else: nil
-  p.nestedTryStmts.add((fin, false, t.kind == nkHiddenTryStmt, 0.Natural))
+  p.nestedTryStmts.add((fin, false, 0.Natural))
 
   if t.kind == nkHiddenTryStmt:
     lineCg(p, cpsStmts, "try {$n", [])
@@ -1237,7 +1223,6 @@ proc genTryCpp(p: BProc, t: PNode, d: var TLoc) =
         else:
           scope = initScope(p.s(cpsStmts))
       # we handled the error:
-      linefmt(p, cpsStmts, "T$1_ = nullptr;$n", [etmp])
       expr(p, t[i][0], d)
       linefmt(p, cpsStmts, "#popCurrentException();$n", [])
       endBlockWith(p):
@@ -1386,7 +1371,7 @@ proc genTryCppOld(p: BProc, t: PNode, d: var TLoc) =
   genLineDir(p, t)
   cgsym(p.module, "popCurrentExceptionEx")
   let fin = if t[^1].kind == nkFinally: t[^1] else: nil
-  p.nestedTryStmts.add((fin, false, t.kind == nkHiddenTryStmt, 0.Natural))
+  p.nestedTryStmts.add((fin, false, 0.Natural))
   startBlockWith(p):
     p.s(cpsStmts).add("try {\n")
   expr(p, t[0], d)
@@ -1465,7 +1450,7 @@ proc genTryGoto(p: BProc; t: PNode; d: var TLoc) =
   let lab = p.labels
   let hasExcept = t[1].kind == nkExceptBranch
   if hasExcept: inc p.withinTryWithExcept
-  p.nestedTryStmts.add((fin, false, t.kind == nkHiddenTryStmt, Natural lab))
+  p.nestedTryStmts.add((fin, false, Natural lab))
 
   p.flags.incl nimErrorFlagAccessed
 
@@ -1671,7 +1656,7 @@ proc genTrySetjmp(p: BProc, t: PNode, d: var TLoc) =
     initElifBranch(p.s(cpsStmts), nonQuirkyIf, removeSinglePar(
       cOp(Equal, dotField(safePoint, "status"), cIntValue(0))))
   let fin = if t[^1].kind == nkFinally: t[^1] else: nil
-  p.nestedTryStmts.add((fin, quirkyExceptions, t.kind == nkHiddenTryStmt, 0.Natural))
+  p.nestedTryStmts.add((fin, quirkyExceptions, 0.Natural))
   expr(p, t[0], d)
   var quirkyIf = default(IfBuilder)
   var quirkyScope = default(ScopeBuilder)
@@ -1955,15 +1940,6 @@ proc genAsgn(p: BProc, e: PNode, fastAsgn: bool) =
   elif optFieldCheck in p.options and isDiscriminantField(e[0]):
     genLineDir(p, e)
     asgnFieldDiscriminant(p, e)
-  elif p.config.usesSso() and e[0].kind == nkBracketExpr and
-      e[0][0].typ.skipTypes(abstractVar).kind == tyString:
-    # nimsso: s[i] = c  →  nimStrPutV3(&s, i, c)  (handles COW internally)
-    genLineDir(p, e)
-    var base = initLocExpr(p, e[0][0])
-    var idx  = initLocExpr(p, e[0][1])
-    var rhs  = initLocExpr(p, e[1])
-    p.s(cpsStmts).addCallStmt(cgsymValue(p.module, "nimStrPutV3"),
-      byRefLoc(p, base), rdLoc(idx), rdCharLoc(rhs))
   else:
     let le = e[0]
     let ri = e[1]
@@ -1986,9 +1962,4 @@ proc genStmts(p: BProc, t: PNode) =
   if isPush: pushInfoContext(p.config, t.info)
   expr(p, t, a)
   if isPush: popInfoContext(p.config)
-  # A bare `nkSym` statement is how IC serializes a definition that lives inside a
-  # top-level block (e.g. a nested `proc`/`var`): codegen emits the definition and
-  # leaves the symbol's own location in `a` (e.g. `locProc`), which is discarded
-  # here, so the value-sanity check below does not apply to it.
-  internalAssert p.config, t.kind == nkSym or
-    a.k in {locNone, locTemp, locLocalVar, locExpr}
+  internalAssert p.config, a.k in {locNone, locTemp, locLocalVar, locExpr}

compiler/ccgtypes.nim

@@ -72,37 +72,6 @@ proc mangleProc(m: BModule; s: PSym; makeUnique: bool): string =
   else:
     m.g.mangledPrcs.incl(result)
 
-proc sharedInstanceCName(m: BModule; s: PSym): string =
-  ## The module-free canonical C name for a content-keyed generic instance,
-  ## or "" when the symbol must keep its module-suffixed name. With a shared
-  ## name, every TU that instantiated the same generic with the same type
-  ## arguments calls one extern definition (first claimant's TU embeds it,
-  ## see `genProcLvl3`) instead of compiling its own static copy.
-  ##
-  ## The name is program-unique only if the 30-bit content hash does not
-  ## collide for same-named instances of *different* instantiations across
-  ## modules — the per-module probe in `setInstanceDisamb` cannot see that.
-  ## Claimants therefore must present the same signature; on mismatch the
-  ## later one keeps its module-suffixed name (no merge, still correct).
-  ## Residual risk: same name and signature, different generic args, AND a
-  ## 30-bit collision — vanishingly unlikely; a full-typeKey verification
-  ## channel can close it later.
-  result = ""
-  if m.config.cmd == cmdNifC and s.kind in routineKinds and
-      (s.disamb and InstanceDisambBit) != 0'i32 and
-      s.typ != nil and s.typ.callConv != ccInline and not m.hcrOn and
-      {sfImportc, sfExportc, sfCodegenDecl} * s.flags == {}:
-    # The content-derived `disamb` is unique per process (collision-probed in
-    # `setInstanceDisamb`), so the mint-site-independent `_i<disamb>` name is
-    # safe to use directly; identical instances across modules collide on it
-    # exactly and the merge stage keeps one.
-    result = s.name.s.mangle & "_i" & $s.disamb
-
-proc isSharedInstanceCName(m: BModule; s: PSym): bool =
-  m.config.cmd == cmdNifC and s.kind in routineKinds and
-    (s.disamb and InstanceDisambBit) != 0'i32 and
-    stripCnifMarks(s.loc.snippet) == s.name.s.mangle & "_i" & $s.disamb
-
 proc fillBackendName(m: BModule; s: PSym) =
   if s.loc.snippet == "":
     var result: Rope
@@ -110,22 +79,13 @@ proc fillBackendName(m: BModule; s: PSym) =
       m.g.config.symbolFiles == disabledSf:
       result = mangleProc(m, s, false).rope
     else:
-      let shared = sharedInstanceCName(m, s)
-      if shared.len > 0:
-        result = shared.rope
-      else:
-        result = s.name.s.mangle.rope
-        result.add mangleProcNameExt(m.g.graph, s)
+      result = s.name.s.mangle.rope
+      result.add mangleProcNameExt(m.g.graph, s)
     if m.hcrOn:
       result.add '_'
       result.add(idOrSig(s, m.module.name.s.mangle, m.sigConflicts, m.config))
     backendEnsureMutable s
-    if m.config.cmd == cmdNifC:
-      # mark the name so the cnif artifact writer can turn every occurrence
-      # into a Symbol token; stripped from the actual C output in genModule
-      s.locImpl.snippet = markCName(result)
-    else:
-      s.locImpl.snippet = result
+    s.locImpl.snippet = result
 
 proc fillParamName(m: BModule; s: PSym) =
   if s.loc.snippet == "":
@@ -317,7 +277,7 @@ proc isInvalidReturnType(conf: ConfigRef; typ: PType, isProc = true): bool =
     of ctStruct:
       let t = skipTypes(rettype, typedescInst)
       if rettype.isImportedCppType or t.isImportedCppType or
-          (typ.callConv == ccCDecl and conf.selectedGC in {gcArc, gcAtomicArc, gcOrc, gcYrc}):
+          (typ.callConv == ccCDecl and conf.selectedGC in {gcArc, gcAtomicArc, gcOrc}):
         # prevents nrvo for cdecl procs; # bug #23401
         result = false
       else:
@@ -334,12 +294,7 @@ proc cacheGetType(tab: TypeCache; sig: SigHash): Rope =
   result = tab.getOrDefault(sig)
 
 proc addAbiCheck(m: BModule; t: PType, name: Rope) =
-  if isDefined(m.config, "checkAbi") and (let size = getSize(m.config, t); size != szUnknownSize) and
-    not (t.kind == tyObject and searchTypeFor(t, proc (t: PType): bool {.nimcall.} = t.kind == tyUncheckedArray)):
-    # `UncheckedArray`, not `ptr UncheckedArray` type field in object types is a flexible array.
-    # `sizeof` in C and Nim doesn't always return the same value for object types containing it.
-    # making `getSize` in Nim always returns the same value as `sizeof` in C from flexible arrays seems hard.
-    # See `SEQ_DECL_SIZE` in lib/nimbase.h
+  if isDefined(m.config, "checkAbi") and (let size = getSize(m.config, t); size != szUnknownSize):
     var msg = "backend & Nim disagree on size for: "
     msg.addTypeHeader(m.config, t)
     var msg2 = ""
@@ -349,7 +304,7 @@ proc addAbiCheck(m: BModule; t: PType, name: Rope) =
 
 
 proc fillResult(conf: ConfigRef; param: PNode, proctype: PType) =
-  backendEnsureMutable param.sym
+  ensureMutable param.sym
   fillLoc(param.sym.locImpl, locParam, param, "Result",
           OnStack)
   let t = param.sym.typ
@@ -379,10 +334,6 @@ proc getSimpleTypeDesc(m: BModule; typ: PType): Rope =
       cgsym(m, "NimStrPayload")
       cgsym(m, "NimStringV2")
       result = typeNameOrLiteral(m, typ, "NimStringV2")
-    of 3:
-      cgsym(m, "LongString")
-      cgsym(m, "SmallString")
-      result = typeNameOrLiteral(m, typ, "SmallString")
     else:
       cgsym(m, "NimStringDesc")
       result = typeNameOrLiteral(m, typ, "NimStringDesc*")
@@ -413,12 +364,6 @@ proc getSimpleTypeDesc(m: BModule; typ: PType): Rope =
       m.typeCache[sig] = result
 
 proc pushType(m: BModule; typ: PType) =
-  when defined(icDbgRefc):
-    if typ.kind == tySequence and
-        typ.elementType.skipTypes({tyGenericInst, tyAlias, tySink}).kind == tyGenericParam:
-      echo "[icRefc] pushType seq-of-genericparam t=", typeToString(typ),
-        " itemId=", typ.itemId.module, ".", typ.itemId.item, " mod=", m.module.name.s
-      echo getStackTrace()
   for i in 0..high(m.typeStack):
     # pointer equality is good enough here:
     if m.typeStack[i] == typ: return
@@ -503,14 +448,6 @@ proc getSeqPayloadType(m: BModule; t: PType): Rope =
   result = getTypeDescWeak(m, t, check, dkParam) & "_Content"
   #result = getTypeForward(m, t, hashType(t)) & "_Content"
 
-proc seqPayloadElem(m: BModule; t: PType): Snippet =
-  ## Returns the C type name for a seq's element as stored in the payload,
-  ## suitable for sizeof()/alignof(). Must use dkVar, not the dkParam default,
-  ## because reified openArrays (experimental views) differ: dkParam gives a
-  ## bare pointer (T*) while dkVar gives the two-word struct actually stored.
-  var check = initIntSet()
-  result = getTypeDescAux(m, t.elementType, check, dkVar)
-
 proc seqV2ContentType(m: BModule; t: PType; check: var IntSet) =
   let sig = hashType(t, m.config)
   let result = cacheGetType(m.typeCache, sig)
@@ -592,7 +529,7 @@ proc genMemberProcParams(m: BModule; prc: PSym, superCall, rettype, name, params
   var types, names, args: seq[string] = @[]
   if not isCtor:
     var this = t.n[1].sym
-    backendEnsureMutable this
+    ensureMutable this
     fillParamName(m, this)
     fillLoc(this.locImpl, locParam, t.n[1],
             this.paramStorageLoc)
@@ -614,7 +551,7 @@ proc genMemberProcParams(m: BModule; prc: PSym, superCall, rettype, name, params
       else:
         descKind = dkRefParam
     var typ, name: string
-    backendEnsureMutable param
+    ensureMutable param
     fillParamName(m, param)
     fillLoc(param.locImpl, locParam, t.n[i],
             param.paramStorageLoc)
@@ -664,18 +601,6 @@ proc genProcParams(m: BModule; t: PType, rettype: var Rope, params: var Builder,
     for i in 1..<t.n.len:
       if t.n[i].kind != nkSym: internalError(m.config, t.n.info, "genProcParams")
       var param = t.n[i].sym
-      # The hidden closure environment param (`:envP`) is not a real C parameter:
-      # the environment is passed via the trailing `ClE_0` (added below) and
-      # `closureSetup` materialises `:envP` as a local cast of it. In a from-source
-      # build `:envP` only lives in the routine's AST params, never in the proc
-      # *type's* `n`, so it never reaches here. Under IC `closureParams` re-shares
-      # the AST param node with `typ.n`, so the lifted `:envP` leaks into `t.n`;
-      # emitting it would produce a bogus extra parameter that collides with the
-      # `closureSetup` local (the "redeclared as different kind of symbol" / env
-      # pointer-type mismatch). We still must fill its name/loc (later passes such
-      # as `assignParam` and `closureSetup` reference it), but it is omitted from
-      # the C signature to match the from-source ABI.
-      let isClosureEnv = t.callConv == ccClosure and param.name.s == ":envP"
       var descKind = dkParam
       if m.config.backend == backendCpp and optByRef in param.options:
         if param.typ.kind == tyGenericInst:
@@ -687,7 +612,6 @@ proc genProcParams(m: BModule; t: PType, rettype: var Rope, params: var Builder,
       fillParamName(m, param)
       fillLoc(param.locImpl, locParam, t.n[i],
               param.paramStorageLoc)
-      if isClosureEnv: continue  # name/loc filled, but not part of the C signature
       var typ: Rope
       if ccgIntroducedPtr(m.config, param, t.returnType) and descKind == dkParam:
         typ = ptrType(getTypeDescWeak(m, param.typ, check, descKind))
@@ -871,8 +795,6 @@ proc getTupleDesc(m: BModule; typ: PType, name: Rope,
   var res = newBuilder("")
   res.addStruct(m, typ, name, ""):
     for i, a in typ.ikids:
-      # Do not produce code for void types
-      if isEmptyType(a): continue
       res.addField(
         name = "Field" & $i,
         typ = getTypeDescAux(m, a, check, dkField))
@@ -1145,7 +1067,6 @@ proc getTypeDescAux(m: BModule; origTyp: PType, check: var IntSet; kind: TypeDes
                       else: getTupleDesc(m, t, result, check)
         if not isImportedType(t):
           m.s[cfsTypes].add(recdesc)
-          addAbiCheck(m, t, result)
         elif tfIncompleteStruct notin t.flags:
           discard # addAbiCheck(m, t, result) # already handled elsewhere
   of tySet:
@@ -1167,11 +1088,6 @@ proc getTypeDescAux(m: BModule; origTyp: PType, check: var IntSet; kind: TypeDes
      tyUserTypeClass, tyUserTypeClassInst, tyInferred:
     result = getTypeDescAux(m, skipModifier(t), check, kind)
   else:
-    when defined(icDbgRefc):
-      echo "[icRefc] getTypeDescAux ", t.kind, " t=", typeToString(t),
-        " origTyp=", typeToString(origTyp), " t.itemId=", t.itemId.module, ".", t.itemId.item,
-        " sym=", (if t.sym != nil: t.sym.name.s else: "nil"),
-        " owner=", (if t.owner != nil: t.owner.name.s else: "nil")
     internalError(m.config, "getTypeDescAux(" & $t.kind & ')')
     result = ""
   # fixes bug #145:
@@ -1210,10 +1126,6 @@ proc finishTypeDescriptions(m: BModule) =
   var check = initIntSet()
   while i < m.typeStack.len:
     let t = m.typeStack[i]
-    when defined(icDbgRefc):
-      echo "[icRefc] finishTypeDescriptions[", i, "] mod=", m.module.name.s,
-        " t=", typeToString(t), " kind=", t.kind,
-        " itemId=", t.itemId.module, ".", t.itemId.item
     if optSeqDestructors in m.config.globalOptions and t.skipTypes(abstractInst).kind == tySequence:
       seqV2ContentType(m, t, check)
     else:
@@ -1255,7 +1167,7 @@ proc genMemberProcHeader(m: BModule; prc: PSym; result: var Builder; asPtr: bool
   let isCtor = sfConstructor in prc.flags
   var check = initIntSet()
   fillBackendName(m, prc)
-  backendEnsureMutable prc
+  ensureMutable prc
   fillLoc(prc.locImpl, locProc, prc.ast[namePos], OnUnknown)
   var memberOp = "#." #only virtual
   var typ: PType
@@ -1328,9 +1240,7 @@ proc genProcHeader(m: BModule; prc: PSym; result: var Builder; visibility: var D
     elif prc.typ.callConv == ccInline or isNonReloadable(m, prc):
       visibility = StaticProc
     elif sfImportc notin prc.flags:
-      if not isSharedInstanceCName(m, prc):
-        visibility = Private
-      # else: plain extern — the definition is shared across TUs
+      visibility = Private
     if asPtr:
       result.addProcVar(m, prc, name, params, rettype, isStatic = isStaticVar, ignoreAttributes = true)
     else:
@@ -1410,8 +1320,6 @@ proc genTypeInfoAuxBase(m: BModule; typ, origType: PType;
   else:
     m.s[cfsStrData].addDeclWithVisibility(Private):
       m.s[cfsStrData].addVar(kind = Local, name = name, typ = "TNimType")
-    if m.config.cmd == cmdNifC:
-      m.icDataDefs.add (name, icNifName(m, origType))
 
 proc genTypeInfoAux(m: BModule; typ, origType: PType, name: Rope;
                     info: TLineInfo) =
@@ -1558,38 +1466,27 @@ proc genObjectInfo(m: BModule; typ, origType: PType, name: Rope; info: TLineInfo
     t.incl tfObjHasKids
     t = t.baseClass
 
-proc validTupleTypeFields(t: PType): int =
-  # we want to treat tuples with only void fields as empty, so we need to exclude void types here:
-  result = 0
-  for a in t.kids:
-    if not isEmptyType(a): inc result
-
 proc genTupleInfo(m: BModule; typ, origType: PType, name: Rope; info: TLineInfo) =
   genTypeInfoAuxBase(m, typ, typ, name, cIntValue(0), info)
   var expr = getNimNode(m)
-  let nonVoidKids = validTupleTypeFields(typ)
-  if nonVoidKids > 0:
-    var tmp = getTempName(m) & "_" & $nonVoidKids
-    genTNimNodeArray(m, tmp, nonVoidKids)
-    var j = 0
+  if not typ.isEmptyTupleType:
+    var tmp = getTempName(m) & "_" & $typ.kidsLen
+    genTNimNodeArray(m, tmp, typ.kidsLen)
     for i, a in typ.ikids:
-      # Do not produce code for void types
-      if isEmptyType(a): continue
       var tmp2 = getNimNode(m)
       let fieldTypInfo = genTypeInfoV1(m, a, info)
-      m.s[cfsTypeInit3].addSubscriptAssignment(tmp, cIntValue(j), cAddr(tmp2))
+      m.s[cfsTypeInit3].addSubscriptAssignment(tmp, cIntValue(i), cAddr(tmp2))
       m.s[cfsTypeInit3].addFieldAssignment(tmp2, "kind", 1)
       m.s[cfsTypeInit3].addFieldAssignmentWithValue(tmp2, "offset"):
         m.s[cfsTypeInit3].addOffsetof(getTypeDesc(m, origType, dkVar), "Field" & $i)
       m.s[cfsTypeInit3].addFieldAssignment(tmp2, "typ", fieldTypInfo)
       m.s[cfsTypeInit3].addFieldAssignment(tmp2, "name", "\"Field" & $i & "\"")
-      inc j
-    m.s[cfsTypeInit3].addFieldAssignment(expr, "len", nonVoidKids)
+    m.s[cfsTypeInit3].addFieldAssignment(expr, "len", typ.kidsLen)
     m.s[cfsTypeInit3].addFieldAssignment(expr, "kind", 2)
     m.s[cfsTypeInit3].addFieldAssignment(expr, "sons",
       cAddr(subscript(tmp, cIntValue(0))))
   else:
-    m.s[cfsTypeInit3].addFieldAssignment(expr, "len", cIntValue(0))
+    m.s[cfsTypeInit3].addFieldAssignment(expr, "len", typ.kidsLen)
     m.s[cfsTypeInit3].addFieldAssignment(expr, "kind", 2)
   m.s[cfsTypeInit3].addFieldAssignment(tiNameForHcr(m, name), "node", cAddr(expr))
 
@@ -1699,13 +1596,8 @@ proc declareNimType(m: BModule; name: string; str: Rope, module: int) =
           m.s[cfsTypeInit1].addArgument(hcrGlobal):
             m.s[cfsTypeInit1].add("\"" & str & "\"")
   else:
-    # cnif-mark the name: this extern declaration is the reference the
-    # def-retention check consults when the defining TU regenerates and
-    # the typeinfo cannot be re-demanded (type vanished) — the referencing
-    # TU must lose its reuse then instead of producing a link error
-    let declName = if m.config.cmd == cmdNifC: markCName(str) else: str
     m.s[cfsStrData].addDeclWithVisibility(Extern):
-      m.s[cfsStrData].addVar(kind = Local, name = declName, typ = nr)
+      m.s[cfsStrData].addVar(kind = Local, name = str, typ = nr)
 
 proc genTypeInfo2Name(m: BModule; t: PType): Rope =
   var it = t
@@ -1794,7 +1686,7 @@ proc genHook(m: BModule; t: PType; info: TLineInfo; op: TTypeAttachedOp; result:
         echo "ayclic but has this =trace ", t, " ", theProc.ast
   else:
     when false:
-      if op == attachedTrace and m.config.selectedGC in {gcOrc, gcYrc} and
+      if op == attachedTrace and m.config.selectedGC == gcOrc and
           containsGarbageCollectedRef(t):
         # unfortunately this check is wrong for an object type that only contains
         # .cursor fields like 'Node' inside 'cycleleak'.
@@ -1844,8 +1736,6 @@ proc genTypeInfoV2OldImpl(m: BModule; t, origType: PType, name: Rope; info: TLin
   cgsym(m, "TNimTypeV2")
   m.s[cfsStrData].addDeclWithVisibility(Private):
     m.s[cfsStrData].addVar(kind = Local, name = name, typ = "TNimTypeV2")
-  if m.config.cmd == cmdNifC:
-    m.icDataDefs.add (name, icNifName(m, origType))
 
   var flags = 0
   if not canFormAcycle(m.g.graph, t): flags = flags or 1
@@ -1908,15 +1798,8 @@ proc genTypeInfoV2OldImpl(m: BModule; t, origType: PType, name: Rope; info: TLin
 
 proc genTypeInfoV2Impl(m: BModule; t, origType: PType, name: Rope; info: TLineInfo) =
   cgsym(m, "TNimTypeV2")
-  # Under `nim nifc` every `cg` process that demands this type's RTTI emits its
-  # definition (emit-everywhere). The forward declaration must therefore be a
-  # real `extern` (not a tentative definition) so a TU whose copy the merge
-  # stage drops still only *declares* it; the definition itself is wrapped as a
-  # droppable `'d'` unit below and assigned to a single owner.
-  m.s[cfsStrData].addDeclWithVisibility(if m.config.cmd == cmdNifC: Extern else: Private):
+  m.s[cfsStrData].addDeclWithVisibility(Private):
     m.s[cfsStrData].addVar(kind = Local, name = name, typ = "TNimTypeV2")
-  if m.config.cmd == cmdNifC:
-    m.icDataDefs.add (name, icNifName(m, origType))
 
   var flags = 0
   if not canFormAcycle(m.g.graph, t): flags = flags or 1
@@ -1977,12 +1860,7 @@ proc genTypeInfoV2Impl(m: BModule; t, origType: PType, name: Rope; info: TLineIn
         else:
           typeEntry.addField(typeInit, name = "flags"):
             typeEntry.addIntValue(flags)
-  if m.config.cmd == cmdNifC:
-    m.s[cfsVars].add(cnifDefDirective(name, "d", icNifName(m, origType)))
-    m.s[cfsVars].add extract(typeEntry)
-    m.s[cfsVars].add(cnifEndDefs())
-  else:
-    m.s[cfsVars].add extract(typeEntry)
+  m.s[cfsVars].add extract(typeEntry)
 
   if t.kind == tyObject and t.baseClass != nil and optEnableDeepCopy in m.config.globalOptions:
     discard genTypeInfoV1(m, t, info)
@@ -2021,13 +1899,7 @@ proc genTypeInfoV2(m: BModule; t: PType; info: TLineInfo): Rope =
   m.typeInfoMarkerV2[sig] = result
 
   let owner = t.skipTypes(typedescPtrs).itemId.module
-  # In the per-module backend (`cg`) RTTI is emit-everywhere like procs and
-  # consts: every demanding module emits the `'d'` definition (deduped to one
-  # owner by the merge stage). The owner-routing below would instead push the
-  # definition into the owner module's *unwritten* backend module (discarded in
-  # this process) and emit only an extern here, leaving the symbol undefined.
-  let perModuleCg = m.config.cmd == cmdNifC and m.config.icBackendStage == "cg"
-  if not perModuleCg and owner != m.module.position and myModuleOpenForCodegen(m, FileIndex owner):
+  if owner != m.module.position and myModuleOpenForCodegen(m, FileIndex owner):
     # make sure the type info is created in the owner module
     discard genTypeInfoV2(m.g.mods[owner], origType, info)
     # reference the type info as extern here
@@ -2094,10 +1966,6 @@ proc genTypeInfoV1(m: BModule; t: PType; info: TLineInfo): Rope =
 
   let marker = m.g.typeInfoMarker.getOrDefault(sig)
   if marker.str != "":
-    when defined(icDbgRefc):
-      if "catchableerror" in marker.str:
-        echo "[icNti] ", marker.str, " in mod=", m.module.name.s,
-          " -> extern:globalMarker owner=", marker.owner
     cgsym(m, "TNimType")
     cgsym(m, "TNimNode")
     declareNimType(m, "TNimType", marker.str, marker.owner)
@@ -2108,16 +1976,8 @@ proc genTypeInfoV1(m: BModule; t: PType; info: TLineInfo): Rope =
   result = "NTI$1$2_" % [rope(typeToC(t)), rope($sig)]
   m.typeInfoMarker[sig] = result
 
-  when defined(icDbgRefc):
-    template dbgNti(branch: string) =
-      if "catchableerror" in result:
-        echo "[icNti] ", result, " in mod=", m.module.name.s, " -> ", branch
-  else:
-    template dbgNti(branch: string) = discard
-
   let old = m.g.graph.emittedTypeInfo.getOrDefault($result)
   if old != FileIndex(0):
-    dbgNti "extern:emittedTypeInfo"
     cgsym(m, "TNimType")
     cgsym(m, "TNimNode")
     declareNimType(m, "TNimType", result, old.int)
@@ -2125,7 +1985,6 @@ proc genTypeInfoV1(m: BModule; t: PType; info: TLineInfo): Rope =
 
   var owner = t.skipTypes(typedescPtrs).itemId.module
   if owner != m.module.position and myModuleOpenForCodegen(m, FileIndex owner):
-    dbgNti "extern:ownerRouted"
     # make sure the type info is created in the owner module
     discard genTypeInfoV1(m.g.mods[owner], origType, info)
     # reference the type info as extern here
@@ -2136,9 +1995,8 @@ proc genTypeInfoV1(m: BModule; t: PType; info: TLineInfo): Rope =
   else:
     owner = m.module.position.int32
 
-  dbgNti "DEFINED-HERE"
   m.g.typeInfoMarker[sig] = (str: result, owner: owner)
-  #rememberEmittedTypeInfo(m.g.graph, FileIndex(owner), $result)
+  rememberEmittedTypeInfo(m.g.graph, FileIndex(owner), $result)
 
   case t.kind
   of tyEmpty, tyVoid: result = cIntValue(0)

compiler/ccgutils.nim

@@ -112,13 +112,10 @@ proc encodeName*(name: string): string =
 
 proc makeUnique(m: BModule; s: PSym, name: string = ""): string =
   result = if name == "": s.name.s else: name
-  # keep backend-minted ids out of the `_u` namespace; their item counter
-  # restarts at 0 and would collide with loaded symbols' ids
-  result.add(if s.itemId.isBackendMinted: "_c" else: "_u")
-  result.add $s.itemId.item
-  # module suffix LAST (a strippable trailing token; see `mangleProcNameExt`)
   result.add "__"
   result.add m.g.graph.ifaces[s.itemId.module].uniqueName
+  result.add "_u"
+  result.add $s.itemId.item
 
 proc encodeSym*(m: BModule; s: PSym; makeUnique: bool = false; extra: string = ""): string =
   #Module::Type

compiler/cgen.nim

@@ -19,10 +19,6 @@ import
   mangleutils, cbuilderbase, modulegraphs
 
 from expanddefaults import caseObjDefaultBranch
-from ast2nif import globalName, toNifFilename, icNifTypeName
-from typekeys import modname
-from std/algorithm import sort
-import cnif
 
 import pipelineutils
 
@@ -34,6 +30,7 @@ when not defined(leanCompiler):
 
 import std/strutils except `%`, addf # collides with ropes.`%`
 
+from ic / ic import ModuleBackendFlag
 import std/[dynlib, math, tables, sets, os, intsets, hashes]
 
 const
@@ -55,7 +52,7 @@ when not declared(dynlib.libCandidates):
     else:
       dest.add(s)
 
-when defined(tinyc): # == hasTinyCBackend; spelled out for the IC dep scanner
+when options.hasTinyCBackend:
   import tccgen
 
 proc hcrOn(m: BModule): bool = m.config.hcrOn
@@ -65,18 +62,9 @@ proc addForwardedProc(m: BModule, prc: PSym) =
   m.g.forwardedProcs.add(prc)
 
 proc newModule*(g: BModuleList; module: PSym; conf: ConfigRef; idgen: IdGenerator): BModule
-proc getCFile*(m: BModule): AbsoluteFile
 
 proc findPendingModule(m: BModule, s: PSym): BModule =
   # TODO fixme
-  if m.config.cmd == cmdNifC and m.config.icBackendStage == "cg":
-    # Per-module backend codegen: only module M (`m`) is emitted in this
-    # process, so every demanded definition — whether a normal proc owned by
-    # another (here unwritten) module or a minted instance/hook — is emitted
-    # into M's TU. Definitions owned elsewhere are emitted again by their own
-    # module's cg process; the merge stage keeps one per C name and turns the
-    # rest into prototypes (which already live in the unmarked protos section).
-    return m
   if m.config.symbolFiles == v2Sf or optCompress in m.config.globalOptions:
     let ms = s.itemId.module  #getModule(s)
     result = m.g.mods[ms]
@@ -84,52 +72,15 @@ proc findPendingModule(m: BModule, s: PSym): BModule =
     var ms = getModule(s)
     registerModule m.g.graph, ms
     if ms.position >= m.g.mods.len:
-      result = newModule(m.g, ms, m.config, idGeneratorForBackend(ms))
+      result = newModule(m.g, ms, m.config, idGeneratorFromModule(ms))
     else:
       result = m.g.mods[ms.position]
       if result == nil:
-        result = newModule(m.g, ms, m.config, idGeneratorForBackend(ms))
+        result = newModule(m.g, ms, m.config, idGeneratorFromModule(ms))
   else:
     var ms = getModule(s)
     result = m.g.mods[ms.position]
 
-proc icNifName(m: BModule; s: PSym): string =
-  ## The serialized NIF name of `s`, recorded next to its C name in the cnif
-  ## artifact so a later run can re-demand the definition when a reused TU
-  ## still references it (the def-retention check). Backend-minted symbols
-  ## have no NIF name.
-  if m.config.cmd == cmdNifC and s != nil and not isBackendMinted(s.itemId):
-    result = globalName(s, m.config)
-  else:
-    result = ""
-
-proc icNifName(m: BModule; t: PType): string =
-  ## The type flavor: recorded next to RTTI data definitions so the
-  ## def-retention check can re-demand the typeinfo of a regenerating TU's
-  ## previous artifact (`genTypeInfo` is type-driven, not symbol-driven).
-  if m.config.cmd == cmdNifC:
-    result = icNifTypeName(t, m.config)
-  else:
-    result = ""
-
-
-proc emitsBodyInThisModule(m: BModule, prc: PSym): bool =
-  ## Per-module backend codegen is concerned with ONE module: it emits the
-  ## bodies of the routines that module OWNS (its own top-level defs) and only
-  ## *prototypes* a routine owned by another module — that routine's body is
-  ## emitted by its own module's `cg` process, and the merge stage's DCE prunes
-  ## whatever ends up globally dead. The funnel where the main module re-emitted
-  ## its entire transitive closure (≈1.8 GB, a 56 MB `.c.nif`) is exactly this
-  ## rule being absent.
-  ##
-  ## Generic instances and synthesized hooks (`=destroy`, `$`, …) have no single
-  ## owning-module top-level — they are minted on demand — so each demander emits
-  ## them and the merge stage deduplicates by their content-addressed C name.
-  if not (m.config.cmd == cmdNifC and m.config.icBackendStage == "cg"):
-    return true
-  result = prc.itemId.module == m.module.position or
-           (prc.disamb and (InstanceDisambBit or HookDisambBit)) != 0'i32
-
 proc initLoc(k: TLocKind, lode: PNode, s: TStorageLoc, flags: TLocFlags = {}): TLoc =
   result = TLoc(k: k, storage: s, lode: lode,
                 snippet: "", flags: flags)
@@ -174,6 +125,8 @@ proc useHeader(m: BModule, sym: PSym) =
 proc cgsym(m: BModule, name: string)
 proc cgsymValue(m: BModule, name: string): Rope
 
+proc getCFile(m: BModule): AbsoluteFile
+
 proc getModuleDllPath(m: BModule): Rope =
   let (dir, name, ext) = splitFile(getCFile(m))
   let filename = strutils.`%`(platform.OS[m.g.config.target.targetOS].dllFrmt, [name & ext])
@@ -437,11 +390,7 @@ proc lenField(p: BProc, val: Rope): Rope {.inline.} =
 
 proc lenExpr(p: BProc; a: TLoc): Rope =
   if optSeqDestructors in p.config.globalOptions:
-    if p.config.usesSso() and a.lode != nil and a.t != nil and
-        a.t.skipTypes(abstractInst).kind == tyString:
-      result = cCall(cgsymValue(p.module, "nimStrLen"), rdLoc(a))
-    else:
-      result = dotField(rdLoc(a), "len")
+    result = dotField(rdLoc(a), "len")
   else:
     let ra = rdLoc(a)
     result = cIfExpr(ra, lenField(p, ra), cIntValue(0))
@@ -582,15 +531,7 @@ proc resetLoc(p: BProc, loc: var TLoc) =
 
     let atyp = skipTypes(loc.t, abstractInst)
     let rl = rdLoc(loc)
-    if typ.kind == tyString and p.config.usesSso():
-      # SmallString zero state: bytes=0 (slen=0 in low byte, all inline chars zeroed)
-      if atyp.kind in {tyVar, tyLent}:
-        p.s(cpsStmts).addAssignment(derefField(rl, "bytes"), cIntValue(0))
-        p.s(cpsStmts).addAssignment(derefField(rl, "more"), NimNil)
-      else:
-        p.s(cpsStmts).addAssignment(dotField(rl, "bytes"), cIntValue(0))
-        p.s(cpsStmts).addAssignment(dotField(rl, "more"), NimNil)
-    elif atyp.kind in {tyVar, tyLent}:
+    if atyp.kind in {tyVar, tyLent}:
       p.s(cpsStmts).addAssignment(derefField(rl, "len"), cIntValue(0))
       p.s(cpsStmts).addAssignment(derefField(rl, "p"), NimNil)
     else:
@@ -640,13 +581,8 @@ proc constructLoc(p: BProc, loc: var TLoc, isTemp = false) =
   let typ = loc.t
   if optSeqDestructors in p.config.globalOptions and skipTypes(typ, abstractInst + {tyStatic}).kind in {tyString, tySequence}:
     let rl = rdLoc(loc)
-    if skipTypes(typ, abstractInst + {tyStatic}).kind == tyString and p.config.usesSso():
-      # SmallString zero state: bytes=0 (slen=0 in low byte, all inline chars zeroed)
-      p.s(cpsStmts).addFieldAssignment(rl, "bytes", cIntValue(0))
-      p.s(cpsStmts).addFieldAssignment(rl, "more", NimNil)
-    else:
-      p.s(cpsStmts).addFieldAssignment(rl, "len", cIntValue(0))
-      p.s(cpsStmts).addFieldAssignment(rl, "p", NimNil)
+    p.s(cpsStmts).addFieldAssignment(rl, "len", cIntValue(0))
+    p.s(cpsStmts).addFieldAssignment(rl, "p", NimNil)
   elif not isComplexValueType(typ):
     if containsGarbageCollectedRef(loc.t):
       var nilLoc: TLoc = initLoc(locTemp, loc.lode, OnStack)
@@ -804,9 +740,6 @@ proc assignGlobalVar(p: BProc, n: PNode; value: Rope) =
   useHeader(p.module, s)
   if lfNoDecl in s.loc.flags: return
   if not containsOrIncl(p.module.declaredThings, s.id):
-    if p.config.cmd == cmdNifC and sfImportc notin s.flags:
-      p.module.icDataDefs.add (stripCnifMarks(s.loc.snippet),
-                               icNifName(p.module, s))
     if sfThread in s.flags:
       declareThreadVar(p.module, s, sfImportc in s.flags)
       if value != "":
@@ -1367,34 +1300,6 @@ proc genProcBody(p: BProc; procBody: PNode) =
       p.blocks[0].sections[cpsInit].addCall(cgsymValue(p.module, "nimErrorFlag"))
 
 proc genProcLvl3*(m: BModule, prc: PSym) =
-  if m.config.cmd == cmdNifC:
-    fillBackendName(m, prc)
-    if (prc.disamb and (InstanceDisambBit or HookDisambBit)) != 0'i32 and
-        containsOrIncl(m.emittedContentDefs, stripCnifMarks(prc.loc.snippet)):
-      # A different symbol already emitted a body under this content-addressed
-      # C name in this TU (same generic instance / hook minted in two source
-      # modules, both loaded here). Emitting a second body is a C redefinition;
-      # a prototype was already produced for it, so just stop.
-      return
-    if sfDispatcher in prc.flags and sfMainModule notin m.module.flags:
-      # A method dispatcher enumerates the whole program's method set: its
-      # body is synthesized by `generateIfMethodDispatchers` only after all
-      # modules have been generated, and its single definition is emitted
-      # into the main TU by `finishModule` (main is finished last and never
-      # reused, so the definition can never go stale inside a cached TU).
-      # Any demand before that point yields a prototype.
-      genProcPrototype(m, prc)
-      return
-    if prc.itemId.module != m.module.position and
-        not isBackendMinted(prc.itemId) and
-        (prc.typ == nil or prc.typ.callConv != ccInline) and
-        sfDispatcher notin prc.flags:
-      # this TU embeds a definition whose body lives in another module's
-      # NIF: record the impl dependency (the artifact's cdeps head) so the
-      # reuse gate re-checks that module's impl cookie. Inline bodies are
-      # already part of the iface cookie; dispatcher bodies are synthesized
-      # from the whole program and live in main, which never reuses.
-      m.icImplMods.incl prc.itemId.module
   var p = newProc(prc, m)
   var header = newBuilder("")
   let isCppMember = m.config.backend == backendCpp and sfCppMember * prc.flags != {}
@@ -1428,7 +1333,7 @@ proc genProcLvl3*(m: BModule, prc: PSym) =
         # declare the result symbol:
         assignLocalVar(p, resNode)
         assert(res.loc.snippet != "")
-        if p.config.selectedGC in {gcArc, gcAtomicArc, gcOrc, gcYrc} and
+        if p.config.selectedGC in {gcArc, gcAtomicArc, gcOrc} and
             allPathsAsgnResult(p, procBody) == InitSkippable:
           # In an ideal world the codegen could rely on injectdestructors doing its job properly
           # and then the analysis step would not be required.
@@ -1515,37 +1420,7 @@ proc genProcLvl3*(m: BModule, prc: PSym) =
           generatedProc.add(extract(p.s(cpsStmts)))
         if optStackTrace in prc.options: generatedProc.add(deinitFrame(p))
         generatedProc.add(returnStmt)
-  if m.config.cmd == cmdNifC:
-    # definition directive for the cnif artifact: groups the proc's text
-    # under its name and carries the root-relevant flags. The end directive
-    # right after the text makes the definition self-delimiting, so raw
-    # cfsProcs emitters (NimMain block, trav markers, ...) never end up
-    # inside a definition's span.
-    var defFlags = ""
-    if sfExportc in prc.flags or sfConstructor in prc.flags: defFlags.add 'x'
-    if sfCompilerProc in prc.flags: defFlags.add 'c'
-    if prc.kind == skMethod or sfDispatcher in prc.flags: defFlags.add 'm'
-    if (prc.typ == nil or prc.typ.callConv != ccInline) and
-        sfDispatcher notin prc.flags:
-      # A unique program-wide definition: external linkage, so exactly one
-      # translation unit may embed its body and everyone else declares it.
-      # Each module's `cg` process emits the body (emit-everywhere); this flag
-      # tells the merge stage which definitions to assign a single owner and
-      # prototype in the rest. The complement — inline procs and method
-      # dispatchers — is emitted into every using TU (`static`/main-only) and
-      # must never be deduplicated.
-      defFlags.add 'u'
-    if not hasCnifMarks(prc.loc.snippet):
-      # The C name was not minted through `fillBackendName` (e.g. set by an
-      # `extern`/`rtl` pragma at sem time), so its uses are invisible to the
-      # artifact's liveness walk — conservatively keep the definition.
-      defFlags.add 'x'
-    m.s[cfsProcs].add(cnifDefDirective(stripCnifMarks(prc.loc.snippet), defFlags,
-                                       icNifName(m, prc)))
-    m.s[cfsProcs].add(extract(generatedProc))
-    m.s[cfsProcs].add(cnifEndDefs())
-  else:
-    m.s[cfsProcs].add(extract(generatedProc))
+  m.s[cfsProcs].add(extract(generatedProc))
   if isReloadable(m, prc):
     m.s[cfsDynLibInit].add('\t')
     m.s[cfsDynLibInit].addAssignmentWithValue(prc.loc.snippet):
@@ -1591,15 +1466,10 @@ proc genProcPrototype(m: BModule, sym: PSym) =
     var header = newBuilder("")
     var visibility: DeclVisibility = None
     genProcHeader(m, sym, header, visibility, asPtr = asPtr, addAttributes = true)
-    # A prototype is not a *use*: strip the cnif name marks so the artifact's
-    # liveness walk does not see every forward-declared proc as referenced.
-    var headerText = extract(header)
-    if m.config.cmd == cmdNifC:
-      headerText = stripCnifMarks(headerText)
     if asPtr:
       m.s[cfsProcHeaders].addDeclWithVisibility(visibility):
         # genProcHeader would give variable declaration, add it directly
-        m.s[cfsProcHeaders].add(headerText)
+        m.s[cfsProcHeaders].add(extract(header))
     else:
       let extraVis =
         if sym.typ.callConv != ccInline and requiresExternC(m, sym):
@@ -1608,7 +1478,7 @@ proc genProcPrototype(m: BModule, sym: PSym) =
           None
       m.s[cfsProcHeaders].addDeclWithVisibility(extraVis):
         m.s[cfsProcHeaders].addDeclWithVisibility(visibility):
-          m.s[cfsProcHeaders].add(headerText)
+          m.s[cfsProcHeaders].add(extract(header))
           m.s[cfsProcHeaders].finishProcHeaderAsProto()
 
 include inliner
@@ -1686,8 +1556,7 @@ proc genProcLvl2(m: BModule, prc: PSym) =
       # which will actually become a function pointer
       if isReloadable(m, prc):
         genProcPrototype(q, prc)
-      if emitsBodyInThisModule(m, prc):
-        genProcLvl3(q, prc)
+      genProcLvl3(q, prc)
   else:
     fillProcLoc(m, prc.ast[namePos])
     useHeader(m, prc)
@@ -1697,7 +1566,7 @@ proc requestConstImpl(p: BProc, sym: PSym) =
   if genConstSetup(p, sym):
     let m = p.module
     # declare implementation:
-    let q = findPendingModule(m, sym)
+    var q = findPendingModule(m, sym)
     if q != nil and not containsOrIncl(q.declaredThings, sym.id):
       assert q.initProc.module == q
       genConstDefinition(q, p, sym)
@@ -1721,12 +1590,6 @@ proc genProc(m: BModule, prc: PSym) =
         if not containsOrIncl(m.g.generatedHeader.declaredThings, prc.id):
           genProcLvl3(m.g.generatedHeader, prc)
 
-proc requestProcDef*(m: BModule, prc: PSym) =
-  ## Public demand entry: request `prc`'s definition; it is routed to the
-  ## module that owns it and generated once, exactly as if some generated
-  ## code had referenced it.
-  genProc(m, prc)
-
 proc genVarPrototype(m: BModule, n: PNode) =
   #assert(sfGlobal in sym.flags)
   let sym = n.sym
@@ -1796,7 +1659,7 @@ proc getSomeNameForModule(conf: ConfigRef, filename: AbsoluteFile): Rope =
   ## Returns a mangled module name.
   result = mangleModuleName(conf, filename).mangle
 
-proc getSomeNameForModule*(m: BModule): Rope =
+proc getSomeNameForModule(m: BModule): Rope =
   ## Returns a mangled module name.
   assert m.module.kind == skModule
   assert m.module.owner.kind == skPackage
@@ -1825,7 +1688,7 @@ proc hcrGetProcLoadCode(builder: var Builder, m: BModule, sym, prefix, handle, g
 # prevents inlining of the NimMainInner function and dependent
 # functions, which might otherwise merge their stack frames.
 proc isInnerMainVolatile(m: BModule): bool =
-  m.config.selectedGC notin {gcNone, gcArc, gcAtomicArc, gcOrc, gcYrc}
+  m.config.selectedGC notin {gcNone, gcArc, gcAtomicArc, gcOrc}
 
 proc genPreMain(m: BModule) =
   m.s[cfsProcs].addDeclWithVisibility(Private):
@@ -1837,6 +1700,8 @@ proc genPreMain(m: BModule) =
       m.s[cfsProcs].addVar(name = "cmdCount", typ = CInt)
     m.s[cfsProcs].addDeclWithVisibility(Private):
       m.s[cfsProcs].addVar(name = "cmdLine", typ = ptrType(ptrType(CChar)))
+    m.s[cfsProcs].addDeclWithVisibility(Private):
+      m.s[cfsProcs].addVar(name = "gEnv", typ = ptrType(ptrType(CChar)))
   m.s[cfsProcs].addDeclWithVisibility(Private):
     m.s[cfsProcs].addProcHeader(m.config.nimMainPrefix & "PreMain", CVoid, cProcParams())
     m.s[cfsProcs].finishProcHeaderWithBody():
@@ -1870,7 +1735,7 @@ proc genNimMainInner(m: BModule) =
   m.s[cfsProcs].addNewline()
 
 proc initStackBottom(m: BModule): bool =
-  not (m.config.target.targetOS == osStandalone or m.config.selectedGC in {gcNone, gcArc, gcAtomicArc, gcOrc, gcYrc})
+  not (m.config.target.targetOS == osStandalone or m.config.selectedGC in {gcNone, gcArc, gcAtomicArc, gcOrc})
 
 proc genNimMainProc(m: BModule, preMainCode: Snippet) =
   m.s[cfsProcs].addProcHeader(ccCDecl, m.config.nimMainPrefix & "NimMain", CVoid, cProcParams())
@@ -1897,10 +1762,12 @@ proc genNimMainBody(m: BModule, preMainCode: Snippet) =
 proc genPosixCMain(m: BModule) =
   m.s[cfsProcs].addProcHeader("main", CInt, cProcParams(
     (name: "argc", typ: CInt),
-    (name: "args", typ: ptrType(ptrType(CChar)))))
+    (name: "args", typ: ptrType(ptrType(CChar))),
+    (name: "env", typ: ptrType(ptrType(CChar)))))
   m.s[cfsProcs].finishProcHeaderWithBody():
     m.s[cfsProcs].addAssignment("cmdLine", "args")
     m.s[cfsProcs].addAssignment("cmdCount", "argc")
+    m.s[cfsProcs].addAssignment("gEnv", "env")
     genMainProcsWithResult(m)
   m.s[cfsProcs].addNewline()
 
@@ -1998,7 +1865,7 @@ proc genMainProc(m: BModule) =
         builder.addCallStmt(cgsymValue(m, "nimLoadLibraryError"), strLit)
 
     loadLib(preMainBuilder, "hcr_handle", "hcrGetProc")
-    if m.config.selectedGC in {gcArc, gcAtomicArc, gcOrc, gcYrc}:
+    if m.config.selectedGC in {gcArc, gcAtomicArc, gcOrc}:
       preMainBuilder.addCallStmt(m.config.nimMainPrefix & "PreMain")
     else:
       preMainBuilder.addVar(name = "rtl_handle", typ = CPointer)
@@ -2059,6 +1926,36 @@ proc genMainProc(m: BModule) =
     if m.config.cppCustomNamespace.len > 0:
       openNamespaceNim(m.config.cppCustomNamespace, m.s[cfsProcs])
 
+proc registerInitProcs*(g: BModuleList; m: PSym; flags: set[ModuleBackendFlag]) =
+  ## Called from the IC backend.
+  if HasDatInitProc in flags:
+    let datInit = getSomeNameForModule(g.config, g.config.toFullPath(m.info.fileIndex).AbsoluteFile) & "DatInit000"
+    g.mainModProcs.addDeclWithVisibility(Private):
+      g.mainModProcs.addProcHeader(ccNimCall, datInit, CVoid, cProcParams())
+      g.mainModProcs.finishProcHeaderAsProto()
+    g.mainDatInit.addCallStmt(datInit)
+  if HasModuleInitProc in flags:
+    let init = getSomeNameForModule(g.config, g.config.toFullPath(m.info.fileIndex).AbsoluteFile) & "Init000"
+    g.mainModProcs.addDeclWithVisibility(Private):
+      g.mainModProcs.addProcHeader(ccNimCall, init, CVoid, cProcParams())
+      g.mainModProcs.finishProcHeaderAsProto()
+    if sfMainModule in m.flags:
+      g.mainModInit.addCallStmt(init)
+    elif sfSystemModule in m.flags:
+      g.mainDatInit.addCallStmt(init) # systemInit must called right after systemDatInit if any
+    else:
+      g.otherModsInit.addCallStmt(init)
+
+proc whichInitProcs*(m: BModule): set[ModuleBackendFlag] =
+  # called from IC.
+  result = {}
+  if m.hcrOn or m.preInitProc.s(cpsInit).buf.len > 0 or m.preInitProc.s(cpsStmts).buf.len > 0:
+    result.incl HasModuleInitProc
+  for i in cfsTypeInit1..cfsDynLibInit:
+    if m.s[i].buf.len != 0:
+      result.incl HasDatInitProc
+      break
+
 proc registerModuleToMain(g: BModuleList; m: BModule) =
   let
     init = m.getInitName
@@ -2168,7 +2065,7 @@ proc registerModuleToMain(g: BModuleList; m: BModule) =
   if sfSystemModule in m.module.flags:
     if emulatedThreadVars(m.config) and m.config.target.targetOS != osStandalone:
       g.mainDatInit.addCallStmt(cgsymValue(m, "initThreadVarsEmulation"))
-    if m.config.target.targetOS != osStandalone and m.config.selectedGC notin {gcNone, gcArc, gcAtomicArc, gcOrc, gcYrc}:
+    if m.config.target.targetOS != osStandalone and m.config.selectedGC notin {gcNone, gcArc, gcAtomicArc, gcOrc}:
       g.mainDatInit.addCallStmt(cgsymValue(m, "initStackBottomWith"),
         cCast(CPointer, cAddr("inner")))
 
@@ -2183,40 +2080,6 @@ proc registerModuleToMain(g: BModuleList; m: BModule) =
     else:
       g.otherModsInit.addCallStmt(init)
 
-proc registerReusedModuleToMain*(g: BModuleList; m: BModule;
-                                initRequired, datInitRequired: bool) =
-  ## `registerModuleToMain` for a module whose cached translation unit is
-  ## reused: the init/datInit presence comes from the artifact's meta head
-  ## instead of the (never generated) sections. Mirrors the non-hcr path of
-  ## `registerModuleToMain` — reuse is disabled when hcr is on.
-  let
-    init = m.getInitName
-    datInit = m.getDatInitName
-
-  if datInitRequired:
-    g.mainModProcs.addDeclWithVisibility(Private):
-      g.mainModProcs.addProcHeader(ccNimCall, datInit, CVoid, cProcParams())
-      g.mainModProcs.finishProcHeaderAsProto()
-    g.mainDatInit.addCallStmt(datInit)
-
-  if sfSystemModule in m.module.flags:
-    if emulatedThreadVars(m.config) and m.config.target.targetOS != osStandalone:
-      g.mainDatInit.addCallStmt(cgsymValue(m, "initThreadVarsEmulation"))
-    if m.config.target.targetOS != osStandalone and m.config.selectedGC notin {gcNone, gcArc, gcAtomicArc, gcOrc, gcYrc}:
-      g.mainDatInit.addCallStmt(cgsymValue(m, "initStackBottomWith"),
-        cCast(CPointer, cAddr("inner")))
-
-  if initRequired:
-    g.mainModProcs.addDeclWithVisibility(Private):
-      g.mainModProcs.addProcHeader(ccNimCall, init, CVoid, cProcParams())
-      g.mainModProcs.finishProcHeaderAsProto()
-    if sfMainModule in m.module.flags:
-      g.mainModInit.addCallStmt(init)
-    elif sfSystemModule in m.module.flags:
-      g.mainDatInit.addCallStmt(init) # systemInit right after systemDatInit
-    else:
-      g.otherModsInit.addCallStmt(init)
-
 proc genDatInitCode(m: BModule) =
   ## this function is called in cgenWriteModules after all modules are closed,
   ## it means raising dependency on the symbols is too late as it will not propagate
@@ -2464,16 +2327,6 @@ proc genModule(m: BModule, cfile: Cfile): Rope =
       moduleIsEmpty = false
       res.add(extract(m.s[i]))
 
-  # what `registerModuleToMain` will announce for this module; recorded in
-  # the artifact's meta head so a later run can reuse the TU
-  let initRequired = m.s[cfsInitProc].buf.len > 0
-  let datInitRequired = m.s[cfsDatInitProc].buf.len > 0
-
-  if m.config.cmd == cmdNifC:
-    # close the definitions section: the init procs that follow belong to
-    # the artifact's top level (always-run code, hence liveness roots)
-    res.add(cnifEndDefs())
-
   if m.s[cfsInitProc].buf.len > 0:
     moduleIsEmpty = false
     res.add(extract(m.s[cfsInitProc]))
@@ -2496,22 +2349,6 @@ proc genModule(m: BModule, cfile: Cfile): Rope =
 
   postprocessCode(m.config, result)
 
-  if m.config.cmd == cmdNifC and result.len > 0:
-    let artifact = cfile.cname.string & ".nif"
-    var implDeps: seq[string] = @[]
-    for pos in m.icImplMods.items:
-      if pos != m.module.position:
-        implDeps.add modname(pos, m.config)
-    sort implDeps
-    writeCnifArtifact(result, artifact, initRequired, datInitRequired,
-                      m.icDataDefs,
-                      semmedNif = toNifFilename(m.config, FileIndex m.module.position),
-                      moduleBase = getSomeNameForModule(m),
-                      implDeps = implDeps)
-    m.g.graph.icCnifFiles.add artifact
-  # NB: under cmdNifC the returned text still carries the cnif marks; the
-  # caller renders it (dropping dead definitions) or strips it.
-
 proc initProcOptions(m: BModule): TOptions =
   let opts = m.config.options
   if sfSystemModule in m.module.flags: opts-{optStackTrace} else: opts
@@ -2523,8 +2360,6 @@ proc rawNewModule(g: BModuleList; module: PSym, filename: AbsoluteFile): BModule
   result.headerFiles = @[]
   result.declaredThings = initIntSet()
   result.declaredProtos = initIntSet()
-  result.emittedContentDefs = initHashSet[string]()
-  result.icImplMods = initIntSet()
   result.cfilename = filename
   result.filename = filename
   result.typeCache = initTable[SigHash, Rope]()
@@ -2596,13 +2431,10 @@ proc writeHeader(m: BModule) =
     result.finishProcHeaderAsProto()
   if m.config.cppCustomNamespace.len > 0: closeNamespaceNim(result)
   result.addf("#endif /* $1 */$n", [guard])
-  var headerText = extract(result)
-  if m.config.cmd == cmdNifC:
-    headerText = stripCnifMarks(headerText)
-  if not writeRope(headerText, m.filename):
+  if not writeRope(extract(result), m.filename):
     rawMessage(m.config, errCannotOpenFile, m.filename.string)
 
-proc getCFile*(m: BModule): AbsoluteFile =
+proc getCFile(m: BModule): AbsoluteFile =
   let ext =
       if m.compileToCpp: ".nim.cpp"
       elif m.config.backend == backendObjc or sfCompileToObjc in m.module.flags: ".nim.m"
@@ -2696,9 +2528,8 @@ proc shouldRecompile(m: BModule; code: Rope, cfile: Cfile): bool =
       rawMessage(m.config, errCannotOpenFile, cfile.cname.string)
     result = true
 
-proc genModuleCode(m: BModule; cf: var Cfile): string =
-  ## First half of `writeModule`: finalizes the module and produces its code
-  ## text. Under cmdNifC the text still carries the cnif marks.
+proc writeModule(m: BModule) =
+  let cfile = getCFile(m)
   if moduleHasChanged(m.g.graph, m.module):
     genInitCode(m)
 
@@ -2713,11 +2544,9 @@ proc genModuleCode(m: BModule; cf: var Cfile): string =
       m.s[cfsProcHeaders].add(extract(m.g.mainModProcs))
       generateThreadVarsSize(m)
 
-  result = genModule(m, cf)
-
-proc registerModuleCode(m: BModule; cf: var Cfile; code: string) =
-  ## Second half of `writeModule`: writes the .c file if it changed and
-  ## registers it for compilation.
+  var cf = Cfile(nimname: m.module.name.s, cname: cfile,
+                  obj: completeCfilePath(m.config, toObjFile(m.config, cfile)), flags: {})
+  var code = genModule(m, cf)
   if code != "" or m.config.symbolFiles != disabledSf:
     when hasTinyCBackend:
       if m.config.cmd == cmdTcc:
@@ -2727,15 +2556,6 @@ proc registerModuleCode(m: BModule; cf: var Cfile; code: string) =
     if not shouldRecompile(m, code, cf): cf.flags = {CfileFlag.Cached}
     addFileToCompile(m.config, cf)
 
-proc writeModule(m: BModule) =
-  let cfile = getCFile(m)
-  var cf = Cfile(nimname: m.module.name.s, cname: cfile,
-                  obj: completeCfilePath(m.config, toObjFile(m.config, cfile)), flags: {})
-  var code = genModuleCode(m, cf)
-  if m.config.cmd == cmdNifC:
-    code = stripCnifMarks(code)
-  registerModuleCode(m, cf, code)
-
 proc updateCachedModule(m: BModule) =
   let cfile = getCFile(m)
   var cf = Cfile(nimname: m.module.name.s, cname: cfile,
@@ -2814,20 +2634,15 @@ proc finalCodegenActions*(graph: ModuleGraph; m: BModule; n: PNode) =
         cgsym(m, "rawWrite")
 
       # raise dependencies on behalf of genMainProc
-      if m.config.target.targetOS != osStandalone and m.config.selectedGC notin {gcNone, gcArc, gcAtomicArc, gcOrc, gcYrc}:
+      if m.config.target.targetOS != osStandalone and m.config.selectedGC notin {gcNone, gcArc, gcAtomicArc, gcOrc}:
         cgsym(m, "initStackBottomWith")
       if emulatedThreadVars(m.config) and m.config.target.targetOS != osStandalone:
         cgsym(m, "initThreadVarsEmulation")
 
       if m.g.forwardedProcs.len == 0:
         incl m.flags, objHasKidsValid
-      if m.config.cmd == cmdNifC:
-        # nifbackend synthesizes the dispatchers between the module loop
-        # and the finish loop (emitMethodDispatchers): TUs demand-created
-        # by the dispatcher bodies must still reach `modulesClosed`
-        discard
-      elif optMultiMethods in m.g.config.globalOptions or
-          m.g.config.selectedGC notin {gcArc, gcOrc, gcAtomicArc, gcYrc} or
+      if optMultiMethods in m.g.config.globalOptions or
+          m.g.config.selectedGC notin {gcArc, gcOrc, gcAtomicArc} or
           vtables notin m.g.config.features:
         generateIfMethodDispatchers(graph, m.idgen)
 
@@ -2840,8 +2655,9 @@ proc genForwardedProcs(g: BModuleList) =
   # a second pass here
   # Note: ``genProcLvl2`` may add to ``forwardedProcs``
   while g.forwardedProcs.len > 0:
-    let prc = g.forwardedProcs.pop()
-    let m = g.mods[prc.itemId.module]
+    let
+      prc = g.forwardedProcs.pop()
+      m = g.mods[prc.itemId.module]
     if sfForward in prc.flags:
       internalError(m.config, prc.info, "still forwarded: " & prc.name.s)
 
@@ -2856,32 +2672,7 @@ proc cgenWriteModules*(backend: RootRef, config: ConfigRef) =
   # order anyway)
   genForwardedProcs(g)
 
-  if config.cmd == cmdNifC and not isDefined(config, "icNoCDce"):
-    # Two-phase write: produce every module's marked text and artifact
-    # first, then compute global liveness over the artifacts and render
-    # the .c files with dead definitions dropped. Demand-driven codegen
-    # over-approximates (it cannot retract a definition once some path
-    # requested it); this is where the surplus is removed.
-    var mods: seq[BModule] = @[]
-    var cfs: seq[Cfile] = @[]
-    var codes: seq[string] = @[]
-    for m in cgenModules(g):
-      let cfile = getCFile(m)
-      var cf = Cfile(nimname: m.module.name.s, cname: cfile,
-                     obj: completeCfilePath(m.config, toObjFile(m.config, cfile)), flags: {})
-      let code = genModuleCode(m, cf)
-      mods.add m
-      cfs.add cf
-      codes.add code
-    let cl = computeLiveFromCArtifacts(g.graph.icCnifFiles)
-    var dropped = 0
-    for i in 0..<mods.len:
-      let rendered =
-        if cl.broken: stripCnifMarks(codes[i])
-        else: renderMarkedC(codes[i], cl.live, dropped)
-      registerModuleCode(mods[i], cfs[i], rendered)
-  else:
-    for m in cgenModules(g):
-      m.writeModule()
+  for m in cgenModules(g):
+    m.writeModule()
   writeMapping(config, g.mapping)
   if g.generatedHeader != nil: writeHeader(g.generatedHeader)

compiler/cgendata.nim

@@ -75,13 +75,10 @@ type
     flags*: set[TCProcFlag]
     lastLineInfo*: TLineInfo  # to avoid generating excessive 'nimln' statements
     currLineInfo*: TLineInfo  # AST codegen will make this superfluous
-    nestedTryStmts*: seq[tuple[fin: PNode, inExcept: bool, isHidden: bool, label: Natural]]
+    nestedTryStmts*: seq[tuple[fin: PNode, inExcept: bool, label: Natural]]
                               # in how many nested try statements we are
                               # (the vars must be volatile then)
-                              # `inExcept` is true when we are in the except part of a try block.
-                              # `isHidden` is true for compiler-injected `nkHiddenTryStmt` wrappers
-                              # (e.g. ARC's destructor try/finally around `except T as e:` bodies);
-                              # finallyActions walks past such wrappers to reach the user's try.
+                              # bool is true when are in the except part of a try block
     finallySafePoints*: seq[Rope]  # For correctly cleaning up exceptions when
                                    # using return in finally statements
     labels*: Natural          # for generating unique labels in the C proc
@@ -158,12 +155,6 @@ type
     forwTypeCache*: TypeCache # cache for forward declarations of types
     declaredThings*: IntSet   # things we have declared in this .c file
     declaredProtos*: IntSet   # prototypes we have declared in this .c file
-    emittedContentDefs*: HashSet[string]
-      # cmdNifC per-module backend: content-addressed C names (generic
-      # instances and synthesized hooks) whose body this TU already emitted.
-      # Distinct symbols (minted in different source modules) can share one
-      # `_i<disamb>` name; `declaredThings` keys on symbol id and lets the
-      # second one through, so we dedup the body by name here instead.
     queue*: seq[PSym]         # queue of procs to generate
     alive*: IntSet            # symbol IDs of alive data as computed by `dce.nim`
     headerFiles*: seq[string] # needed headers to include
@@ -182,17 +173,6 @@ type
     extensionLoaders*: array['0'..'9', Builder] # special procs for the
                                              # OpenGL wrapper
     sigConflicts*: CountTable[SigHash]
-    icImplMods*: IntSet       # module ids whose routine BODIES this TU
-                              # embeds (redirected defs, shared instances,
-                              # hooks); recorded as the artifact's cdeps so
-                              # the reuse gate can check their impl cookies
-    icDataDefs*: seq[tuple[cname, nifname: string]]
-                              # C names of data definitions (consts, globals,
-                              # RTTI) this TU embeds plus their NIF symbol
-                              # names (empty for RTTI, which has no symbol);
-                              # recorded in the cnif artifact so a later run
-                              # can reuse the TU and re-demand definitions
-                              # that cached TUs still reference
     g*: BModuleList
 
 template config*(m: BModule): ConfigRef = m.g.config

compiler/cgmeth.nim

@@ -180,7 +180,6 @@ proc methodDef*(g: ModuleGraph; idgen: IdGenerator; s: PSym) =
            g.methods[i].methods[0] != s:
         # already exists due to forwarding definition?
         localError(g.config, s.info, "method is not a base")
-      logMethodDef(g, s)
       return
     of No: discard
     of Invalid:
@@ -192,7 +191,6 @@ proc methodDef*(g: ModuleGraph; idgen: IdGenerator; s: PSym) =
   else:
     g.bucketTable.inc(s.typ.firstParamType.skipTypes(skipPtrs).itemId)
   g.methods.add((methods: @[s], dispatcher: createDispatcher(s, g, idgen)))
-  logMethodDef(g, s)
   #echo "adding ", s.info
   if witness != nil:
     localError(g.config, s.info, "invalid declaration order; cannot attach '" & s.name.s &

compiler/closureiters.nim

@@ -139,7 +139,7 @@
 
 import
   ast, msgs, idents,
-  renderer, magicsys, lowerings, lambdalifting, modulegraphs, lineinfos, trees
+  renderer, magicsys, lowerings, lambdalifting, modulegraphs, lineinfos
 
 import std/tables
 
@@ -167,8 +167,6 @@ type
     curExcSym: PSym # Current exception
     externExcSym: PSym # Extern exception: what would getCurrentException() return outside of closure iter
 
-    enclosingPragmas: seq[PNode] # stack of pragma blocks wrapping stmtlist
-
     states: seq[State] # The resulting states. Label is int literal.
     finallyPathStack: seq[FinallyTarget] # Stack of split blocks, whiles and finallies
     stateLoopLabel: PSym # Label to break on, when jumping between states.
@@ -254,8 +252,7 @@ proc newCurExcAccess(ctx: var Ctx): PNode =
   ctx.newEnvVarAccess(ctx.curExcSym)
 
 proc newStateLabel(ctx: Ctx): PNode =
-  result = nkIntLit.newIntNode(0)
-  result.typ = getSysType(ctx.g, TLineInfo(), tyInt16)
+  ctx.g.newIntLit(TLineInfo(), 0)
 
 proc newState(ctx: var Ctx, n: PNode, inlinable: bool, label: PNode): PNode =
   # Creates a new state, adds it to the context
@@ -595,7 +592,10 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
           let branch = n[i]
           case branch.kind
           of nkExceptBranch:
-            branch[^1] = ctx.convertExprBodyToAsgn(branch[^1], tmp)
+            if branch[0].kind == nkType:
+              branch[1] = ctx.convertExprBodyToAsgn(branch[1], tmp)
+            else:
+              branch[0] = ctx.convertExprBodyToAsgn(branch[0], tmp)
           of nkFinally:
             discard
           else:
@@ -727,7 +727,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
       n[0] = ex
       result.add(n)
 
-  of nkCast, nkHiddenStdConv, nkHiddenSubConv, nkConv, nkObjDownConv, nkObjUpConv,
+  of nkCast, nkHiddenStdConv, nkHiddenSubConv, nkConv, nkObjDownConv,
       nkDerefExpr, nkHiddenDeref:
     var ns = false
     for i in ord(n.kind == nkCast)..<n.len:
@@ -985,14 +985,9 @@ proc transformClosureIteratorBody(ctx: var Ctx, n: PNode, gotoOut: PNode): PNode
         for j in i + 1..<n.len:
           s.add(n[j])
 
-        var body = s
-        for pragma in ctx.enclosingPragmas:
-          body = newTreeI(nkPragmaBlock, n[i + 1].info,
-                          pragma[0].copyTree, body)
-
         n.sons.setLen(i + 1)
-        discard ctx.newState(body, true, label)
-        if ctx.transformClosureIteratorBody(body, gotoOut) != body:
+        discard ctx.newState(s, true, label)
+        if ctx.transformClosureIteratorBody(s, gotoOut) != s:
           internalError(ctx.g.config, "transformClosureIteratorBody != s")
         break
       else:
@@ -1130,14 +1125,6 @@ proc transformClosureIteratorBody(ctx: var Ctx, n: PNode, gotoOut: PNode): PNode
         finallyBody = ctx.transformClosureIteratorBody(finallyBody, finallyExit)
         dec ctx.curFinallyLevel
 
-  of nkPragmaBlock:
-    # Propagate the pragma blocks so that blocks like {.cast(uncheckedAssign).}
-    # remain effective
-    ctx.enclosingPragmas.add(n)
-    n[1] = ctx.transformClosureIteratorBody(n[1], gotoOut)
-    discard ctx.enclosingPragmas.pop()
-    result = n
-
   of nkGotoState, nkForStmt:
     internalError(ctx.g.config, "closure iter " & $n.kind)
 
@@ -1403,34 +1390,18 @@ proc optimizeStates(ctx: var Ctx) =
   for i in 0 .. ctx.states.high:
     ctx.states[i].label.intVal = i
 
-proc detectCapturedSym(c: var Ctx, s: PSym, stateIdx: int) =
-  if s.kind in {skResult, skVar, skLet, skForVar, skTemp} and sfGlobal notin s.flags and s.owner == c.fn and s != c.externExcSym:
-    let vs = c.varStates.getOrDefault(s.itemId, localNotSeen)
-    if vs == localNotSeen: # First seing this variable
-      c.varStates[s.itemId] = stateIdx
-    elif vs == localRequiresLifting:
-      discard # Sym already marked
-    elif vs != stateIdx:
-      c.captureVar(s)
-
-proc isClosureIterLocal(c: Ctx, s: PSym): bool =
-  s.kind in {skResult, skVar, skLet, skForVar, skTemp} and
-  sfGlobal notin s.flags and s.owner == c.fn and s != c.externExcSym
-
 proc detectCapturedVars(c: var Ctx, n: PNode, stateIdx: int) =
   case n.kind
   of nkSym:
     let s = n.sym
-    detectCapturedSym(c, s, stateIdx)
-  of nkAddr, nkHiddenAddr:
-    let s = getRoot(n)
-    if s != nil and isClosureIterLocal(c, s):
-      detectCapturedSym(c, s, stateIdx)
-      # bug #25596; lifetime extension for `addr`-taken locals as
-      # we claim ARC/ORC do destruction based on scopes, not on last-usages.
-      c.captureVar(s)
-    for i in 0 ..< n.safeLen:
-      detectCapturedVars(c, n[i], stateIdx)
+    if s.kind in {skResult, skVar, skLet, skForVar, skTemp} and sfGlobal notin s.flags and s.owner == c.fn and s != c.externExcSym:
+      let vs = c.varStates.getOrDefault(s.itemId, localNotSeen)
+      if vs == localNotSeen: # First seing this variable
+        c.varStates[s.itemId] = stateIdx
+      elif vs == localRequiresLifting:
+        discard # Sym already marked
+      elif vs != stateIdx:
+        c.captureVar(s)
   of nkReturnStmt:
     if n[0].kind in {nkAsgn, nkFastAsgn, nkSinkAsgn}:
       # we have a `result = result` expression produced by the closure

compiler/cnif.nim

@@ -1,726 +0,0 @@
-#
-#
-#           The Nim Compiler
-#        (c) Copyright 2026 Andreas Rumpf
-#
-#    See the file "copying.txt", included in this
-#    distribution, for details about the copyright.
-#
-
-## The "cnif" artifact: the C code generator's output as a NIF file.
-##
-## This is deliberately *not* NIFC: the C text is kept verbatim (Nim's
-## C-level machinery — exception handling in particular — is more refined
-## than what NIFC models today; the gap can be closed incrementally later).
-## The only structure the artifact adds is the part dead code elimination
-## and generic-instance merging need:
-##
-## - raw C text as string literals
-## - every *global* entity's C name as a `Symbol` token
-## - every emitted proc definition as a `(cdef SymbolDef flags ...)` group
-##
-## The C generator marks names with control characters at the single place
-## a global's C name is minted (`fillBackendName`) and emits a definition
-## directive at the single place finished procs are appended; the marks then
-## ride through all of the snippet composition untouched. This module turns
-## the final marked module text into the `.c.nif` artifact and strips the
-## marks for the actual `.c` output. Rendering C from the artifact is a
-## plain token walk: string literals verbatim, symbols by name — which is
-## also where a later merge step redirects losing generic instances.
-##
-## Marker scheme (cannot collide: C string literals escape control chars,
-## and `\1`/`\31`/`\23` of cgen's postprocess directives are distinct):
-##   \2 name \3                       a global's C name
-##   \4 name \31 flags \31 nif \5     start of the definition of `name`;
-##                                    `nif` is the defining symbol's NIF name
-##                                    (empty for backend-minted symbols) so a
-##                                    later run can re-demand the definition
-##   \4 \5                            end of the definitions section
-
-import std / [tables, sets, os, assertions, syncio, algorithm]
-import "../dist/nimony/src/lib" / [nifbuilder, nifcoreparse]
-
-const
-  CnifSymStart* = '\2'
-  CnifSymEnd* = '\3'
-  CnifDefStart* = '\4'
-  CnifDefSep* = '\31'   # same separator char as cgen's postprocess directives
-  CnifDefEnd* = '\5'
-
-proc markCName*(name: string): string {.inline.} =
-  CnifSymStart & name & CnifSymEnd
-
-proc hasCnifMarks*(s: string): bool =
-  for c in s:
-    if c in {CnifSymStart, CnifSymEnd, CnifDefStart}: return true
-  false
-
-proc stripCnifMarks*(s: string): string =
-  ## Removes the symbol marks (keeping the names) and the definition
-  ## directives (entirely) so the result is plain C.
-  if not hasCnifMarks(s): return s
-  result = newStringOfCap(s.len)
-  var i = 0
-  while i < s.len:
-    case s[i]
-    of CnifSymStart, CnifSymEnd:
-      inc i
-    of CnifDefStart:
-      while i < s.len and s[i] != CnifDefEnd: inc i
-      inc i # skip CnifDefEnd
-    else:
-      result.add s[i]
-      inc i
-
-const
-  CnifVersion* = "4"
-    ## Artifact format version, stored in the meta head. Artifacts written
-    ## by an older compiler lack the NIF names and the cref group the
-    ## def-retention check needs (v2), the cdeps group the fine-grained
-    ## reuse gate needs (v3), or the type NIF names and cnif-marked extern
-    ## RTTI references the typeinfo flavor of the def-retention check
-    ## needs (v4); `readCnifHeads` reports them as invalid so their TUs
-    ## simply regenerate once.
-
-proc cnifDefDirective*(name, flags, nifName: string): string =
-  CnifDefStart & name & CnifDefSep & flags & CnifDefSep & nifName & CnifDefEnd
-
-proc cnifEndDefs*(): string =
-  CnifDefStart & CnifDefEnd
-
-proc writeCnifArtifact*(code: string; outfile: string;
-                        initRequired = false; datInitRequired = false;
-                        dataDefs: openArray[tuple[cname, nifname: string]] = [];
-                        semmedNif = ""; moduleBase = "";
-                        implDeps: openArray[string] = []) =
-  ## Splits the marked module text into the `.c.nif` artifact.
-  ## The artifact starts with a `(meta <flags> "semmedNif" "moduleBase"
-  ## "version")` head — whether the module has an init/datInit proc
-  ## ('i'/'d'), which semmed NIF it was generated from and the module's
-  ## mangled base name (what `registerModuleToMain` and the reuse decision
-  ## need when the TU is reused in a later run, possibly without the module
-  ## ever being loaded again) — a `(cdata (SymbolDef StrLit)*)` group naming
-  ## the data definitions (consts, globals, RTTI) the TU embeds together
-  ## with their NIF names, a `(cref Ident*)` group naming every C name
-  ## the TU references but does not define itself (what the def-retention
-  ## check consults when some *other* TU regenerates), and a
-  ## `(cdeps Ident*)` group naming the modules whose routine *bodies* this
-  ## TU embeds (redirected defs, shared instances, hooks): the fine-grained
-  ## reuse gate checks their `.impl.nif` cookies on top of the direct
-  ## imports' `.iface.nif` cookies.
-  # pre-pass: every marked name is a use, every definition directive (and
-  # every data def) is a definition; external references = uses - defs
-  var uses = initHashSet[string]()
-  var defs = initHashSet[string]()
-  block prePass:
-    var i = 0
-    while i < code.len:
-      case code[i]
-      of CnifSymStart:
-        inc i
-        var name = ""
-        while i < code.len and code[i] != CnifSymEnd:
-          name.add code[i]
-          inc i
-        inc i
-        uses.incl name
-      of CnifDefStart:
-        inc i
-        var payload = ""
-        while i < code.len and code[i] != CnifDefEnd:
-          payload.add code[i]
-          inc i
-        inc i
-        let sep = find(payload, CnifDefSep)
-        if sep > 0: defs.incl payload[0..<sep]
-        elif payload.len > 0: defs.incl payload
-      else:
-        inc i
-  for d in dataDefs: defs.incl d.cname
-  var crefs: seq[string] = @[]
-  for u in uses:
-    if u notin defs: crefs.add u
-  sort crefs
-
-  var b = nifbuilder.open(outfile)
-  b.withTree "stmts":
-    b.withTree "meta":
-      var metaFlags = ""
-      if initRequired: metaFlags.add 'i'
-      if datInitRequired: metaFlags.add 'd'
-      if metaFlags.len > 0: b.addIdent metaFlags
-      else: b.addEmpty
-      b.addStrLit semmedNif
-      b.addStrLit moduleBase
-      b.addStrLit CnifVersion
-    b.withTree "cdata":
-      for d in dataDefs:
-        b.addSymbolDef d.cname
-        b.addStrLit d.nifname
-    b.withTree "cref":
-      for r in crefs:
-        b.addIdent r
-    b.withTree "cdeps":
-      for s in implDeps:
-        b.addIdent s
-    var raw = ""
-    var inDef = false
-    template flushRaw() =
-      if raw.len > 0:
-        b.addStrLit raw
-        raw.setLen 0
-    var i = 0
-    while i < code.len:
-      case code[i]
-      of CnifSymStart:
-        flushRaw()
-        inc i
-        var name = ""
-        while i < code.len and code[i] != CnifSymEnd:
-          name.add code[i]
-          inc i
-        inc i # skip CnifSymEnd
-        b.addSymbol name, ""
-      of CnifDefStart:
-        flushRaw()
-        inc i
-        var payload = ""
-        while i < code.len and code[i] != CnifDefEnd:
-          payload.add code[i]
-          inc i
-        inc i # skip CnifDefEnd
-        if inDef:
-          b.endTree()
-          inDef = false
-        if payload.len > 0:
-          let sep = find(payload, CnifDefSep)
-          let name = if sep >= 0: payload[0..<sep] else: payload
-          var flags = if sep >= 0: payload[sep+1..^1] else: ""
-          var nifName = ""
-          let sep2 = find(flags, CnifDefSep)
-          if sep2 >= 0:
-            nifName = flags[sep2+1..^1]
-            flags = flags[0..<sep2]
-          b.addTree "cdef"
-          b.addSymbolDef name
-          if flags.len > 0: b.addIdent flags
-          else: b.addEmpty
-          b.addStrLit nifName
-          inDef = true
-      else:
-        raw.add code[i]
-        inc i
-    flushRaw()
-    if inDef:
-      b.endTree()
-  b.close()
-
-proc renderMarkedC*(code: string; live: HashSet[string]; dropped: var int): string =
-  ## Renders the final C text from the marked module text: symbol marks are
-  ## removed (keeping the names — a later merge step substitutes them here),
-  ## and definitions whose name is not in `live` are dropped entirely. Each
-  ## definition is self-delimiting (genProcAux emits an end directive right
-  ## after the proc's text), so text written by other emitters is never part
-  ## of a definition's span and survives unconditionally.
-  result = newStringOfCap(code.len)
-  var i = 0
-  while i < code.len:
-    case code[i]
-    of CnifSymStart, CnifSymEnd:
-      inc i
-    of CnifDefStart:
-      var payload = ""
-      inc i
-      while i < code.len and code[i] != CnifDefEnd:
-        payload.add code[i]
-        inc i
-      inc i # skip CnifDefEnd
-      if payload.len > 0:
-        let sep = find(payload, CnifDefSep)
-        let name = if sep >= 0: payload[0..<sep] else: payload
-        if name notin live:
-          inc dropped
-          # drop the definition's text: everything up to its end directive
-          while i < code.len and code[i] != CnifDefStart: inc i
-    else:
-      result.add code[i]
-      inc i
-
-# ---- Liveness over the artifact -------------------------------------------
-
-proc symOrIdentName(c: Cursor): string {.inline.} =
-  if c.kind == Ident: strVal(c) else: symName(c)
-
-type
-  CnifHeads* = object
-    ## The cheap-to-parse part of an artifact that a later run needs in
-    ## order to reuse the TU without regenerating it.
-    valid*: bool             ## file parsed, carries the meta head and has
-                             ## the current format version
-    initRequired*: bool
-    datInitRequired*: bool
-    semmedNif*: string       ## the semmed NIF this TU was generated from
-    moduleBase*: string      ## the module's mangled base name
-    cdefs*: seq[tuple[cname, nifname: string]] ## the proc definitions
-    cdata*: seq[tuple[cname, nifname: string]] ## the data definitions
-    crefs*: seq[string]      ## C names referenced but not defined here
-    cdeps*: seq[string]      ## module suffixes whose routine bodies this
-                             ## TU embeds (impl-cookie gated on reuse)
-
-proc readCnifHeads*(f: string): CnifHeads =
-  ## Reads `(meta ...)`, `(cdata ...)`, `(cref ...)` and the `(cdef ...)`
-  ## head names from an artifact. Artifacts written by an older compiler
-  ## (no meta head or a different format version) report `valid=false`.
-  result = CnifHeads()
-  if not fileExists(f): return
-  var pool = newPool()
-  var tags = newTagPool()
-  let stmtsTag = tags.registerTag("stmts")
-  let cdefTag = tags.registerTag("cdef")
-  let cdataTag = tags.registerTag("cdata")
-  let crefTag = tags.registerTag("cref")
-  let cdepsTag = tags.registerTag("cdeps")
-  let metaTag = tags.registerTag("meta")
-  var buf = parseFromFile(f, 1000, pool, tags)
-  var c = beginRead(buf)
-  if c.kind != TagLit or c.cursorTagId != stmtsTag:
-    endRead(c)
-    return
-  var version = ""
-  var sawMeta = false
-  c.loopInto:
-    if c.kind == TagLit:
-      if c.cursorTagId == metaTag:
-        sawMeta = true
-        var strIdx = 0
-        c.loopInto:
-          if c.kind == Ident:
-            for ch in strVal(c):
-              if ch == 'i': result.initRequired = true
-              elif ch == 'd': result.datInitRequired = true
-            inc c
-          elif c.kind == StrLit:
-            if strIdx == 0: result.semmedNif = strVal(c)
-            elif strIdx == 1: result.moduleBase = strVal(c)
-            elif strIdx == 2: version = strVal(c)
-            inc strIdx
-            inc c
-          else:
-            skip c
-      elif c.cursorTagId == cdataTag:
-        c.loopInto:
-          if c.kind == SymbolDef:
-            result.cdata.add (symName(c), "")
-            inc c
-          elif c.kind == StrLit:
-            if result.cdata.len > 0:
-              result.cdata[^1].nifname = strVal(c)
-            inc c
-          else:
-            skip c
-      elif c.cursorTagId == crefTag:
-        c.loopInto:
-          if c.kind in {Ident, Symbol, SymbolDef}:
-            result.crefs.add symOrIdentName(c)
-            inc c
-          else:
-            skip c
-      elif c.cursorTagId == cdepsTag:
-        c.loopInto:
-          if c.kind in {Ident, Symbol, SymbolDef}:
-            result.cdeps.add symOrIdentName(c)
-            inc c
-          else:
-            skip c
-      elif c.cursorTagId == cdefTag:
-        # fixed head: SymbolDef, flags (Ident or empty), NIF name StrLit;
-        # everything after that is the definition's body text
-        var state = 0
-        c.loopInto:
-          if c.kind == SymbolDef:
-            result.cdefs.add (symName(c), "")
-            state = 1
-            inc c
-          elif state == 1: # the flags field
-            state = 2
-            skip c
-          elif state == 2: # the NIF name
-            if c.kind == StrLit and result.cdefs.len > 0:
-              result.cdefs[^1].nifname = strVal(c)
-            state = 3
-            skip c
-          else:
-            skip c
-      else:
-        skip c
-    else:
-      skip c
-  endRead(c)
-  result.valid = sawMeta and version == CnifVersion
-
-type
-  CnifLiveness* = object
-    defs*: int      ## proc definitions emitted across all modules
-    liveDefs*: int  ## of those, reachable from the roots
-    live*: HashSet[string] ## live C names
-    broken*: bool
-
-proc computeLiveFromCArtifacts*(files: openArray[string]): CnifLiveness =
-  ## dce1-style mark&sweep over the C-shaped artifacts: a `(cdef ...)`
-  ## group is a definition (flags 'x'/'c'/'m' — exportc, compilerproc,
-  ## method/dispatcher — make it a root), names at the top level (data,
-  ## globals, init code) are roots, names inside a group are its uses.
-  ## Because the artifact is *fully lowered* output, no conservative
-  ## modelling is needed: every call the C code contains is a token here.
-  ##
-  ## NB: mangled C names contain no dots, so NIF's text reader classifies
-  ## them as `Ident` rather than `Symbol`; the dialect therefore treats
-  ## Ident tokens as name uses. Inside a `(cdef ...)` the flags ident is
-  ## the one immediately following the SymbolDef; everything after is a use.
-  result = CnifLiveness(live: initHashSet[string]())
-  var pool = newPool()
-  var tags = newTagPool()
-  let stmtsTag = tags.registerTag("stmts")
-  let cdefTag = tags.registerTag("cdef")
-  let cdataTag = tags.registerTag("cdata")
-  let crefTag = tags.registerTag("cref")
-  let cdepsTag = tags.registerTag("cdeps")
-  let metaTag = tags.registerTag("meta")
-  var uses = initTable[string, HashSet[string]]()
-  var roots = initHashSet[string]()
-  var defs = initHashSet[string]()
-  for f in files:
-    if not fileExists(f):
-      result.broken = true
-      return
-    var buf = parseFromFile(f, 1000, pool, tags)
-    var c = beginRead(buf)
-    if c.kind != TagLit or c.cursorTagId != stmtsTag:
-      result.broken = true
-      endRead(c)
-      return
-    c.loopInto:
-      case c.kind
-      of Symbol, Ident:
-        roots.incl symOrIdentName(c)
-        inc c
-      of TagLit:
-        if c.cursorTagId == metaTag or c.cursorTagId == cdataTag or
-            c.cursorTagId == crefTag or c.cursorTagId == cdepsTag:
-          # bookkeeping for TU reuse, irrelevant for liveness
-          skip c
-        elif c.cursorTagId == cdefTag:
-          var owner = ""
-          var flagsSeen = false
-          c.loopInto:
-            case c.kind
-            of SymbolDef:
-              owner = symName(c)
-              defs.incl owner
-              flagsSeen = false
-              inc c
-            of Symbol, Ident:
-              let name = symOrIdentName(c)
-              if not flagsSeen:
-                # the flags field right after the SymbolDef
-                flagsSeen = true
-                for ch in name:
-                  # 'd' marks a data definition (const/RTTI): never DCE'd, so it
-                  # is a root whose body keeps its referenced procs live
-                  if ch in {'x', 'c', 'm', 'd'}:
-                    roots.incl owner
-                    break
-              else:
-                uses.mgetOrPut(owner, initHashSet[string]()).incl name
-              inc c
-            of DotToken:
-              flagsSeen = true # empty flags field
-              inc c
-            else:
-              skip c
-        else:
-          c.loopInto:
-            if c.kind in {Symbol, Ident}:
-              roots.incl symOrIdentName(c)
-              inc c
-            else:
-              skip c
-      else:
-        skip c
-    endRead(c)
-  # mark & sweep
-  var work = newSeqOfCap[string](roots.len)
-  for r in roots: work.add r
-  while work.len > 0:
-    let s = work.pop()
-    if not result.live.containsOrIncl(s):
-      if uses.hasKey(s):
-        for dep in uses[s]:
-          if dep notin result.live:
-            work.add dep
-  result.defs = defs.len
-  for d in defs:
-    if d in result.live: inc result.liveDefs
-
-# ---- The merge stage: liveness + owner assignment -------------------------
-
-type
-  MergeDecision* = object
-    ## What the per-module backend's `merge` stage computes from every
-    ## module's `.c.nif` and what its `emit` stage consumes to render the
-    ## final `.c` of one module.
-    live*: HashSet[string]        ## globally reachable C names (dead cdefs
-                                  ## are dropped from every module)
-    owners*: Table[string, string] ## for each `'u'`-flagged (unique,
-                                  ## externally-linked) definition, the single
-                                  ## artifact base name allowed to embed its
-                                  ## body; every other module prototypes it
-    broken*: bool                 ## an artifact was missing or unparsable —
-                                  ## the caller should fall back / regenerate
-    defs*, liveDefs*: int
-
-proc computeMergeDecision*(files: openArray[string]): MergeDecision =
-  ## One pass over every `.c.nif`: the same mark&sweep as
-  ## `computeLiveFromCArtifacts` plus, per definition, owner assignment.
-  ##
-  ## Each `cg` process emits the body of every definition it demands
-  ## (emit-everywhere), so the same externally-linked definition appears in
-  ## several artifacts. A `'u'` flag on the `(cdef ...)` marks those that need
-  ## exactly one owner, assigned here across processes: the owner is the
-  ## lexicographically smallest artifact that emits it — a pure function of the
-  ## claimant set, hence stable across rebuilds. Definitions without `'u'`
-  ## (inline procs, dispatchers) are `static`/main-only and emitted into every
-  ## using TU, so they get no owner entry and are never deduplicated.
-  result = MergeDecision(live: initHashSet[string](),
-                         owners: initTable[string, string]())
-  var pool = newPool()
-  var tags = newTagPool()
-  let stmtsTag = tags.registerTag("stmts")
-  let cdefTag = tags.registerTag("cdef")
-  let cdataTag = tags.registerTag("cdata")
-  let crefTag = tags.registerTag("cref")
-  let cdepsTag = tags.registerTag("cdeps")
-  let metaTag = tags.registerTag("meta")
-  var uses = initTable[string, HashSet[string]]()
-  var roots = initHashSet[string]()
-  var defs = initHashSet[string]()
-  for f in files:
-    if not fileExists(f):
-      result.broken = true
-      return
-    let owner = extractFilename(f)
-    var buf = parseFromFile(f, 1000, pool, tags)
-    var c = beginRead(buf)
-    if c.kind != TagLit or c.cursorTagId != stmtsTag:
-      result.broken = true
-      endRead(c)
-      return
-    c.loopInto:
-      case c.kind
-      of Symbol, Ident:
-        roots.incl symOrIdentName(c)
-        inc c
-      of TagLit:
-        if c.cursorTagId == metaTag or c.cursorTagId == cdataTag or
-            c.cursorTagId == crefTag or c.cursorTagId == cdepsTag:
-          skip c
-        elif c.cursorTagId == cdefTag:
-          var ownerName = ""
-          var flagsSeen = false
-          var needsOwner = false
-          c.loopInto:
-            case c.kind
-            of SymbolDef:
-              ownerName = symName(c)
-              defs.incl ownerName
-              flagsSeen = false
-              inc c
-            of Symbol, Ident:
-              let name = symOrIdentName(c)
-              if not flagsSeen:
-                flagsSeen = true
-                for ch in name:
-                  if ch in {'x', 'c', 'm'}: roots.incl ownerName
-                  # 'u' = unique proc (DCE'd), 'd' = data (never DCE'd, hence a
-                  # root); both need a single owner across the emit-everywhere
-                  # processes
-                  elif ch == 'u': needsOwner = true
-                  elif ch == 'd':
-                    needsOwner = true
-                    roots.incl ownerName
-              else:
-                uses.mgetOrPut(ownerName, initHashSet[string]()).incl name
-              inc c
-            of DotToken:
-              flagsSeen = true # empty flags field
-              inc c
-            else:
-              skip c
-          if needsOwner and ownerName.len > 0:
-            # smallest claimant wins; ties impossible (one entry per name)
-            let prev = result.owners.getOrDefault(ownerName, "")
-            if prev.len == 0 or owner < prev:
-              result.owners[ownerName] = owner
-        else:
-          c.loopInto:
-            if c.kind in {Symbol, Ident}:
-              roots.incl symOrIdentName(c)
-              inc c
-            else:
-              skip c
-      else:
-        skip c
-    endRead(c)
-  var work = newSeqOfCap[string](roots.len)
-  for r in roots: work.add r
-  while work.len > 0:
-    let s = work.pop()
-    if not result.live.containsOrIncl(s):
-      if uses.hasKey(s):
-        for dep in uses[s]:
-          if dep notin result.live:
-            work.add dep
-  result.defs = defs.len
-  for d in defs:
-    if d in result.live: inc result.liveDefs
-
-const MergeDecisionFile* = "ic.backend.merge.nif"
-  ## Fixed name of the merge stage's output in the nimcache, read by `emit`.
-
-proc writeMergeDecision*(outfile: string; d: MergeDecision) =
-  ## Serializes the merge decision: `(merge (live Symbol*) (owners (own
-  ## Symbol StrLit)*))`. C names are mangled (no dots) so they serialize as
-  ## symbols; owner artifact base names go in string literals.
-  var live: seq[string] = @[]
-  for n in d.live: live.add n
-  sort live
-  var keys: seq[string] = @[]
-  for k in d.owners.keys: keys.add k
-  sort keys
-  var b = nifbuilder.open(outfile)
-  b.withTree "merge":
-    b.withTree "live":
-      for n in live: b.addSymbol n, ""
-    b.withTree "owners":
-      for k in keys:
-        b.withTree "own":
-          b.addSymbol k, ""
-          b.addStrLit d.owners[k]
-  b.close()
-
-proc readMergeDecision*(f: string): MergeDecision =
-  ## Reads back a `writeMergeDecision` file; `broken=true` if absent/unparsable.
-  result = MergeDecision(live: initHashSet[string](),
-                         owners: initTable[string, string]())
-  if not fileExists(f):
-    result.broken = true
-    return
-  var pool = newPool()
-  var tags = newTagPool()
-  let mergeTag = tags.registerTag("merge")
-  let liveTag = tags.registerTag("live")
-  let ownersTag = tags.registerTag("owners")
-  let ownTag = tags.registerTag("own")
-  var buf = parseFromFile(f, 1000, pool, tags)
-  var c = beginRead(buf)
-  if c.kind != TagLit or c.cursorTagId != mergeTag:
-    result.broken = true
-    endRead(c)
-    return
-  c.loopInto:
-    if c.kind == TagLit and c.cursorTagId == liveTag:
-      c.loopInto:
-        if c.kind in {Symbol, Ident}:
-          result.live.incl symOrIdentName(c)
-          inc c
-        else:
-          skip c
-    elif c.kind == TagLit and c.cursorTagId == ownersTag:
-      c.loopInto:
-        if c.kind == TagLit and c.cursorTagId == ownTag:
-          var key = ""
-          c.loopInto:
-            if c.kind in {Symbol, Ident}:
-              key = symOrIdentName(c)
-              inc c
-            elif c.kind == StrLit:
-              if key.len > 0: result.owners[key] = strVal(c)
-              inc c
-            else:
-              skip c
-        else:
-          skip c
-    else:
-      skip c
-  endRead(c)
-
-proc renderCFromArtifact*(artifact: string; d: MergeDecision; ownerId: string;
-                          dropped: var int): string =
-  ## The per-module backend's `emit` stage: render one module's final `.c` from
-  ## its `.c.nif` and the merge decision. String literals are emitted verbatim,
-  ## symbols by name; a `(cdef ...)` body is dropped when the name is dead, or
-  ## when it is a `'u'` unique definition this module does not own. The body's
-  ## prototype lives in the surrounding raw text (cgen emits a forward
-  ## declaration for every *used* proc, independent of where the body lands), so
-  ## a dropped body still leaves a valid declaration — no synthesis needed. The
-  ## head groups (meta/cdata/cref/cdeps) carry no C text.
-  result = ""
-  if not fileExists(artifact): return
-  var pool = newPool()
-  var tags = newTagPool()
-  let stmtsTag = tags.registerTag("stmts")
-  let cdefTag = tags.registerTag("cdef")
-  var buf = parseFromFile(artifact, 1000, pool, tags)
-  var c = beginRead(buf)
-  if c.kind != TagLit or c.cursorTagId != stmtsTag:
-    endRead(c)
-    return
-  c.loopInto:
-    case c.kind
-    of StrLit:
-      result.add strVal(c)
-      inc c
-    of Symbol, Ident:
-      result.add symOrIdentName(c)
-      inc c
-    of TagLit:
-      if c.cursorTagId == cdefTag:
-        # fixed head: SymbolDef, flags (Ident or empty), nifname StrLit; the
-        # rest is the definition's body text. `state` counts past the head.
-        var name = ""
-        var isUnique = false
-        var isData = false
-        var keep = true
-        var state = 0
-        c.loopInto:
-          if state == 0 and c.kind == SymbolDef:
-            name = symName(c)
-            state = 1
-            inc c
-          elif state == 1: # the flags field (one token: Ident/Symbol or empty)
-            if c.kind in {Ident, Symbol}:
-              for ch in symOrIdentName(c):
-                if ch == 'u': isUnique = true
-                elif ch == 'd': isData = true
-            state = 2
-            inc c
-          elif state == 2: # the NIF name (one StrLit) — decide keep here
-            let owned = d.owners.getOrDefault(name, ownerId) == ownerId
-            keep =
-              if isData: owned                      # data: kept by its owner only
-              elif isUnique: (name in d.live) and owned
-              else: name in d.live                  # inline/dispatcher: per-TU
-            if not keep: inc dropped
-            state = 3
-            inc c
-          else: # body tokens
-            if keep:
-              if c.kind == StrLit: result.add strVal(c)
-              elif c.kind in {Symbol, Ident}: result.add symOrIdentName(c)
-            inc c
-      else:
-        # head groups (meta/cdata/cref/cdeps) carry no C text
-        skip c
-    else:
-      inc c
-  endRead(c)

compiler/commands.nim

@@ -24,7 +24,7 @@ bootSwitch(usedMarkAndSweep, defined(gcmarkandsweep), "--gc:markAndSweep")
 bootSwitch(usedGoGC, defined(gogc), "--gc:go")
 bootSwitch(usedNoGC, defined(nogc), "--gc:none")
 
-import std/[setutils, sets, os, strutils, parseutils, parseopt, sequtils, strtabs, enumutils]
+import std/[setutils, os, strutils, parseutils, parseopt, sequtils, strtabs, enumutils]
 import
   msgs, options, nversion, condsyms, extccomp, platform,
   wordrecg, nimblecmd, lineinfos, pathutils
@@ -118,7 +118,7 @@ const
   errInvalidCmdLineOption = "invalid command line option: '$1'"
   errOnOrOffExpectedButXFound = "'on' or 'off' expected, but '$1' found"
   errOnOffOrListExpectedButXFound = "'on', 'off' or 'list' expected, but '$1' found"
-  errOffHintsError = "'off', 'hint', 'warning', 'error' or 'usages' expected, but '$1' found"
+  errOffHintsError = "'off', 'hint', 'error' or 'usages' expected, but '$1' found"
 
 proc invalidCmdLineOption(conf: ConfigRef; pass: TCmdLinePass, switch: string, info: TLineInfo) =
   if switch == " ": localError(conf, info, errInvalidCmdLineOption % "-")
@@ -245,12 +245,11 @@ proc processCompile(conf: ConfigRef; filename: string) =
   extccomp.addExternalFileToCompile(conf, found)
 
 const
-  errNoneBoehmRefcExpectedButXFound = "'arc', 'orc', 'yrc', 'atomicArc', 'markAndSweep', 'boehm', 'go', 'none', 'regions', or 'refc' expected, but '$1' found"
+  errNoneBoehmRefcExpectedButXFound = "'arc', 'orc', 'atomicArc', 'markAndSweep', 'boehm', 'go', 'none', 'regions', or 'refc' expected, but '$1' found"
   errNoneSpeedOrSizeExpectedButXFound = "'none', 'speed' or 'size' expected, but '$1' found"
   errGuiConsoleOrLibExpectedButXFound = "'gui', 'console', 'lib' or 'staticlib' expected, but '$1' found"
   errInvalidExceptionSystem = "'goto', 'setjmp', 'cpp' or 'quirky' expected, but '$1' found"
   errInvalidFeatureButXFound = Feature.toSeq.map(proc(val:Feature): string = "'$1'" % $val).join(", ") & " expected, but '$1' found"
-  errDefaultOrSsoExpectedButXFound = "'default' or 'sso' expected, but '$1' found"
 
 template warningOptionNoop(switch: string) =
   warningDeprecated(conf, info, "'$#' is deprecated, now a noop" % switch)
@@ -267,7 +266,6 @@ proc testCompileOptionArg*(conf: ConfigRef; switch, arg: string, info: TLineInfo
     of "markandsweep": result = conf.selectedGC == gcMarkAndSweep
     of "destructors", "arc": result = conf.selectedGC == gcArc
     of "orc": result = conf.selectedGC == gcOrc
-    of "yrc": result = conf.selectedGC == gcYrc
     of "hooks": result = conf.selectedGC == gcHooks
     of "go": result = conf.selectedGC == gcGo
     of "none": result = conf.selectedGC == gcNone
@@ -307,13 +305,6 @@ proc testCompileOptionArg*(conf: ConfigRef; switch, arg: string, info: TLineInfo
     else:
       result = false
       localError(conf, info, errInvalidExceptionSystem % arg)
-  of "strings":
-    case arg.normalize
-    of "default": result = conf.selectedStrings == stringDefault
-    of "sso": result = conf.selectedStrings == stringSso
-    else:
-      result = false
-      localError(conf, info, errDefaultOrSsoExpectedButXFound % arg)
   of "experimental":
     try:
       result = conf.features.contains parseEnum[Feature](arg)
@@ -503,12 +494,12 @@ proc parseCommand*(command: string): Command =
   of "gendepend": cmdGendepend
   of "dump": cmdDump
   of "parse": cmdParse
+  of "rod": cmdRod
   of "secret": cmdInteractive
   of "nop", "help": cmdNop
   of "jsonscript": cmdJsonscript
   of "nifc": cmdNifC  # generate C from NIF files
   of "ic": cmdIc  # generate .build.nif for nifmake
-  of "icconfig": cmdIcConfig  # produce the precompiled config artifact
   else: cmdUnknown
 
 proc setCmd*(conf: ConfigRef, cmd: Command) =
@@ -580,7 +571,6 @@ proc unregisterArcOrc*(conf: ConfigRef) =
   undefSymbol(conf.symbols, "gcdestructors")
   undefSymbol(conf.symbols, "gcarc")
   undefSymbol(conf.symbols, "gcorc")
-  undefSymbol(conf.symbols, "gcyrc")
   undefSymbol(conf.symbols, "gcatomicarc")
   undefSymbol(conf.symbols, "nimSeqsV2")
   undefSymbol(conf.symbols, "nimV2")
@@ -614,10 +604,6 @@ proc processMemoryManagementOption(switch, arg: string, pass: TCmdLinePass,
       conf.selectedGC = gcOrc
       defineSymbol(conf.symbols, "gcorc")
       registerArcOrc(pass, conf)
-    of "yrc":
-      conf.selectedGC = gcYrc
-      defineSymbol(conf.symbols, "gcyrc")
-      registerArcOrc(pass, conf)
     of "atomicarc":
       conf.selectedGC = gcAtomicArc
       defineSymbol(conf.symbols, "gcatomicarc")
@@ -654,18 +640,6 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
                     conf: ConfigRef) =
   var key = ""
   var val = ""
-  # Record config-file switches so the `nim ic` driver can serialise them into a
-  # precompiled-config artifact and have its per-module child processes replay
-  # them instead of re-parsing the `nim.cfg` chain (and re-running `config.nims`
-  # in the VM) on every invocation. Only `passPP` (config-file) switches are
-  # captured; command-line switches are forwarded by the build graph as usual.
-  # Path-search switches are skipped: their net effect already lives in the
-  # resolved `searchPaths` the driver forwards as `--path`, and replaying their
-  # raw (often relative-to-config-dir) arguments here would misresolve.
-  if pass == passPP and switch.normalize notin
-      ["path", "p", "nimblepath", "lazypath", "excludepath",
-       "nonimblepath", "clearnimblepath", "nimcache"]:
-    conf.icConfigSwitches.add (switch, arg)
   case switch.normalize
   of "eval":
     expectArg(conf, switch, arg, pass, info)
@@ -771,17 +745,6 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
     processMemoryManagementOption(switch, arg, pass, info, conf)
   of "mm":
     processMemoryManagementOption(switch, arg, pass, info, conf)
-  of "strings":
-    expectArg(conf, switch, arg, pass, info)
-    if pass in {passCmd2, passPP}:
-      case arg.normalize
-      of "default":
-        conf.selectedStrings = stringDefault
-      of "sso":
-        conf.selectedStrings = stringSso
-        defineSymbol(conf.symbols, "nimsso")
-      else:
-        localError(conf, info, errDefaultOrSsoExpectedButXFound % arg)
   of "warnings", "w":
     if processOnOffSwitchOrList(conf, {optWarns}, arg, pass, info): listWarnings(conf)
   of "warning": processSpecificNote(arg, wWarning, pass, info, switch, conf)
@@ -936,49 +899,6 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
     else: localError(conf, info, errOnOrOffExpectedButXFound % arg)
   of "noimportdoc":
     processOnOffSwitchG(conf, {optNoImportdoc}, arg, pass, info)
-  of "ismainmodule":
-    # `nim m` (IC) only: marks the single module being checked as the program's
-    # real entry point so that `isMainModule` and `when isMainModule:` resolve
-    # correctly even though every module is compiled with `sfMainModule` set.
-    conf.isMainModule = switchOn(arg)
-  of "icgroup":
-    # `nim m` only: register a module that belongs to the current strongly-
-    # connected import group, so it is compiled from source (not loaded from a
-    # precompiled NIF) and gets its own NIF written. `deps.nim` emits one
-    # `--icGroup:<path>` per member of a dependency cycle. The argument is an
-    # absolute .nim path produced by the dependency scanner.
-    expectArg(conf, switch, arg, pass, info)
-    if pass in {passCmd2, passPP}:
-      conf.icGroup.incl(canonicalizePath(conf, AbsoluteFile arg).string)
-  of "icproject":
-    # `nim m`/`nim nifc` only: the ORIGINAL project file (see options.icProject)
-    expectArg(conf, switch, arg, pass, info)
-    if pass in {passCmd2, passPP}:
-      conf.icProject = canonicalizePath(conf, AbsoluteFile arg).string
-  of "icpreparsedconfig":
-    # `nim m`/`nim nifc` only: path of the precompiled-config artifact (see
-    # options.icPreparsedConfig). Read in `passCmd1`, before `loadConfigs`, so
-    # config loading can replay it instead of re-parsing the `nim.cfg` chain.
-    expectArg(conf, switch, arg, pass, info)
-    conf.icPreparsedConfig = arg
-  of "icconfigout":
-    # `nim icconfig` only: where to write the precompiled config artifact (see
-    # options.icConfigOut). The `nim ic` driver spawns the producer with this.
-    expectArg(conf, switch, arg, pass, info)
-    conf.icConfigOut = arg
-  of "icbackendstage":
-    # `nim nifc` only: per-module backend stage, one of cg|merge|emit (see
-    # options.icBackendStage). Empty (switch unused) keeps the whole-program
-    # backend. Emitted by `deps.nim`'s backend build file.
-    expectArg(conf, switch, arg, pass, info)
-    if pass in {passCmd2, passPP}:
-      conf.icBackendStage = arg
-  of "icbackendmodule":
-    # `nim nifc` only: the NIF module suffix the cg/emit stage operates on (see
-    # options.icBackendModule).
-    expectArg(conf, switch, arg, pass, info)
-    if pass in {passCmd2, passPP}:
-      conf.icBackendModule = arg
   of "import":
     expectArg(conf, switch, arg, pass, info)
     if pass in {passCmd2, passPP}:
@@ -986,7 +906,7 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
       if m.len == 0:
         localError(conf, info, "Cannot resolve filename: " & arg)
       else:
-        conf.implicitImports.add(if arg.startsWith(stdPrefix): arg else: m)
+        conf.implicitImports.add m
   of "include":
     expectArg(conf, switch, arg, pass, info)
     if pass in {passCmd2, passPP}:
@@ -1026,7 +946,7 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
     expectArg(conf, switch, arg, pass, info)
     var value: int = 10_000_000
     discard parseSaturatedNatural(arg, value)
-    if value <= 0: localError(conf, info, "maxLoopIterationsVM must be a positive integer greater than zero")
+    if not value > 0: localError(conf, info, "maxLoopIterationsVM must be a positive integer greater than zero")
     conf.maxLoopIterationsVM = value
   of "maxcalldepthvm":
     expectArg(conf, switch, arg, pass, info)
@@ -1189,9 +1109,6 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
   of "shownonexports":
     expectNoArg(conf, switch, arg, pass, info)
     showNonExportedFields(conf)
-  of "raw":
-    expectNoArg(conf, switch, arg, pass, info)
-    docRawOutput(conf)
   of "exceptions":
     case arg.normalize
     of "cpp": conf.exc = excCpp
@@ -1223,10 +1140,9 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
       defineSymbol(conf.symbols, "nimSeqsV2")
   of "stylecheck":
     case arg.normalize
-    of "off": conf.globalOptions = conf.globalOptions - {optStyleHint, optStyleError, optStyleWarning}
-    of "hint": conf.globalOptions = conf.globalOptions + {optStyleHint} - {optStyleError, optStyleWarning}
-    of "warning": conf.globalOptions = conf.globalOptions + {optStyleWarning} - {optStyleHint, optStyleError}
-    of "error": conf.globalOptions = conf.globalOptions + {optStyleError} - {optStyleHint, optStyleWarning}
+    of "off": conf.globalOptions = conf.globalOptions - {optStyleHint, optStyleError}
+    of "hint": conf.globalOptions = conf.globalOptions + {optStyleHint} - {optStyleError}
+    of "error": conf.globalOptions = conf.globalOptions + {optStyleError}
     of "usages": conf.globalOptions.incl optStyleUsages
     else: localError(conf, info, errOffHintsError % arg)
   of "showallmismatches":

compiler/condsyms.nim

@@ -175,5 +175,3 @@ proc initDefines*(symbols: StringTableRef) =
   defineSymbol("nimHasSetLengthSeqUninitMagic")
   defineSymbol("nimHasPreviewDuplicateModuleError")
 
-  defineSymbol("nimHasImplicitRangeConversion")
-

compiler/dfa.nim

@@ -483,7 +483,7 @@ proc constructCfg*(s: PSym; body: PNode; root: PSym): ControlFlowGraph =
     gen(c, body)
     if root.kind == skResult:
       genImplicitReturn(c)
-  when defined(gcArc) or defined(gcOrc) or defined(gcAtomicArc) or defined(gcYrc):
+  when defined(gcArc) or defined(gcOrc) or defined(gcAtomicArc):
     result = c.code # will move
   else:
     shallowCopy(result, c.code)

compiler/docgen.nim

@@ -148,7 +148,7 @@ proc cmpDecimalsIgnoreCase(a, b: string): int =
         limitB = iB
       while limitA < aLen and isDigit(a[limitA]): inc limitA
       while limitB < bLen and isDigit(b[limitB]): inc limitB
-      var pos = max(limitA-iA, limitB-iB)
+      var pos = max(limitA-iA, limitB-iA)
       while pos > 0:
         if limitA-pos < iA:  # digit in `a` is 0 effectively
           result = ord('0') - ord(b[limitB-pos])
@@ -433,9 +433,6 @@ proc getVarIdx(varnames: openArray[string], id: string): int =
 
 proc genComment(d: PDoc, n: PNode): PRstNode =
   if n.comment.len > 0:
-    if optDocRaw in d.conf.globalOptions:
-      return newRstLeaf(n.comment)
-
     d.sharedState.currFileIdx = addRstFileIndex(d, n.info)
     try:
       result = parseRst(n.comment,
@@ -540,11 +537,10 @@ proc nodeToHighlightedHtml(d: PDoc; n: PNode; result: var string;
       elif s != nil and s.kind in {skType, skVar, skLet, skConst} and
            sfExported in s.flags and s.owner != nil and
            belongsToProjectPackage(d.conf, s.owner) and d.target == outHtml:
-        let href = (if d.module == s.owner: ""
-            else: externalDep(d, s.owner).changeFileExt("html")
-          ) & "#" & literal
-        result.addf "<a href=\"$1\"><span class=\"Identifier\">$2</span></a>",
-            [href, escLit]
+        let external = externalDep(d, s.owner)
+        result.addf "<a href=\"$1#$2\"><span class=\"Identifier\">$3</span></a>",
+          [changeFileExt(external, "html"), literal,
+           escLit]
       else:
         dispA(d.conf, result, "<span class=\"Identifier\">$1</span>",
               "\\spanIdentifier{$1}", [escLit])
@@ -1180,12 +1176,8 @@ proc genJsonItem(d: PDoc, n, nameNode: PNode, k: TSymKind, nonExports = false):
                    "col": %n.info.col}
   )
   if comm != nil:
-    if optDocRaw in d.conf.globalOptions:
-      result.json["description"] = %comm.text
-    else:
-      result.rst = comm
-      result.rstField = "description"
-
+    result.rst = comm
+    result.rstField = "description"
   if r.buf.len > 0:
     result.json["code"] = %r.buf
   if k in routineKinds:
@@ -1426,7 +1418,7 @@ proc generateDoc*(d: PDoc, n, orig: PNode, config: ConfigRef, docFlags: DocFlags
   of nkExportExceptStmt: discard "transformed into nkExportStmt by semExportExcept"
   of nkFromStmt, nkImportExceptStmt: traceDeps(d, n[0])
   of nkCallKinds:
-    var comm = default(ItemPre)
+    var comm: ItemPre = default(ItemPre)
     getAllRunnableExamples(d, n, comm)
     if comm.len != 0: d.modDescPre.add(comm)
   else: discard

compiler/enumtostr.nim

@@ -48,7 +48,6 @@ proc genEnumToStrProc*(t: PType; info: TLineInfo; g: ModuleGraph; idgen: IdGener
   n[resultPos] = newSymNode(res)
   result.ast = n
   incl result.flagsImpl, {sfFromGeneric, sfNeverRaises}
-  setHookDisamb(g, result, "$enumtostr", t)
 
 proc searchObjCaseImpl(obj: PNode; field: PSym): PNode =
   case obj.kind

compiler/guards.nim

@@ -46,7 +46,7 @@ proc isLocation(n: PNode): bool = not n.isValue
 
 proc isLet(n: PNode): bool =
   if n.kind == nkSym:
-    if n.sym.kind in {skLet, skConst, skTemp, skForVar}: # guard immutable variables
+    if n.sym.kind in {skLet, skTemp, skForVar}:
       result = true
     elif n.sym.kind == skParam and skipTypes(n.sym.typ,
                                              abstractInst).kind notin {tyVar}:

compiler/ic/bitabs.nim

@@ -0,0 +1,178 @@
+## A BiTable is a table that can be seen as an optimized pair
+## of `(Table[LitId, Val], Table[Val, LitId])`.
+
+import std/hashes
+import rodfiles
+
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+type
+  LitId* = distinct uint32
+
+  BiTable*[T] = object
+    vals: seq[T] # indexed by LitId
+    keys: seq[LitId]  # indexed by hash(val)
+
+proc initBiTable*[T](): BiTable[T] = BiTable[T](vals: @[], keys: @[])
+
+proc nextTry(h, maxHash: Hash): Hash {.inline.} =
+  result = (h + 1) and maxHash
+
+template maxHash(t): untyped = high(t.keys)
+template isFilled(x: LitId): bool = x.uint32 > 0'u32
+
+proc `$`*(x: LitId): string {.borrow.}
+proc `<`*(x, y: LitId): bool {.borrow.}
+proc `<=`*(x, y: LitId): bool {.borrow.}
+proc `==`*(x, y: LitId): bool {.borrow.}
+proc hash*(x: LitId): Hash {.borrow.}
+
+
+proc len*[T](t: BiTable[T]): int = t.vals.len
+
+proc mustRehash(length, counter: int): bool {.inline.} =
+  assert(length > counter)
+  result = (length * 2 < counter * 3) or (length - counter < 4)
+
+const
+  idStart = 1
+
+template idToIdx(x: LitId): int = x.int - idStart
+
+proc hasLitId*[T](t: BiTable[T]; x: LitId): bool =
+  let idx = idToIdx(x)
+  result = idx >= 0 and idx < t.vals.len
+
+proc enlarge[T](t: var BiTable[T]) =
+  var n: seq[LitId]
+  newSeq(n, len(t.keys) * 2)
+  swap(t.keys, n)
+  for i in 0..high(n):
+    let eh = n[i]
+    if isFilled(eh):
+      var j = hash(t.vals[idToIdx eh]) and maxHash(t)
+      while isFilled(t.keys[j]):
+        j = nextTry(j, maxHash(t))
+      t.keys[j] = move n[i]
+
+proc getKeyId*[T](t: BiTable[T]; v: T): LitId =
+  let origH = hash(v)
+  var h = origH and maxHash(t)
+  if t.keys.len != 0:
+    while true:
+      let litId = t.keys[h]
+      if not isFilled(litId): break
+      if t.vals[idToIdx t.keys[h]] == v: return litId
+      h = nextTry(h, maxHash(t))
+  return LitId(0)
+
+proc getOrIncl*[T](t: var BiTable[T]; v: T): LitId =
+  let origH = hash(v)
+  var h = origH and maxHash(t)
+  if t.keys.len != 0:
+    while true:
+      let litId = t.keys[h]
+      if not isFilled(litId): break
+      if t.vals[idToIdx t.keys[h]] == v: return litId
+      h = nextTry(h, maxHash(t))
+    # not found, we need to insert it:
+    if mustRehash(t.keys.len, t.vals.len):
+      enlarge(t)
+      # recompute where to insert:
+      h = origH and maxHash(t)
+      while true:
+        let litId = t.keys[h]
+        if not isFilled(litId): break
+        h = nextTry(h, maxHash(t))
+  else:
+    setLen(t.keys, 16)
+    h = origH and maxHash(t)
+
+  result = LitId(t.vals.len + idStart)
+  t.keys[h] = result
+  t.vals.add v
+
+
+proc `[]`*[T](t: var BiTable[T]; litId: LitId): var T {.inline.} =
+  let idx = idToIdx litId
+  assert idx < t.vals.len
+  result = t.vals[idx]
+
+proc `[]`*[T](t: BiTable[T]; litId: LitId): lent T {.inline.} =
+  let idx = idToIdx litId
+  assert idx < t.vals.len
+  result = t.vals[idx]
+
+proc hash*[T](t: BiTable[T]): Hash =
+  ## as the keys are hashes of the values, we simply use them instead
+  var h: Hash = 0
+  for i, n in pairs t.keys:
+    h = h !& hash((i, n))
+  result = !$h
+
+proc store*[T](f: var RodFile; t: BiTable[T]) =
+  storeSeq(f, t.vals)
+  storeSeq(f, t.keys)
+
+proc load*[T](f: var RodFile; t: var BiTable[T]) =
+  loadSeq(f, t.vals)
+  loadSeq(f, t.keys)
+
+proc sizeOnDisc*(t: BiTable[string]): int =
+  result = 4
+  for x in t.vals:
+    result += x.len + 4
+  result += t.keys.len * sizeof(LitId)
+
+when isMainModule:
+
+  var t: BiTable[string]
+
+  echo getOrIncl(t, "hello")
+
+  echo getOrIncl(t, "hello")
+  echo getOrIncl(t, "hello3")
+  echo getOrIncl(t, "hello4")
+  echo getOrIncl(t, "helloasfasdfdsa")
+  echo getOrIncl(t, "hello")
+  echo getKeyId(t, "hello")
+  echo getKeyId(t, "none")
+
+  for i in 0 ..< 100_000:
+    discard t.getOrIncl($i & "___" & $i)
+
+  for i in 0 ..< 100_000:
+    assert t.getOrIncl($i & "___" & $i).idToIdx == i + 4
+  echo "begin"
+  echo t.vals.len
+
+  echo t.vals[0]
+  echo t.vals[1004]
+
+  echo "middle"
+
+  var tf: BiTable[float]
+
+  discard tf.getOrIncl(0.4)
+  discard tf.getOrIncl(16.4)
+  discard tf.getOrIncl(32.4)
+  echo getKeyId(tf, 32.4)
+
+  var f2 = open("testblah.bin", fmWrite)
+  echo store(f2, tf)
+  f2.close
+
+  var f1 = open("testblah.bin", fmRead)
+
+  var t2: BiTable[float]
+
+  echo f1.load(t2)
+  echo t2.vals.len
+
+  echo getKeyId(t2, 32.4)
+
+  echo "end"
+
+
+  f1.close

compiler/ic/cbackend.nim

@@ -0,0 +1,179 @@
+#
+#
+#           The Nim Compiler
+#        (c) Copyright 2021 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+## New entry point into our C/C++ code generator. Ideally
+## somebody would rewrite the old backend (which is 8000 lines of crufty Nim code)
+## to work on packed trees directly and produce the C code as an AST which can
+## then be rendered to text in a very simple manner. Unfortunately nobody wrote
+## this code. So instead we wrap the existing cgen.nim and its friends so that
+## we call directly into the existing code generation logic but avoiding the
+## naive, outdated `passes` design. Thus you will see some
+## `useAliveDataFromDce in flags` checks in the old code -- the old code is
+## also doing cross-module dependency tracking and DCE that we don't need
+## anymore. DCE is now done as prepass over the entire packed module graph.
+
+import std/[packedsets, algorithm, tables]
+
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+import ".."/[ast, options, lineinfos, modulegraphs, cgendata, cgen,
+  pathutils, extccomp, msgs, modulepaths]
+
+import packed_ast, ic, dce, rodfiles
+
+proc unpackTree(g: ModuleGraph; thisModule: int;
+                tree: PackedTree; n: NodePos): PNode =
+  var decoder = initPackedDecoder(g.config, g.cache)
+  result = loadNodes(decoder, g.packed, thisModule, tree, n)
+
+proc setupBackendModule(g: ModuleGraph; m: var LoadedModule) =
+  if g.backend == nil:
+    g.backend = cgendata.newModuleList(g)
+  assert g.backend != nil
+  var bmod = cgen.newModule(BModuleList(g.backend), m.module, g.config, idgenFromLoadedModule(m))
+
+proc generateCodeForModule(g: ModuleGraph; m: var LoadedModule; alive: var AliveSyms) =
+  var bmod = BModuleList(g.backend).mods[m.module.position]
+  assert bmod != nil
+  bmod.flags.incl useAliveDataFromDce
+  bmod.alive = move alive[m.module.position]
+
+  for p in allNodes(m.fromDisk.topLevel):
+    let n = unpackTree(g, m.module.position, m.fromDisk.topLevel, p)
+    cgen.genTopLevelStmt(bmod, n)
+
+  finalCodegenActions(g, bmod, newNodeI(nkStmtList, m.module.info))
+  for disp in getDispatchers(g):
+    genProcLvl3(bmod, disp)
+  m.fromDisk.backendFlags = cgen.whichInitProcs(bmod)
+
+proc replayTypeInfo(g: ModuleGraph; m: var LoadedModule; origin: FileIndex) =
+  for x in mitems(m.fromDisk.emittedTypeInfo):
+    #echo "found type ", x, " for file ", int(origin)
+    g.emittedTypeInfo[x] = origin
+
+proc addFileToLink(config: ConfigRef; m: PSym) =
+  let filename = AbsoluteFile toFullPath(config, m.position.FileIndex)
+  let ext =
+      if config.backend == backendCpp: ".nim.cpp"
+      elif config.backend == backendObjc: ".nim.m"
+      else: ".nim.c"
+  let cfile = changeFileExt(completeCfilePath(config,
+                            mangleModuleName(config, filename).AbsoluteFile), ext)
+  let objFile = completeCfilePath(config, toObjFile(config, cfile))
+  if fileExists(objFile):
+    var cf = Cfile(nimname: m.name.s, cname: cfile,
+                   obj: objFile,
+                   flags: {CfileFlag.Cached})
+    addFileToCompile(config, cf)
+
+when defined(debugDce):
+  import os, std/packedsets
+
+proc storeAliveSymsImpl(asymFile: AbsoluteFile; s: seq[int32]) =
+  var f = rodfiles.create(asymFile.string)
+  f.storeHeader()
+  f.storeSection aliveSymsSection
+  f.storeSeq(s)
+  close f
+
+template prepare {.dirty.} =
+  let asymFile = toRodFile(config, AbsoluteFile toFullPath(config, position.FileIndex), ".alivesyms")
+  var s = newSeqOfCap[int32](alive[position].len)
+  for a in items(alive[position]): s.add int32(a)
+  sort(s)
+
+proc storeAliveSyms(config: ConfigRef; position: int; alive: AliveSyms) =
+  prepare()
+  storeAliveSymsImpl(asymFile, s)
+
+proc aliveSymsChanged(config: ConfigRef; position: int; alive: AliveSyms): bool =
+  prepare()
+  var f2 = rodfiles.open(asymFile.string)
+  f2.loadHeader()
+  f2.loadSection aliveSymsSection
+  var oldData: seq[int32] = @[]
+  f2.loadSeq(oldData)
+  f2.close
+  if f2.err == ok and oldData == s:
+    result = false
+  else:
+    when defined(debugDce):
+      let oldAsSet = toPackedSet[int32](oldData)
+      let newAsSet = toPackedSet[int32](s)
+      echo "set of live symbols changed ", asymFile.changeFileExt("rod"), " ", position, " ", f2.err
+      echo "in old but not in new ", oldAsSet.difference(newAsSet), " number of entries in old ", oldAsSet.len
+      echo "in new but not in old ", newAsSet.difference(oldAsSet), " number of entries in new ", newAsSet.len
+      #if execShellCmd(getAppFilename() & " rod " & quoteShell(asymFile.changeFileExt("rod"))) != 0:
+      #  echo "command failed"
+    result = true
+    storeAliveSymsImpl(asymFile, s)
+
+proc genPackedModule(g: ModuleGraph, i: int; alive: var AliveSyms) =
+  # case statement here to enforce exhaustive checks.
+  case g.packed[i].status
+  of undefined:
+    discard "nothing to do"
+  of loading, stored:
+    assert false
+  of storing, outdated:
+    storeAliveSyms(g.config, g.packed[i].module.position, alive)
+    generateCodeForModule(g, g.packed[i], alive)
+    closeRodFile(g, g.packed[i].module)
+  of loaded:
+    if g.packed[i].loadedButAliveSetChanged:
+      generateCodeForModule(g, g.packed[i], alive)
+    else:
+      addFileToLink(g.config, g.packed[i].module)
+      replayTypeInfo(g, g.packed[i], FileIndex(i))
+
+      if g.backend == nil:
+        g.backend = cgendata.newModuleList(g)
+      registerInitProcs(BModuleList(g.backend), g.packed[i].module, g.packed[i].fromDisk.backendFlags)
+
+proc generateCode*(g: ModuleGraph) =
+  ## The single entry point, generate C(++) code for the entire
+  ## Nim program aka `ModuleGraph`.
+  resetForBackend(g)
+  var alive = computeAliveSyms(g.packed, g.config)
+
+  when false:
+    for i in 0..<len(g.packed):
+      echo i, " is of status ", g.packed[i].status, " ", toFullPath(g.config, FileIndex(i))
+
+  # First pass: Setup all the backend modules for all the modules that have
+  # changed:
+  for i in 0..<len(g.packed):
+    # case statement here to enforce exhaustive checks.
+    case g.packed[i].status
+    of undefined:
+      discard "nothing to do"
+    of loading, stored:
+      assert false
+    of storing, outdated:
+      setupBackendModule(g, g.packed[i])
+    of loaded:
+      # Even though this module didn't change, DCE might trigger a change.
+      # Consider this case: Module A uses symbol S from B and B does not use
+      # S itself. A is then edited not to use S either. Thus we have to
+      # recompile B in order to remove S from the final result.
+      if aliveSymsChanged(g.config, g.packed[i].module.position, alive):
+        g.packed[i].loadedButAliveSetChanged = true
+        setupBackendModule(g, g.packed[i])
+
+  # Second pass: Code generation.
+  let mainModuleIdx = g.config.projectMainIdx2.int
+  # We need to generate the main module last, because only then
+  # all init procs have been registered:
+  for i in 0..<len(g.packed):
+    if i != mainModuleIdx:
+      genPackedModule(g, i, alive)
+  if mainModuleIdx >= 0:
+    genPackedModule(g, mainModuleIdx, alive)

compiler/ic/dce.nim

@@ -0,0 +1,169 @@
+#
+#
+#           The Nim Compiler
+#        (c) Copyright 2021 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+## Dead code elimination (=DCE) for IC.
+
+import std/[intsets, tables]
+
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+import ".." / [ast, options, lineinfos, types]
+
+import packed_ast, ic, bitabs
+
+type
+  AliveSyms* = seq[IntSet]
+  AliveContext* = object ## Purpose is to fill the 'alive' field.
+    stack: seq[(int, TOptions, NodePos)] ## A stack for marking symbols as alive.
+    decoder: PackedDecoder ## We need a PackedDecoder for module ID address translations.
+    thisModule: int  ## The module we're currently analysing for DCE.
+    alive: AliveSyms ## The final result of our computation.
+    options: TOptions
+    compilerProcs: Table[string, (int, int32)]
+
+proc isExportedToC(c: var AliveContext; g: PackedModuleGraph; symId: int32): bool =
+  ## "Exported to C" procs are special (these are marked with '.exportc') because these
+  ## must not be optimized away!
+  let symPtr = unsafeAddr g[c.thisModule].fromDisk.syms[symId]
+  let flags = symPtr.flags
+  # due to a bug/limitation in the lambda lifting, unused inner procs
+  # are not transformed correctly; issue (#411). However, the whole purpose here
+  # is to eliminate unused procs. So there is no special logic required for this case.
+  if sfCompileTime notin flags:
+    if ({sfExportc, sfCompilerProc} * flags != {}) or
+        (symPtr.kind == skMethod):
+      result = true
+    else:
+      result = false
+      # XXX: This used to be a condition to:
+      #  (sfExportc in prc.flags and lfExportLib in prc.loc.flags) or
+    if sfCompilerProc in flags:
+      c.compilerProcs[g[c.thisModule].fromDisk.strings[symPtr.name]] = (c.thisModule, symId)
+  else:
+    result = false
+
+template isNotGeneric(n: NodePos): bool = ithSon(tree, n, genericParamsPos).kind == nkEmpty
+
+proc followLater(c: var AliveContext; g: PackedModuleGraph; module: int; item: int32) =
+  ## Marks a symbol 'item' as used and later in 'followNow' the symbol's body will
+  ## be analysed.
+  if not c.alive[module].containsOrIncl(item):
+    var body = g[module].fromDisk.syms[item].ast
+    if body != emptyNodeId:
+      let opt = g[module].fromDisk.syms[item].options
+      if g[module].fromDisk.syms[item].kind in routineKinds:
+        body = NodeId ithSon(g[module].fromDisk.bodies, NodePos body, bodyPos)
+      c.stack.add((module, opt, NodePos(body)))
+
+    when false:
+      let nid = g[module].fromDisk.syms[item].name
+      if nid != LitId(0):
+        let name = g[module].fromDisk.strings[nid]
+        if name in ["nimFrame", "callDepthLimitReached"]:
+          echo "I was called! ", name, " body exists: ", body != emptyNodeId, " ", module, " ", item
+
+proc requestCompilerProc(c: var AliveContext; g: PackedModuleGraph; name: string) =
+  let (module, item) = c.compilerProcs[name]
+  followLater(c, g, module, item)
+
+proc loadTypeKind(t: PackedItemId; c: AliveContext; g: PackedModuleGraph; toSkip: set[TTypeKind]): TTypeKind =
+  template kind(t: ItemId): TTypeKind = g[t.module].fromDisk.types[t.item].kind
+
+  var t2 = translateId(t, g, c.thisModule, c.decoder.config)
+  result = t2.kind
+  while result in toSkip:
+    t2 = translateId(g[t2.module].fromDisk.types[t2.item].types[^1], g, t2.module, c.decoder.config)
+    result = t2.kind
+
+proc rangeCheckAnalysis(c: var AliveContext; g: PackedModuleGraph; tree: PackedTree; n: NodePos) =
+  ## Replicates the logic of `ccgexprs.genRangeChck`.
+  ## XXX Refactor so that the duplicated logic is avoided. However, for now it's not clear
+  ## the approach has enough merit.
+  var dest = loadTypeKind(n.typ, c, g, abstractVar)
+  if optRangeCheck notin c.options or dest in {tyUInt..tyUInt64}:
+    discard "no need to generate a check because it was disabled"
+  else:
+    let n0t = loadTypeKind(n.firstSon.typ, c, g, {})
+    if n0t in {tyUInt, tyUInt64}:
+      c.requestCompilerProc(g, "raiseRangeErrorNoArgs")
+    else:
+      let raiser =
+        case loadTypeKind(n.typ, c, g, abstractVarRange)
+        of tyUInt..tyUInt64, tyChar: "raiseRangeErrorU"
+        of tyFloat..tyFloat128: "raiseRangeErrorF"
+        else: "raiseRangeErrorI"
+      c.requestCompilerProc(g, raiser)
+
+proc aliveCode(c: var AliveContext; g: PackedModuleGraph; tree: PackedTree; n: NodePos) =
+  ## Marks the symbols we encounter when we traverse the AST at `tree[n]` as alive, unless
+  ## it is purely in a declarative context (type section etc.).
+  case n.kind
+  of nkNone..pred(nkSym), succ(nkSym)..nkNilLit:
+    discard "ignore non-sym atoms"
+  of nkSym:
+    # This symbol is alive and everything its body references.
+    followLater(c, g, c.thisModule, tree[n].soperand)
+  of nkModuleRef:
+    let (n1, n2) = sons2(tree, n)
+    assert n1.kind == nkNone
+    assert n2.kind == nkNone
+    let m = n1.litId
+    let item = tree[n2].soperand
+    let otherModule = toFileIndexCached(c.decoder, g, c.thisModule, m).int
+    followLater(c, g, otherModule, item)
+  of nkMacroDef, nkTemplateDef, nkTypeSection, nkTypeOfExpr,
+     nkCommentStmt, nkIncludeStmt,
+     nkImportStmt, nkImportExceptStmt, nkExportStmt, nkExportExceptStmt,
+     nkFromStmt, nkStaticStmt:
+    discard
+  of nkVarSection, nkLetSection, nkConstSection:
+    # XXX ignore the defining local variable name?
+    for son in sonsReadonly(tree, n):
+      aliveCode(c, g, tree, son)
+  of nkChckRangeF, nkChckRange64, nkChckRange:
+    rangeCheckAnalysis(c, g, tree, n)
+  of nkProcDef, nkConverterDef, nkMethodDef, nkFuncDef, nkIteratorDef:
+    if n.firstSon.kind == nkSym and isNotGeneric(n):
+      let item = tree[n.firstSon].soperand
+      if isExportedToC(c, g, item):
+        # This symbol is alive and everything its body references.
+        followLater(c, g, c.thisModule, item)
+  else:
+    for son in sonsReadonly(tree, n):
+      aliveCode(c, g, tree, son)
+
+proc followNow(c: var AliveContext; g: PackedModuleGraph) =
+  ## Mark all entries in the stack. Marking can add more entries
+  ## to the stack but eventually we have looked at every alive symbol.
+  while c.stack.len > 0:
+    let (modId, opt, ast) = c.stack.pop()
+    c.thisModule = modId
+    c.options = opt
+    aliveCode(c, g, g[modId].fromDisk.bodies, ast)
+
+proc computeAliveSyms*(g: PackedModuleGraph; conf: ConfigRef): AliveSyms =
+  ## Entry point for our DCE algorithm.
+  var c = AliveContext(stack: @[], decoder: PackedDecoder(config: conf),
+                       thisModule: -1, alive: newSeq[IntSet](g.len),
+                       options: conf.options)
+  for i in countdown(len(g)-1, 0):
+    if g[i].status != undefined:
+      c.thisModule = i
+      for p in allNodes(g[i].fromDisk.topLevel):
+        aliveCode(c, g, g[i].fromDisk.topLevel, p)
+
+  followNow(c, g)
+  result = move(c.alive)
+
+proc isAlive*(a: AliveSyms; module: int, item: int32): bool =
+  ## Backends use this to query if a symbol is `alive` which means
+  ## we need to produce (C/C++/etc) code for it.
+  result = a[module].contains(item)
+

compiler/ic/design.rst

@@ -0,0 +1,56 @@
+====================================
+  Incremental Recompilations
+====================================
+
+We split the Nim compiler into a frontend and a backend.
+The frontend produces a set of `.rod` files. Every `.nim` module
+produces its own `.rod` file.
+
+- The IR must be a faithful representation of the AST in memory.
+- The backend can do its own caching but doesn't have to. In the
+  current implementation the backend also caches its results.
+
+Advantage of the "set of files" vs the previous global database:
+- By construction, we either read from the `.rod` file or from the
+  `.nim` file, there can be no inconsistency. There can also be no
+  partial updates.
+- No dependency to external packages (SQLite). SQLite simply is too
+  slow and the old way of serialization was too slow too. We use a
+  format designed for Nim and expect to base further tools on this
+  file format.
+
+References to external modules must be (moduleId, symId) pairs.
+The symbol IDs are module specific. This way no global ID increment
+mechanism needs to be implemented that we could get wrong. ModuleIds
+are rod-file specific too.
+
+
+
+Global state
+------------
+
+There is no global state.
+
+Rod File Format
+---------------
+
+It's a simple binary file format. `rodfiles.nim` contains some details.
+
+
+Backend
+-------
+
+Nim programmers have to come to enjoy whole-program dead code elimination,
+by default. Since this is a "whole program" optimization, it does break
+modularity. However, thanks to the packed AST representation we can perform
+this global analysis without having to unpack anything. This is basically
+a mark&sweep GC algorithm:
+
+- Start with the top level statements. Every symbol that is referenced
+  from a top level statement is not "dead" and needs to be compiled by
+  the backend.
+- Every symbol referenced from a referenced symbol also has to be
+  compiled.
+
+Caching logic: Only if the set of alive symbols is different from the
+last run, the module has to be regenerated.

compiler/ic/iclineinfos.nim

@@ -0,0 +1,84 @@
+#
+#
+#           The Nim Compiler
+#        (c) Copyright 2024 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+# For the line information we use 32 bits. They are used as follows:
+# Bit 0 (AsideBit): If we have inline line information or not. If not, the
+# remaining 31 bits are used as an index into a seq[(LitId, int, int)].
+#
+# We use 10 bits for the "file ID", this means a program can consist of as much
+# as 1024 different files. (If it uses more files than that, the overflow bit
+# would be set.)
+# This means we have 21 bits left to encode the (line, col) pair. We use 7 bits for the column
+# so 128 is the limit and 14 bits for the line number.
+# The packed representation supports files with up to 16384 lines.
+# Keep in mind that whenever any limit is reached the AsideBit is set and the real line
+# information is kept in a side channel.
+
+import std / assertions
+
+const
+  AsideBit = 1
+  FileBits = 10
+  LineBits = 14
+  ColBits = 7
+  FileMax = (1 shl FileBits) - 1
+  LineMax = (1 shl LineBits) - 1
+  ColMax = (1 shl ColBits) - 1
+
+static:
+  assert AsideBit + FileBits + LineBits + ColBits == 32
+
+import .. / ic / [bitabs, rodfiles] # for LitId
+
+type
+  PackedLineInfo* = distinct uint32
+
+  LineInfoManager* = object
+    aside: seq[(LitId, int32, int32)]
+
+const
+  NoLineInfo* = PackedLineInfo(0'u32)
+
+proc pack*(m: var LineInfoManager; file: LitId; line, col: int32): PackedLineInfo =
+  if file.uint32 <= FileMax.uint32 and line <= LineMax and col <= ColMax:
+    let col = if col < 0'i32: 0'u32 else: col.uint32
+    let line = if line < 0'i32: 0'u32 else: line.uint32
+    # use inline representation:
+    result = PackedLineInfo((file.uint32 shl 1'u32) or (line shl uint32(AsideBit + FileBits)) or
+      (col shl uint32(AsideBit + FileBits + LineBits)))
+  else:
+    result = PackedLineInfo((m.aside.len shl 1) or AsideBit)
+    m.aside.add (file, line, col)
+
+proc unpack*(m: LineInfoManager; i: PackedLineInfo): (LitId, int32, int32) =
+  let i = i.uint32
+  if (i and 1'u32) == 0'u32:
+    # inline representation:
+    result = (LitId((i shr 1'u32) and FileMax.uint32),
+      int32((i shr uint32(AsideBit + FileBits)) and LineMax.uint32),
+      int32((i shr uint32(AsideBit + FileBits + LineBits)) and ColMax.uint32))
+  else:
+    result = m.aside[int(i shr 1'u32)]
+
+proc getFileId*(m: LineInfoManager; i: PackedLineInfo): LitId =
+  result = unpack(m, i)[0]
+
+proc store*(r: var RodFile; m: LineInfoManager) = storeSeq(r, m.aside)
+proc load*(r: var RodFile; m: var LineInfoManager) = loadSeq(r, m.aside)
+
+when isMainModule:
+  var m = LineInfoManager(aside: @[])
+  for i in 0'i32..<16388'i32:
+    for col in 0'i32..<100'i32:
+      let packed = pack(m, LitId(1023), i, col)
+      let u = unpack(m, packed)
+      assert u[0] == LitId(1023)
+      assert u[1] == i
+      assert u[2] == col
+  echo m.aside.len

compiler/ic/integrity.nim

@@ -0,0 +1,155 @@
+#
+#
+#           The Nim Compiler
+#        (c) Copyright 2021 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+## Integrity checking for a set of .rod files.
+## The set must cover a complete Nim project.
+
+import std/[sets, tables]
+
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+import ".." / [ast, modulegraphs]
+import packed_ast, bitabs, ic
+
+type
+  CheckedContext = object
+    g: ModuleGraph
+    thisModule: int32
+    checkedSyms: HashSet[ItemId]
+    checkedTypes: HashSet[ItemId]
+
+proc checkType(c: var CheckedContext; typeId: PackedItemId)
+proc checkForeignSym(c: var CheckedContext; symId: PackedItemId)
+proc checkNode(c: var CheckedContext; tree: PackedTree; n: NodePos)
+
+proc checkTypeObj(c: var CheckedContext; typ: PackedType) =
+  for child in typ.types:
+    checkType(c, child)
+  if typ.n != emptyNodeId:
+    checkNode(c, c.g.packed[c.thisModule].fromDisk.bodies, NodePos typ.n)
+  if typ.sym != nilItemId:
+    checkForeignSym(c, typ.sym)
+  if typ.owner != nilItemId:
+    checkForeignSym(c, typ.owner)
+  checkType(c, typ.typeInst)
+
+proc checkType(c: var CheckedContext; typeId: PackedItemId) =
+  if typeId == nilItemId: return
+  let itemId = translateId(typeId, c.g.packed, c.thisModule, c.g.config)
+  if not c.checkedTypes.containsOrIncl(itemId):
+    let oldThisModule = c.thisModule
+    c.thisModule = itemId.module
+    checkTypeObj c, c.g.packed[itemId.module].fromDisk.types[itemId.item]
+    c.thisModule = oldThisModule
+
+proc checkSym(c: var CheckedContext; s: PackedSym) =
+  if s.name != LitId(0):
+    assert c.g.packed[c.thisModule].fromDisk.strings.hasLitId s.name
+  checkType c, s.typ
+  if s.ast != emptyNodeId:
+    checkNode(c, c.g.packed[c.thisModule].fromDisk.bodies, NodePos s.ast)
+  if s.owner != nilItemId:
+    checkForeignSym(c, s.owner)
+
+proc checkLocalSym(c: var CheckedContext; item: int32) =
+  let itemId = ItemId(module: c.thisModule, item: item)
+  if not c.checkedSyms.containsOrIncl(itemId):
+    checkSym c, c.g.packed[c.thisModule].fromDisk.syms[item]
+
+proc checkForeignSym(c: var CheckedContext; symId: PackedItemId) =
+  let itemId = translateId(symId, c.g.packed, c.thisModule, c.g.config)
+  if not c.checkedSyms.containsOrIncl(itemId):
+    let oldThisModule = c.thisModule
+    c.thisModule = itemId.module
+    checkSym c, c.g.packed[itemId.module].fromDisk.syms[itemId.item]
+    c.thisModule = oldThisModule
+
+proc checkNode(c: var CheckedContext; tree: PackedTree; n: NodePos) =
+  let t = findType(tree, n)
+  if t != nilItemId:
+    checkType(c, t)
+  case n.kind
+  of nkEmpty, nkNilLit, nkType, nkNilRodNode:
+    discard
+  of nkIdent:
+    assert c.g.packed[c.thisModule].fromDisk.strings.hasLitId n.litId
+  of nkSym:
+    checkLocalSym(c, tree[n].soperand)
+  of directIntLit:
+    discard
+  of externIntLit, nkFloatLit..nkFloat128Lit:
+    assert c.g.packed[c.thisModule].fromDisk.numbers.hasLitId n.litId
+  of nkStrLit..nkTripleStrLit:
+    assert c.g.packed[c.thisModule].fromDisk.strings.hasLitId n.litId
+  of nkModuleRef:
+    let (n1, n2) = sons2(tree, n)
+    assert n1.kind == nkNone
+    assert n2.kind == nkNone
+    checkForeignSym(c, PackedItemId(module: n1.litId, item: tree[n2].soperand))
+  else:
+    for n0 in sonsReadonly(tree, n):
+      checkNode(c, tree, n0)
+
+proc checkTree(c: var CheckedContext; t: PackedTree) =
+  for p in allNodes(t): checkNode(c, t, p)
+
+proc checkLocalSymIds(c: var CheckedContext; m: PackedModule; symIds: seq[int32]) =
+  for symId in symIds:
+    assert symId >= 0 and symId < m.syms.len, $symId & " " & $m.syms.len
+
+proc checkModule(c: var CheckedContext; m: PackedModule) =
+  # We check that:
+  # - Every symbol references existing types and symbols.
+  # - Every tree node references existing types and symbols.
+  for _, v in pairs(m.syms):
+    checkLocalSym c, v.id
+
+  checkTree c, m.toReplay
+  checkTree c, m.topLevel
+
+  for e in m.exports:
+    #assert e[1] >= 0 and e[1] < m.syms.len
+    assert e[0] == m.syms[e[1]].name
+
+  for e in m.compilerProcs:
+    #assert e[1] >= 0 and e[1] < m.syms.len
+    assert e[0] == m.syms[e[1]].name
+
+  checkLocalSymIds c, m, m.converters
+  checkLocalSymIds c, m, m.methods
+  checkLocalSymIds c, m, m.trmacros
+  checkLocalSymIds c, m, m.pureEnums
+  #[
+    To do: Check all these fields:
+
+    reexports*: seq[(LitId, PackedItemId)]
+    macroUsages*: seq[(PackedItemId, PackedLineInfo)]
+
+    typeInstCache*: seq[(PackedItemId, PackedItemId)]
+    procInstCache*: seq[PackedInstantiation]
+    attachedOps*: seq[(TTypeAttachedOp, PackedItemId, PackedItemId)]
+    methodsPerGenericType*: seq[(PackedItemId, int, PackedItemId)]
+    enumToStringProcs*: seq[(PackedItemId, PackedItemId)]
+    methodsPerType*: seq[(PackedItemId, PackedItemId)]
+    dispatchers*: seq[PackedItemId]
+  ]#
+
+proc checkIntegrity*(g: ModuleGraph) =
+  var c = CheckedContext(g: g)
+  for i in 0..<len(g.packed):
+    # case statement here to enforce exhaustive checks.
+    case g.packed[i].status
+    of undefined:
+      discard "nothing to do"
+    of loading:
+      assert false, "cannot check integrity: Module still loading"
+    of stored, storing, outdated, loaded:
+      c.thisModule = int32 i
+      checkModule(c, g.packed[i].fromDisk)

compiler/ic/navigator.nim

@@ -0,0 +1,183 @@
+#
+#
+#           The Nim Compiler
+#        (c) Copyright 2021 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+## Supports the "nim check --ic:legacy --defusages:FILE,LINE,COL"
+## IDE-like features. It uses the set of .rod files to accomplish
+## its task. The set must cover a complete Nim project.
+
+import std/[sets, tables]
+
+from std/os import nil
+from std/private/miscdollars import toLocation
+
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+import ".." / [ast, modulegraphs, msgs, options]
+import iclineinfos
+import packed_ast, bitabs, ic
+
+type
+  UnpackedLineInfo = object
+    file: LitId
+    line, col: int
+  NavContext = object
+    g: ModuleGraph
+    thisModule: int32
+    trackPos: UnpackedLineInfo
+    alreadyEmitted: HashSet[string]
+    outputSep: char # for easier testing, use short filenames and spaces instead of tabs.
+
+proc isTracked(man: LineInfoManager; current: PackedLineInfo, trackPos: UnpackedLineInfo, tokenLen: int): bool =
+  let (currentFile, currentLine, currentCol) = man.unpack(current)
+  if currentFile == trackPos.file and currentLine == trackPos.line:
+    let col = trackPos.col
+    if col >= currentCol and col < currentCol+tokenLen:
+      result = true
+    else:
+      result = false
+  else:
+    result = false
+
+proc searchLocalSym(c: var NavContext; s: PackedSym; info: PackedLineInfo): bool =
+  result = s.name != LitId(0) and
+    isTracked(c.g.packed[c.thisModule].fromDisk.man, info, c.trackPos, c.g.packed[c.thisModule].fromDisk.strings[s.name].len)
+
+proc searchForeignSym(c: var NavContext; s: ItemId; info: PackedLineInfo): bool =
+  let name = c.g.packed[s.module].fromDisk.syms[s.item].name
+  result = name != LitId(0) and
+    isTracked(c.g.packed[c.thisModule].fromDisk.man, info, c.trackPos, c.g.packed[s.module].fromDisk.strings[name].len)
+
+const
+  EmptyItemId = ItemId(module: -1'i32, item: -1'i32)
+
+proc search(c: var NavContext; tree: PackedTree): ItemId =
+  # We use the linear representation here directly:
+  for i in 0..<len(tree):
+    let i = NodePos(i)
+    case tree[i].kind
+    of nkSym:
+      let item = tree[i].soperand
+      if searchLocalSym(c, c.g.packed[c.thisModule].fromDisk.syms[item], tree[i].info):
+        return ItemId(module: c.thisModule, item: item)
+    of nkModuleRef:
+      let (currentFile, currentLine, currentCol) = c.g.packed[c.thisModule].fromDisk.man.unpack(tree[i].info)
+      if currentLine == c.trackPos.line and currentFile == c.trackPos.file:
+        let (n1, n2) = sons2(tree, i)
+        assert n1.kind == nkInt32Lit
+        assert n2.kind == nkInt32Lit
+        let pId = PackedItemId(module: n1.litId, item: tree[n2].soperand)
+        let itemId = translateId(pId, c.g.packed, c.thisModule, c.g.config)
+        if searchForeignSym(c, itemId, tree[i].info):
+          return itemId
+    else: discard
+  return EmptyItemId
+
+proc isDecl(tree: PackedTree; n: NodePos): bool =
+  # XXX This is not correct yet.
+  const declarativeNodes = procDefs + {nkMacroDef, nkTemplateDef,
+    nkLetSection, nkVarSection, nkUsingStmt, nkConstSection, nkTypeSection,
+    nkIdentDefs, nkEnumTy, nkVarTuple}
+  result = n.int >= 0 and tree[n].kind in declarativeNodes
+
+proc usage(c: var NavContext; info: PackedLineInfo; isDecl: bool) =
+  let (fileId, line, col) = unpack(c.g.packed[c.thisModule].fromDisk.man, info)
+  var m = ""
+  var file = c.g.packed[c.thisModule].fromDisk.strings[fileId]
+  if c.outputSep == ' ':
+    file = os.extractFilename file
+  toLocation(m, file, line, col + ColOffset)
+  if not c.alreadyEmitted.containsOrIncl(m):
+    msgWriteln c.g.config, (if isDecl: "def" else: "usage") & c.outputSep & m
+
+proc list(c: var NavContext; tree: PackedTree; sym: ItemId) =
+  for i in 0..<len(tree):
+    let i = NodePos(i)
+    case tree[i].kind
+    of nkSym:
+      let item = tree[i].soperand
+      if sym.item == item and sym.module == c.thisModule:
+        usage(c, tree[i].info, isDecl(tree, parent(i)))
+    of nkModuleRef:
+      let (n1, n2) = sons2(tree, i)
+      assert n1.kind == nkNone
+      assert n2.kind == nkNone
+      let pId = PackedItemId(module: n1.litId, item: tree[n2].soperand)
+      let itemId = translateId(pId, c.g.packed, c.thisModule, c.g.config)
+      if itemId.item == sym.item and sym.module == itemId.module:
+        usage(c, tree[i].info, isDecl(tree, parent(i)))
+    else: discard
+
+proc searchForIncludeFile(g: ModuleGraph; fullPath: string): int =
+  for i in 0..<len(g.packed):
+    for k in 1..high(g.packed[i].fromDisk.includes):
+      # we start from 1 because the first "include" file is
+      # the module's filename.
+      if os.cmpPaths(g.packed[i].fromDisk.strings[g.packed[i].fromDisk.includes[k][0]], fullPath) == 0:
+        return i
+  return -1
+
+proc nav(g: ModuleGraph) =
+  # translate the track position to a packed position:
+  let unpacked = g.config.m.trackPos
+  var mid = unpacked.fileIndex.int
+
+  let fullPath = toFullPath(g.config, unpacked.fileIndex)
+
+  if g.packed[mid].status == undefined:
+    # check if 'mid' is an include file of some other module:
+    mid = searchForIncludeFile(g, fullPath)
+
+  if mid < 0:
+    localError(g.config, unpacked, "unknown file name: " & fullPath)
+    return
+
+  let fileId = g.packed[mid].fromDisk.strings.getKeyId(fullPath)
+
+  if fileId == LitId(0):
+    internalError(g.config, unpacked, "cannot find a valid file ID")
+    return
+
+  var c = NavContext(
+    g: g,
+    thisModule: int32 mid,
+    trackPos: UnpackedLineInfo(line: unpacked.line.int, col: unpacked.col.int, file: fileId),
+    outputSep: if isDefined(g.config, "nimIcNavigatorTests"): ' ' else: '\t'
+  )
+  var symId = search(c, g.packed[mid].fromDisk.topLevel)
+  if symId == EmptyItemId:
+    symId = search(c, g.packed[mid].fromDisk.bodies)
+
+  if symId == EmptyItemId:
+    localError(g.config, unpacked, "no symbol at this position")
+    return
+
+  for i in 0..<len(g.packed):
+    # case statement here to enforce exhaustive checks.
+    case g.packed[i].status
+    of undefined:
+      discard "nothing to do"
+    of loading:
+      assert false, "cannot check integrity: Module still loading"
+    of stored, storing, outdated, loaded:
+      c.thisModule = int32 i
+      list(c, g.packed[i].fromDisk.topLevel, symId)
+      list(c, g.packed[i].fromDisk.bodies, symId)
+
+proc navDefinition*(g: ModuleGraph) = nav(g)
+proc navUsages*(g: ModuleGraph) = nav(g)
+proc navDefusages*(g: ModuleGraph) = nav(g)
+
+proc writeRodFiles*(g: ModuleGraph) =
+  for i in 0..<len(g.packed):
+    case g.packed[i].status
+    of undefined, loading, stored, loaded:
+      discard "nothing to do"
+    of storing, outdated:
+      closeRodFile(g, g.packed[i].module)

compiler/ic/packed_ast.nim

@@ -0,0 +1,367 @@
+#
+#
+#           The Nim Compiler
+#        (c) Copyright 2020 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+## Packed AST representation, mostly based on a seq of nodes.
+## For IC support. Far future: Rewrite the compiler passes to
+## use this representation directly in all the transformations,
+## it is superior.
+
+import std/[hashes, tables, strtabs]
+import bitabs, rodfiles
+import ".." / [ast, options]
+
+import iclineinfos
+
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+type
+  SymId* = distinct int32
+  ModuleId* = distinct int32
+  NodePos* = distinct int
+
+  NodeId* = distinct int32
+
+  PackedItemId* = object
+    module*: LitId       # 0 if it's this module
+    item*: int32         # same as the in-memory representation
+
+const
+  nilItemId* = PackedItemId(module: LitId(0), item: 0.int32)
+
+const
+  emptyNodeId* = NodeId(-1)
+
+type
+  PackedLib* = object
+    kind*: TLibKind
+    generated*: bool
+    isOverridden*: bool
+    name*: LitId
+    path*: NodeId
+
+  PackedSym* = object
+    id*: int32
+    kind*: TSymKind
+    name*: LitId
+    typ*: PackedItemId
+    flags*: TSymFlags
+    magic*: TMagic
+    info*: PackedLineInfo
+    ast*: NodeId
+    owner*: PackedItemId
+    guard*: PackedItemId
+    bitsize*: int
+    alignment*: int # for alignment
+    options*: TOptions
+    position*: int
+    offset*: int32
+    disamb*: int32
+    externalName*: LitId # instead of TLoc
+    locFlags*: TLocFlags
+    annex*: PackedLib
+    when hasFFI:
+      cname*: LitId
+    constraint*: NodeId
+    instantiatedFrom*: PackedItemId
+
+  PackedType* = object
+    id*: int32
+    kind*: TTypeKind
+    callConv*: TCallingConvention
+    #nodekind*: TNodeKind
+    flags*: TTypeFlags
+    types*: seq[PackedItemId]
+    n*: NodeId
+    #nodeflags*: TNodeFlags
+    sym*: PackedItemId
+    owner*: PackedItemId
+    size*: BiggestInt
+    align*: int16
+    paddingAtEnd*: int16
+    # not serialized: loc*: TLoc because it is backend-specific
+    typeInst*: PackedItemId
+    nonUniqueId*: int32
+
+  PackedNode* = object     # 8 bytes
+    x: uint32
+    info*: PackedLineInfo
+
+  PackedTree* = object ## usually represents a full Nim module
+    nodes: seq[PackedNode]
+    withFlags: seq[(int32, TNodeFlags)]
+    withTypes: seq[(int32, PackedItemId)]
+
+  PackedInstantiation* = object
+    key*, sym*: PackedItemId
+    concreteTypes*: seq[PackedItemId]
+
+const
+  NodeKindBits = 8'u32
+  NodeKindMask = (1'u32 shl NodeKindBits) - 1'u32
+
+template kind*(n: PackedNode): TNodeKind = TNodeKind(n.x and NodeKindMask)
+template uoperand*(n: PackedNode): uint32 = (n.x shr NodeKindBits)
+template soperand*(n: PackedNode): int32 = int32(uoperand(n))
+
+template toX(k: TNodeKind; operand: uint32): uint32 =
+  uint32(k) or (operand shl NodeKindBits)
+
+template toX(k: TNodeKind; operand: LitId): uint32 =
+  uint32(k) or (operand.uint32 shl NodeKindBits)
+
+template typeId*(n: PackedNode): PackedItemId = n.typ
+
+proc `==`*(a, b: SymId): bool {.borrow.}
+proc hash*(a: SymId): Hash {.borrow.}
+
+proc `==`*(a, b: NodePos): bool {.borrow.}
+#proc `==`*(a, b: PackedItemId): bool {.borrow.}
+proc `==`*(a, b: NodeId): bool {.borrow.}
+
+proc newTreeFrom*(old: PackedTree): PackedTree =
+  result = PackedTree(nodes: @[])
+  when false: result.sh = old.sh
+
+proc addIdent*(tree: var PackedTree; s: LitId; info: PackedLineInfo) =
+  tree.nodes.add PackedNode(x: toX(nkIdent, uint32(s)), info: info)
+
+proc addSym*(tree: var PackedTree; s: int32; info: PackedLineInfo) =
+  tree.nodes.add PackedNode(x: toX(nkSym, cast[uint32](s)), info: info)
+
+proc addSymDef*(tree: var PackedTree; s: SymId; info: PackedLineInfo) =
+  tree.nodes.add PackedNode(x: toX(nkSym, cast[uint32](s)), info: info)
+
+proc isAtom*(tree: PackedTree; pos: int): bool {.inline.} = tree.nodes[pos].kind <= nkNilLit
+
+type
+  PatchPos = distinct int
+
+proc addNode*(t: var PackedTree; kind: TNodeKind; operand: int32;
+              typeId: PackedItemId = nilItemId; info: PackedLineInfo;
+              flags: TNodeFlags = {}) =
+  t.nodes.add PackedNode(x: toX(kind, cast[uint32](operand)), info: info)
+  if flags != {}:
+    t.withFlags.add (t.nodes.len.int32 - 1, flags)
+  if typeId != nilItemId:
+    t.withTypes.add (t.nodes.len.int32 - 1, typeId)
+
+proc prepare*(tree: var PackedTree; kind: TNodeKind; flags: TNodeFlags; typeId: PackedItemId; info: PackedLineInfo): PatchPos =
+  result = PatchPos tree.nodes.len
+  tree.addNode(kind = kind, flags = flags, operand = 0, info = info, typeId = typeId)
+
+proc prepare*(dest: var PackedTree; source: PackedTree; sourcePos: NodePos): PatchPos =
+  result = PatchPos dest.nodes.len
+  dest.nodes.add source.nodes[sourcePos.int]
+
+proc patch*(tree: var PackedTree; pos: PatchPos) =
+  let pos = pos.int
+  let k = tree.nodes[pos].kind
+  assert k > nkNilLit
+  let distance = int32(tree.nodes.len - pos)
+  assert distance > 0
+  tree.nodes[pos].x = toX(k, cast[uint32](distance))
+
+proc len*(tree: PackedTree): int {.inline.} = tree.nodes.len
+
+proc `[]`*(tree: PackedTree; i: NodePos): lent PackedNode {.inline.} =
+  tree.nodes[i.int]
+
+template rawSpan(n: PackedNode): int = int(uoperand(n))
+
+proc nextChild(tree: PackedTree; pos: var int) {.inline.} =
+  if tree.nodes[pos].kind > nkNilLit:
+    assert tree.nodes[pos].uoperand > 0
+    inc pos, tree.nodes[pos].rawSpan
+  else:
+    inc pos
+
+iterator sonsReadonly*(tree: PackedTree; n: NodePos): NodePos =
+  var pos = n.int
+  assert tree.nodes[pos].kind > nkNilLit
+  let last = pos + tree.nodes[pos].rawSpan
+  inc pos
+  while pos < last:
+    yield NodePos pos
+    nextChild tree, pos
+
+iterator sons*(dest: var PackedTree; tree: PackedTree; n: NodePos): NodePos =
+  let patchPos = prepare(dest, tree, n)
+  for x in sonsReadonly(tree, n): yield x
+  patch dest, patchPos
+
+iterator isons*(dest: var PackedTree; tree: PackedTree;
+                n: NodePos): (int, NodePos) =
+  var i = 0
+  for ch0 in sons(dest, tree, n):
+    yield (i, ch0)
+    inc i
+
+iterator sonsFrom1*(tree: PackedTree; n: NodePos): NodePos =
+  var pos = n.int
+  assert tree.nodes[pos].kind > nkNilLit
+  let last = pos + tree.nodes[pos].rawSpan
+  inc pos
+  if pos < last:
+    nextChild tree, pos
+  while pos < last:
+    yield NodePos pos
+    nextChild tree, pos
+
+iterator sonsWithoutLast2*(tree: PackedTree; n: NodePos): NodePos =
+  var count = 0
+  for child in sonsReadonly(tree, n):
+    inc count
+  var pos = n.int
+  assert tree.nodes[pos].kind > nkNilLit
+  let last = pos + tree.nodes[pos].rawSpan
+  inc pos
+  while pos < last and count > 2:
+    yield NodePos pos
+    dec count
+    nextChild tree, pos
+
+proc parentImpl(tree: PackedTree; n: NodePos): NodePos =
+  # finding the parent of a node is rather easy:
+  var pos = n.int - 1
+  while pos >= 0 and (isAtom(tree, pos) or (pos + tree.nodes[pos].rawSpan - 1 < n.int)):
+    dec pos
+  #assert pos >= 0, "node has no parent"
+  result = NodePos(pos)
+
+template parent*(n: NodePos): NodePos = parentImpl(tree, n)
+
+proc hasXsons*(tree: PackedTree; n: NodePos; x: int): bool =
+  var count = 0
+  if tree.nodes[n.int].kind > nkNilLit:
+    for child in sonsReadonly(tree, n): inc count
+  result = count == x
+
+proc hasAtLeastXsons*(tree: PackedTree; n: NodePos; x: int): bool =
+  if tree.nodes[n.int].kind > nkNilLit:
+    var count = 0
+    for child in sonsReadonly(tree, n):
+      inc count
+      if count >= x: return true
+  return false
+
+proc firstSon*(tree: PackedTree; n: NodePos): NodePos {.inline.} =
+  NodePos(n.int+1)
+proc kind*(tree: PackedTree; n: NodePos): TNodeKind {.inline.} =
+  tree.nodes[n.int].kind
+proc litId*(tree: PackedTree; n: NodePos): LitId {.inline.} =
+  LitId tree.nodes[n.int].uoperand
+proc info*(tree: PackedTree; n: NodePos): PackedLineInfo {.inline.} =
+  tree.nodes[n.int].info
+
+proc findType*(tree: PackedTree; n: NodePos): PackedItemId =
+  for x in tree.withTypes:
+    if x[0] == int32(n): return x[1]
+    if x[0] > int32(n): return nilItemId
+  return nilItemId
+
+proc findFlags*(tree: PackedTree; n: NodePos): TNodeFlags =
+  for x in tree.withFlags:
+    if x[0] == int32(n): return x[1]
+    if x[0] > int32(n): return {}
+  return {}
+
+template typ*(n: NodePos): PackedItemId =
+  tree.findType(n)
+template flags*(n: NodePos): TNodeFlags =
+  tree.findFlags(n)
+
+template uoperand*(n: NodePos): uint32 =
+  tree.nodes[n.int].uoperand
+
+proc span*(tree: PackedTree; pos: int): int {.inline.} =
+  if isAtom(tree, pos): 1 else: tree.nodes[pos].rawSpan
+
+proc sons2*(tree: PackedTree; n: NodePos): (NodePos, NodePos) =
+  assert(not isAtom(tree, n.int))
+  let a = n.int+1
+  let b = a + span(tree, a)
+  result = (NodePos a, NodePos b)
+
+proc sons3*(tree: PackedTree; n: NodePos): (NodePos, NodePos, NodePos) =
+  assert(not isAtom(tree, n.int))
+  let a = n.int+1
+  let b = a + span(tree, a)
+  let c = b + span(tree, b)
+  result = (NodePos a, NodePos b, NodePos c)
+
+proc ithSon*(tree: PackedTree; n: NodePos; i: int): NodePos =
+  result = default(NodePos)
+  if tree.nodes[n.int].kind > nkNilLit:
+    var count = 0
+    for child in sonsReadonly(tree, n):
+      if count == i: return child
+      inc count
+  assert false, "node has no i-th child"
+
+when false:
+  proc `@`*(tree: PackedTree; lit: LitId): lent string {.inline.} =
+    tree.sh.strings[lit]
+
+template kind*(n: NodePos): TNodeKind = tree.nodes[n.int].kind
+template info*(n: NodePos): PackedLineInfo = tree.nodes[n.int].info
+template litId*(n: NodePos): LitId = LitId tree.nodes[n.int].uoperand
+
+template symId*(n: NodePos): SymId = SymId tree.nodes[n.int].soperand
+
+proc firstSon*(n: NodePos): NodePos {.inline.} = NodePos(n.int+1)
+
+const
+  externIntLit* = {nkCharLit,
+    nkIntLit,
+    nkInt8Lit,
+    nkInt16Lit,
+    nkInt32Lit,
+    nkInt64Lit,
+    nkUIntLit,
+    nkUInt8Lit,
+    nkUInt16Lit,
+    nkUInt32Lit,
+    nkUInt64Lit}
+
+  externSIntLit* = {nkIntLit, nkInt8Lit, nkInt16Lit, nkInt32Lit, nkInt64Lit}
+  externUIntLit* = {nkUIntLit, nkUInt8Lit, nkUInt16Lit, nkUInt32Lit, nkUInt64Lit}
+  directIntLit* = nkNone
+
+template copyInto*(dest, n, body) =
+  let patchPos = prepare(dest, tree, n)
+  body
+  patch dest, patchPos
+
+template copyIntoKind*(dest, kind, info, body) =
+  let patchPos = prepare(dest, kind, info)
+  body
+  patch dest, patchPos
+
+proc getNodeId*(tree: PackedTree): NodeId {.inline.} = NodeId tree.nodes.len
+
+iterator allNodes*(tree: PackedTree): NodePos =
+  var p = 0
+  while p < tree.len:
+    yield NodePos(p)
+    let s = span(tree, p)
+    inc p, s
+
+proc toPackedItemId*(item: int32): PackedItemId {.inline.} =
+  PackedItemId(module: LitId(0), item: item)
+
+proc load*(f: var RodFile; t: var PackedTree) =
+  loadSeq f, t.nodes
+  loadSeq f, t.withFlags
+  loadSeq f, t.withTypes
+
+proc store*(f: var RodFile; t: PackedTree) =
+  storeSeq f, t.nodes
+  storeSeq f, t.withFlags
+  storeSeq f, t.withTypes

compiler/ic/replayer.nim

@@ -19,11 +19,10 @@ import std/tables
 when defined(nimPreviewSlimSystem):
   import std/assertions
 
-proc replayStateChanges*(module: PSym; g: ModuleGraph; list: PNode) =
-  ## `list` is an `nkStmtList` of `nkReplayAction` nodes (macro-cache puts/incs/
-  ## adds/incls and a few pragmas) recorded for `module`. Under the NIF backend a
-  ## loaded module's `ast` is never reconstructed, so the caller passes the replay
-  ## actions it parsed out of the module's NIF directly.
+import packed_ast, ic, bitabs
+
+proc replayStateChanges*(module: PSym; g: ModuleGraph) =
+  let list = module.ast
   assert list != nil
   assert list.kind == nkStmtList
   for n in list:
@@ -67,9 +66,8 @@ proc replayStateChanges*(module: PSym; g: ModuleGraph; list: PNode) =
           g.cacheTables[destKey] = initBTree[string, PNode]()
         if not contains(g.cacheTables[destKey], key):
           g.cacheTables[destKey].add(key, val)
-        # else: the same key was already replayed. Under IC the import closure is
-        # replayed (direct module + transitive deps), so the same registration can
-        # legitimately be reached twice; re-applying it is a no-op, not an error.
+        else:
+          internalError(g.config, n.info, "key already exists: " & key)
       of "incl":
         let destKey = n[1].strVal
         let val = n[2]
@@ -91,36 +89,83 @@ proc replayStateChanges*(module: PSym; g: ModuleGraph; list: PNode) =
       else:
         internalAssert g.config, false
 
-proc replayBackendActions*(g: ModuleGraph; module: PSym; list: PNode) =
-  ## Applies the backend-relevant replay actions (C compile/link directives)
-  ## found in a NIF-loaded module's top-level statement list. The `nifc`
-  ## backend loads modules without going through sem's `replayStateChanges`,
-  ## so e.g. math's `{.passL: "-lm".}` was lost and the final link failed
-  ## with undefined references. VM cache actions are deliberately NOT
-  ## replayed here — codegen does not run macros.
-  if list == nil: return
-  for n in list:
-    if n.kind == nkReplayAction and n.len >= 2 and
-        n[0].kind == nkStrLit and n[1].kind == nkStrLit:
-      case n[0].strVal
-      of "compile":
-        if n.len == 4 and n[2].kind == nkStrLit:
-          let cname = AbsoluteFile n[1].strVal
-          var cf = Cfile(nimname: splitFile(cname).name, cname: cname,
-                         obj: AbsoluteFile n[2].strVal,
-                         flags: {CfileFlag.External},
-                         customArgs: n[3].strVal)
-          extccomp.addExternalFileToCompile(g.config, cf)
-      of "link":
-        extccomp.addExternalFileToLink(g.config, AbsoluteFile n[1].strVal)
-      of "passl":
-        extccomp.addLinkOption(g.config, n[1].strVal)
-      of "passc":
-        extccomp.addCompileOption(g.config, n[1].strVal)
-      of "localpassc":
-        extccomp.addLocalCompileOption(g.config, n[1].strVal,
-          toFullPathConsiderDirty(g.config, module.info.fileIndex))
-      of "cppdefine":
-        options.cppDefine(g.config, n[1].strVal)
-      else:
-        discard
+proc replayBackendProcs*(g: ModuleGraph; module: int) =
+  for it in mitems(g.packed[module].fromDisk.attachedOps):
+    let key = translateId(it[0], g.packed, module, g.config)
+    let op = it[1]
+    let tmp = translateId(it[2], g.packed, module, g.config)
+    let symId = FullId(module: tmp.module, packed: it[2])
+    g.attachedOps[op][key] = LazySym(id: symId, sym: nil)
+
+  for it in mitems(g.packed[module].fromDisk.enumToStringProcs):
+    let key = translateId(it[0], g.packed, module, g.config)
+    let tmp = translateId(it[1], g.packed, module, g.config)
+    let symId = FullId(module: tmp.module, packed: it[1])
+    g.enumToStringProcs[key] = LazySym(id: symId, sym: nil)
+
+  for it in mitems(g.packed[module].fromDisk.methodsPerType):
+    let key = translateId(it[0], g.packed, module, g.config)
+    let tmp = translateId(it[1], g.packed, module, g.config)
+    let symId = FullId(module: tmp.module, packed: it[1])
+    g.methodsPerType.mgetOrPut(key, @[]).add LazySym(id: symId, sym: nil)
+
+  for it in mitems(g.packed[module].fromDisk.dispatchers):
+    let tmp = translateId(it, g.packed, module, g.config)
+    let symId = FullId(module: tmp.module, packed: it)
+    g.dispatchers.add LazySym(id: symId, sym: nil)
+
+proc replayGenericCacheInformation*(g: ModuleGraph; module: int) =
+  ## We remember the generic instantiations a module performed
+  ## in order to to avoid the code bloat that generic code tends
+  ## to imply. This is cheaper than deduplication of identical
+  ## generic instantiations. However, deduplication is more
+  ## powerful and general and I hope to implement it soon too
+  ## (famous last words).
+  assert g.packed[module].status == loaded
+  for it in g.packed[module].fromDisk.typeInstCache:
+    let key = translateId(it[0], g.packed, module, g.config)
+    g.typeInstCache.mgetOrPut(key, @[]).add LazyType(id: FullId(module: module, packed: it[1]), typ: nil)
+
+  for it in mitems(g.packed[module].fromDisk.procInstCache):
+    let key = translateId(it.key, g.packed, module, g.config)
+    let sym = translateId(it.sym, g.packed, module, g.config)
+    var concreteTypes = newSeq[FullId](it.concreteTypes.len)
+    for i in 0..high(it.concreteTypes):
+      let tmp = translateId(it.concreteTypes[i], g.packed, module, g.config)
+      concreteTypes[i] = FullId(module: tmp.module, packed: it.concreteTypes[i])
+
+    g.procInstCache.mgetOrPut(key, @[]).add LazyInstantiation(
+      module: module, sym: FullId(module: sym.module, packed: it.sym),
+      concreteTypes: concreteTypes, inst: nil)
+
+  for it in mitems(g.packed[module].fromDisk.methodsPerGenericType):
+    let key = translateId(it[0], g.packed, module, g.config)
+    let col = it[1]
+    let tmp = translateId(it[2], g.packed, module, g.config)
+    let symId = FullId(module: tmp.module, packed: it[2])
+    g.methodsPerGenericType.mgetOrPut(key, @[]).add (col, LazySym(id: symId, sym: nil))
+
+  replayBackendProcs(g, module)
+
+  for it in mitems(g.packed[module].fromDisk.methods):
+    let sym = loadSymFromId(g.config, g.cache, g.packed, module,
+                            PackedItemId(module: LitId(0), item: it))
+    methodDef(g, g.idgen, sym)
+
+  when false:
+    # not used anymore:
+    for it in mitems(g.packed[module].fromDisk.compilerProcs):
+      let symId = FullId(module: module, packed: PackedItemId(module: LitId(0), item: it[1]))
+      g.lazyCompilerprocs[g.packed[module].fromDisk.sh.strings[it[0]]] = symId
+
+  for it in mitems(g.packed[module].fromDisk.converters):
+    let symId = FullId(module: module, packed: PackedItemId(module: LitId(0), item: it))
+    g.ifaces[module].converters.add LazySym(id: symId, sym: nil)
+
+  for it in mitems(g.packed[module].fromDisk.trmacros):
+    let symId = FullId(module: module, packed: PackedItemId(module: LitId(0), item: it))
+    g.ifaces[module].patterns.add LazySym(id: symId, sym: nil)
+
+  for it in mitems(g.packed[module].fromDisk.pureEnums):
+    let symId = FullId(module: module, packed: PackedItemId(module: LitId(0), item: it))
+    g.ifaces[module].pureEnums.add LazySym(id: symId, sym: nil)

compiler/ic/rodfiles.nim

@@ -0,0 +1,283 @@
+#
+#
+#           The Nim Compiler
+#        (c) Copyright 2020 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+## Low level binary format used by the compiler to store and load various AST
+## and related data.
+##
+## NB: this is incredibly low level and if you're interested in how the
+##     compiler works and less a storage format, you're probably looking for
+##     the `ic` or `packed_ast` modules to understand the logical format.
+
+from std/typetraits import supportsCopyMem
+
+when defined(nimPreviewSlimSystem):
+  import std/[syncio, assertions]
+
+import std / tables
+
+## Overview
+## ========
+## `RodFile` represents a Rod File (versioned binary format), and the
+## associated data for common interactions such as IO and error tracking
+## (`RodFileError`). The file format broken up into sections (`RodSection`)
+## and preceded by a header (see: `cookie`). The precise layout, section
+## ordering and data following the section are determined by the user. See
+## `ic.loadRodFile`.
+##
+## A basic but "wrong" example of the lifecycle:
+## ---------------------------------------------
+## 1. `create` or `open`        - create a new one or open an existing
+## 2. `storeHeader`             - header info
+## 3. `storePrim` or `storeSeq` - save your stuff
+## 4. `close`                   - and we're done
+##
+## Now read the bits below to understand what's missing.
+##
+## ### Issues with the Example
+## Missing Sections:
+## This is a low level API, so headers and sections need to be stored and
+## loaded by the user, see `storeHeader` & `loadHeader` and `storeSection` &
+## `loadSection`, respectively.
+##
+## No Error Handling:
+## The API is centered around IO and prone to error, each operation checks or
+## sets the `RodFile.err` field. A user of this API needs to handle these
+## appropriately.
+##
+## API Notes
+## =========
+##
+## Valid inputs for Rod files
+## --------------------------
+## ASTs, hopes, dreams, and anything as long as it and any children it may have
+## support `copyMem`. This means anything that is not a pointer and that does not contain a pointer. At a glance these are:
+## * string
+## * objects & tuples (fields are recursed)
+## * sequences AKA `seq[T]`
+##
+## Note on error handling style
+## ----------------------------
+## A flag based approach is used where operations no-op in case of a
+## preexisting error and set the flag if they encounter one.
+##
+## Misc
+## ----
+## * 'Prim' is short for 'primitive', as in a non-sequence type
+
+type
+  RodSection* = enum
+    versionSection
+    configSection
+    stringsSection
+    checkSumsSection
+    depsSection
+    numbersSection
+    exportsSection
+    hiddenSection
+    reexportsSection
+    compilerProcsSection
+    trmacrosSection
+    convertersSection
+    methodsSection
+    pureEnumsSection
+    toReplaySection
+    topLevelSection
+    bodiesSection
+    symsSection
+    typesSection
+    typeInstCacheSection
+    procInstCacheSection
+    attachedOpsSection
+    methodsPerGenericTypeSection
+    enumToStringProcsSection
+    methodsPerTypeSection
+    dispatchersSection
+    typeInfoSection  # required by the backend
+    backendFlagsSection
+    aliveSymsSection # beware, this is stored in a `.alivesyms` file.
+    sideChannelSection
+    namespaceSection
+    symnamesSection
+
+  RodFileError* = enum
+    ok, tooBig, cannotOpen, ioFailure, wrongHeader, wrongSection, configMismatch,
+    includeFileChanged
+
+  RodFile* = object
+    f*: File
+    currentSection*: RodSection # for error checking
+    err*: RodFileError # little experiment to see if this works
+                       # better than exceptions.
+
+const
+  RodVersion = 2
+  defaultCookie = [byte(0), byte('R'), byte('O'), byte('D'),
+            byte(sizeof(int)*8), byte(system.cpuEndian), byte(0), byte(RodVersion)]
+
+proc setError(f: var RodFile; err: RodFileError) {.inline.} =
+  f.err = err
+  #raise newException(IOError, "IO error")
+
+proc storePrim*(f: var RodFile; s: string) =
+  ## Stores a string.
+  ## The len is prefixed to allow for later retreival.
+  if f.err != ok: return
+  if s.len >= high(int32):
+    setError f, tooBig
+    return
+  var lenPrefix = int32(s.len)
+  if writeBuffer(f.f, addr lenPrefix, sizeof(lenPrefix)) != sizeof(lenPrefix):
+    setError f, ioFailure
+  else:
+    if s.len != 0:
+      if writeBuffer(f.f, unsafeAddr(s[0]), s.len) != s.len:
+        setError f, ioFailure
+
+proc storePrim*[T](f: var RodFile; x: T) =
+  ## Stores a non-sequence/string `T`.
+  ## If `T` doesn't support `copyMem` and is an object or tuple then the fields
+  ## are written -- the user from context will need to know which `T` to load.
+  if f.err != ok: return
+  when supportsCopyMem(T):
+    if writeBuffer(f.f, unsafeAddr(x), sizeof(x)) != sizeof(x):
+      setError f, ioFailure
+  elif T is tuple:
+    for y in fields(x):
+      storePrim(f, y)
+  elif T is object:
+    for y in fields(x):
+      when y is seq:
+        storeSeq(f, y)
+      else:
+        storePrim(f, y)
+  else:
+    {.error: "unsupported type for 'storePrim'".}
+
+proc storeSeq*[T](f: var RodFile; s: seq[T]) =
+  ## Stores a sequence of `T`s, with the len as a prefix for later retrieval.
+  if f.err != ok: return
+  if s.len >= high(int32):
+    setError f, tooBig
+    return
+  var lenPrefix = int32(s.len)
+  if writeBuffer(f.f, addr lenPrefix, sizeof(lenPrefix)) != sizeof(lenPrefix):
+    setError f, ioFailure
+  else:
+    for i in 0..<s.len:
+      storePrim(f, s[i])
+
+proc storeOrderedTable*[K, T](f: var RodFile; s: OrderedTable[K, T]) =
+  if f.err != ok: return
+  if s.len >= high(int32):
+    setError f, tooBig
+    return
+  var lenPrefix = int32(s.len)
+  if writeBuffer(f.f, addr lenPrefix, sizeof(lenPrefix)) != sizeof(lenPrefix):
+    setError f, ioFailure
+  else:
+    for _, v in s:
+      storePrim(f, v)
+
+proc loadPrim*(f: var RodFile; s: var string) =
+  ## Read a string, the length was stored as a prefix
+  if f.err != ok: return
+  var lenPrefix = int32(0)
+  if readBuffer(f.f, addr lenPrefix, sizeof(lenPrefix)) != sizeof(lenPrefix):
+    setError f, ioFailure
+  else:
+    s = newString(lenPrefix)
+    if lenPrefix > 0:
+      if readBuffer(f.f, unsafeAddr(s[0]), s.len) != s.len:
+        setError f, ioFailure
+
+proc loadPrim*[T](f: var RodFile; x: var T) =
+  ## Load a non-sequence/string `T`.
+  if f.err != ok: return
+  when supportsCopyMem(T):
+    if readBuffer(f.f, unsafeAddr(x), sizeof(x)) != sizeof(x):
+      setError f, ioFailure
+  elif T is tuple:
+    for y in fields(x):
+      loadPrim(f, y)
+  elif T is object:
+    for y in fields(x):
+      when y is seq:
+        loadSeq(f, y)
+      else:
+        loadPrim(f, y)
+  else:
+    {.error: "unsupported type for 'loadPrim'".}
+
+proc loadSeq*[T](f: var RodFile; s: var seq[T]) =
+  ## `T` must be compatible with `copyMem`, see `loadPrim`
+  if f.err != ok: return
+  var lenPrefix = int32(0)
+  if readBuffer(f.f, addr lenPrefix, sizeof(lenPrefix)) != sizeof(lenPrefix):
+    setError f, ioFailure
+  else:
+    s = newSeq[T](lenPrefix)
+    for i in 0..<lenPrefix:
+      loadPrim(f, s[i])
+
+proc loadOrderedTable*[K, T](f: var RodFile; s: var OrderedTable[K, T]) =
+  ## `T` must be compatible with `copyMem`, see `loadPrim`
+  if f.err != ok: return
+  var lenPrefix = int32(0)
+  if readBuffer(f.f, addr lenPrefix, sizeof(lenPrefix)) != sizeof(lenPrefix):
+    setError f, ioFailure
+  else:
+    s = initOrderedTable[K, T](lenPrefix)
+    for i in 0..<lenPrefix:
+      var x = default T
+      loadPrim(f, x)
+      s[x.id] = x
+
+proc storeHeader*(f: var RodFile; cookie = defaultCookie) =
+  ## stores the header which is described by `cookie`.
+  if f.err != ok: return
+  if f.f.writeBytes(cookie, 0, cookie.len) != cookie.len:
+    setError f, ioFailure
+
+proc loadHeader*(f: var RodFile; cookie = defaultCookie) =
+  ## Loads the header which is described by `cookie`.
+  if f.err != ok: return
+  var thisCookie: array[cookie.len, byte] = default(array[cookie.len, byte])
+  if f.f.readBytes(thisCookie, 0, thisCookie.len) != thisCookie.len:
+    setError f, ioFailure
+  elif thisCookie != cookie:
+    setError f, wrongHeader
+
+proc storeSection*(f: var RodFile; s: RodSection) =
+  ## update `currentSection` and writes the bytes value of s.
+  if f.err != ok: return
+  assert f.currentSection < s
+  f.currentSection = s
+  storePrim(f, s)
+
+proc loadSection*(f: var RodFile; expected: RodSection) =
+  ## read the bytes value of s, sets and error if the section is incorrect.
+  if f.err != ok: return
+  var s: RodSection = default(RodSection)
+  loadPrim(f, s)
+  if expected != s and f.err == ok:
+    setError f, wrongSection
+
+proc create*(filename: string): RodFile =
+  ## create the file and open it for writing
+  result = default(RodFile)
+  if not open(result.f, filename, fmWrite):
+    setError result, cannotOpen
+
+proc close*(f: var RodFile) = close(f.f)
+
+proc open*(filename: string): RodFile =
+  ## open the file for reading
+  result = default(RodFile)
+  if not open(result.f, filename, fmRead):
+    setError result, cannotOpen

compiler/icconfig.nim

@@ -1,283 +0,0 @@
-#
-#
-#           The Nim Compiler
-#        (c) Copyright 2026 Andreas Rumpf
-#
-#    See the file "copying.txt", included in this
-#    distribution, for details about the copyright.
-#
-
-## Precompiled config for the incremental compiler (`nim ic`).
-##
-## `nim ic` builds the program by spawning one `nim m` child per module (or
-## strongly-connected import group) plus a final `nim nifc`. Each child is a
-## full Nim process, so each would normally re-read the whole `nim.cfg` chain
-## *and* re-run `config.nims` through the VM — work that is identical for every
-## child and, because of the VM run, far from free. With ~85 modules in the
-## compiler itself that config work is paid ~85 times during `koch bootic`.
-##
-## The fix mirrors Nimony's `.cfg.nif`: the driver parses config once, records
-## the net effect, and the children replay it. Every config-file switch funnels
-## through `processSwitch(..., passPP, ...)` (`nimconf.parseAssignment` and the
-## `switch()` callback in `scriptconfig`), so the recorded sequence of those
-## switches, replayed in order, reproduces an identical `ConfigRef` without any
-## file read or VM run. The one config side effect that does not go through
-## `processSwitch` is `cppDefine` (it mutates `conf.cppDefines` directly), so the
-## resolved set is serialised alongside.
-##
-## Path-search switches are deliberately excluded from the recording (see
-## `commands.processSwitch`): their resolved result already lives in
-## `conf.searchPaths`, which the driver forwards to every child as absolute
-## `--path` arguments; replaying their raw, config-dir-relative arguments here
-## would misresolve.
-
-import options, commands, lineinfos, pathutils, msgs
-import std/[algorithm, os, sets, osproc, times, streams, syncio]
-import "../dist/nimony/src/lib" / [nifbuilder, nifcoreparse]
-
-const
-  IcConfigVersion* = "2"
-    ## Artifact format version. Bump on any layout change here so a child built
-    ## by an older compiler rejects a stale artifact and falls back to normal
-    ## config loading instead of replaying a format it cannot parse.
-
-proc writeIcConfig*(conf: ConfigRef; outfile: string) =
-  ## Serialise the resolved config (the config-file switches recorded during
-  ## `loadConfigs`, the resolved `cppDefines`/`searchPaths`, the nimcache dir, and
-  ## the list of config *source* files for staleness detection) into `outfile`.
-  ## `OnlyIfChanged`: when the content is byte-identical to what is already on
-  ## disk the file is left untouched so its mtime does not advance — otherwise
-  ## every `nim ic` run would re-fire the whole nifmake graph (see `nifler`'s
-  ## `produceConfig`, whose model this mirrors).
-  var b = nifbuilder.open(outfile, writeMode = OnlyIfChanged)
-  b.withTree "stmts":
-    b.withTree "meta":
-      b.addStrLit IcConfigVersion
-    b.withTree "sources":
-      # Every config file read while loading (nim.cfg chain + config.nims), so a
-      # later run can decide via mtimes whether this artifact is still current
-      # (see `sourcesChanged`).
-      for f in conf.configFiles:
-        b.addStrLit f.string
-    b.withTree "nimcache":
-      # Resolved build nimcache. Recorded (unlike the path-search switches) so the
-      # driver, which replays this artifact instead of parsing `nim.cfg`, still
-      # learns a `--nimcache:` set inside `nim.cfg` and builds in the right place.
-      b.addStrLit conf.nimcacheDir.string
-    b.withTree "cppdefines":
-      # HashSet iteration order is unspecified; sort so the artifact is
-      # byte-stable across runs (nifmake keys rebuilds off content changes).
-      var defs: seq[string] = @[]
-      for d in conf.cppDefines: defs.add d
-      sort defs
-      for d in defs: b.addStrLit d
-    b.withTree "searchpaths":
-      # The resolved (absolute) search paths. Path-search *switches* are skipped
-      # below because their raw arguments are config-dir-relative; the net effect
-      # lives here instead, so a replayer with no `--path` command-line arguments
-      # (the `nim ic` driver itself) still resolves imports. `nim m`/`nim nifc`
-      # children also receive these as forwarded `--path` args; the dedup on
-      # replay makes the overlap harmless.
-      for p in conf.searchPaths:
-        b.addStrLit p.string
-    b.withTree "switches":
-      for sw in conf.icConfigSwitches:
-        b.addTree "sw"
-        b.addStrLit sw.switch
-        b.addStrLit sw.arg
-        b.endTree()
-  b.close()
-
-proc applyIcConfig*(conf: ConfigRef; infile: string): bool =
-  ## Replay the precompiled config into `conf`. Returns false (and applies
-  ## nothing meaningful) when the artifact is missing or written by a compiler
-  ## with an incompatible format version, so the caller can fall back to reading
-  ## the config files normally.
-  if not fileExists(infile): return false
-  var pool = newPool()
-  var tags = newTagPool()
-  let
-    stmtsTag = tags.registerTag("stmts")
-    metaTag = tags.registerTag("meta")
-    sourcesTag = tags.registerTag("sources")
-    nimcacheTag = tags.registerTag("nimcache")
-    cppTag = tags.registerTag("cppdefines")
-    pathsTag = tags.registerTag("searchpaths")
-    switchesTag = tags.registerTag("switches")
-    swTag = tags.registerTag("sw")
-  var buf = parseFromFile(infile, 1000, pool, tags)
-  var c = beginRead(buf)
-  if c.kind != TagLit or c.cursorTagId != stmtsTag:
-    endRead(c)
-    return false
-  var version = ""
-  var sawMeta = false
-  let info = unknownLineInfo
-  c.loopInto:
-    if c.kind == TagLit:
-      if c.cursorTagId == metaTag:
-        sawMeta = true
-        c.loopInto:
-          if c.kind == StrLit:
-            version = strVal(c)
-            inc c
-          else:
-            skip c
-      elif c.cursorTagId == nimcacheTag:
-        c.loopInto:
-          if c.kind == StrLit:
-            let nc = strVal(c)
-            # Only when nimcache was not already pinned on the command line: a
-            # `--nimcache:` argument the driver/child was launched with must win
-            # over whatever `nim.cfg` recorded into the artifact.
-            if nc.len > 0 and conf.nimcacheDir.isEmpty:
-              conf.nimcacheDir = AbsoluteDir(nc)
-            inc c
-          else:
-            skip c
-      elif c.cursorTagId == sourcesTag:
-        # Replay does not need the source list; it exists only for
-        # `sourcesChanged`. Skip the whole section.
-        skip c
-      elif c.cursorTagId == cppTag:
-        c.loopInto:
-          if c.kind == StrLit:
-            cppDefine(conf, strVal(c))
-            inc c
-          else:
-            skip c
-      elif c.cursorTagId == pathsTag:
-        c.loopInto:
-          if c.kind == StrLit:
-            # Append preserving the serialised order (which already reflects the
-            # driver's addPath insert-at-front sequence), deduping against any
-            # path a child already received via a forwarded `--path` argument.
-            let d = AbsoluteDir(strVal(c))
-            if not conf.searchPaths.contains(d): conf.searchPaths.add d
-            inc c
-          else:
-            skip c
-      elif c.cursorTagId == switchesTag:
-        c.loopInto:
-          if c.kind == TagLit and c.cursorTagId == swTag:
-            var sw = ""
-            var arg = ""
-            var idx = 0
-            c.loopInto:
-              if c.kind == StrLit:
-                if idx == 0: sw = strVal(c)
-                else: arg = strVal(c)
-                inc idx
-                inc c
-              else:
-                skip c
-            processSwitch(sw, arg, passPP, info, conf)
-          else:
-            skip c
-      else:
-        skip c
-    else:
-      skip c
-  endRead(c)
-  result = sawMeta and version == IcConfigVersion
-
-proc sourcesChanged*(configFile: string): bool =
-  ## True when the precompiled config at `configFile` is missing, malformed,
-  ## written by an incompatible version, or any recorded config *source* file is
-  ## newer than it (or has vanished) — i.e. the artifact must be regenerated.
-  ## Mirrors nifler's `sourcesChanged`: the source list lives inside the artifact
-  ## so this needs no out-of-band knowledge of which `nim.cfg`s were read.
-  if not fileExists(configFile): return true
-  let modtime = getLastModificationTime(configFile)
-  var pool = newPool()
-  var tags = newTagPool()
-  let
-    stmtsTag = tags.registerTag("stmts")
-    metaTag = tags.registerTag("meta")
-    sourcesTag = tags.registerTag("sources")
-  var buf = parseFromFile(configFile, 1000, pool, tags)
-  var c = beginRead(buf)
-  if c.kind != TagLit or c.cursorTagId != stmtsTag:
-    endRead(c)
-    return true
-  var version = ""
-  var depsChanged = false
-  c.loopInto:
-    if c.kind == TagLit and c.cursorTagId == metaTag:
-      c.loopInto:
-        if c.kind == StrLit:
-          version = strVal(c)
-          inc c
-        else:
-          skip c
-    elif c.kind == TagLit and c.cursorTagId == sourcesTag:
-      c.loopInto:
-        if c.kind == StrLit:
-          let dep = strVal(c)
-          if not fileExists(dep) or getLastModificationTime(dep) >= modtime:
-            depsChanged = true
-          inc c
-        else:
-          skip c
-    else:
-      skip c
-  endRead(c)
-  result = depsChanged or version != IcConfigVersion
-
-proc produceIcConfig*(conf: ConfigRef) =
-  ## The `cmdIcConfig` command. By the time it runs, the normal pipeline has
-  ## already fully parsed the `nim.cfg` chain and run `config.nims`, so the
-  ## resolved config is sitting in `conf`; just serialise it to `--o`.
-  let outPath = conf.icConfigOut
-  if outPath.len == 0:
-    rawMessage(conf, errGenerated, "icconfig: missing output path (--icConfigOut)")
-    return
-  createDir(parentDir(outPath))
-  writeIcConfig(conf, outPath)
-
-proc ensureIcConfig*(conf: ConfigRef) =
-  ## Driver-side (`cmdIc`). Make sure an up-to-date precompiled config exists,
-  ## (re)producing it in a *separate* process when missing or stale, then point
-  ## `conf.icPreparsedConfig` at it so the driver replays the very same config its
-  ## `nim m`/`nim nifc` children will — perfect speed (config parsed at most once,
-  ## skipped entirely when nothing changed) and consistency (one producer, every
-  ## process replays its output). The artifact lives in the nimcache derived from
-  ## the command line (pre-config-parse), which is the one the children are told;
-  ## a `--nimcache:` set inside `nim.cfg` is recovered from the artifact itself.
-  let cacheDir = getNimcacheDir(conf).string
-  # Start from a clean cache when the on-disk NIF format stamp is absent or stale
-  # (see `icFormatVersion`). This must happen HERE, before the config artifact is
-  # produced — `commandIc` performs the same check later, but by then the artifact
-  # would already live in the cache and the wipe would delete it.
-  createDir(cacheDir)
-  let versionFile = cacheDir / "ic.version"
-  let stamp = if fileExists(versionFile): readFile(versionFile) else: ""
-  if stamp != icFormatVersion:
-    removeDir(cacheDir)
-    createDir(cacheDir)
-    writeFile(versionFile, icFormatVersion)
-  let outPath = cacheDir / "ic_config.cfg.nif"
-  if not fileExists(outPath) or sourcesChanged(outPath):
-    createDir(cacheDir)
-    # Re-invoke ourselves as the config producer: reuse this process's command
-    # line, dropping the command argument (`ic`) in favour of `icconfig` and the
-    # explicit output path, both BEFORE the project file (anything after the
-    # project is swallowed into `config.arguments` by `cmdLineRest`). The
-    # producer re-reads `nim.cfg` itself.
-    var pargs = @["icconfig", "--icConfigOut:" & outPath]
-    var droppedCmd = false
-    for a in commandLineParams():
-      if not droppedCmd and a.len > 0 and a[0] != '-':
-        droppedCmd = true  # drop the original command token (`ic`)
-      else:
-        pargs.add a
-    let p = startProcess(getAppFilename(), args = pargs,
-                         options = {poStdErrToStdOut})
-    let outp = p.outputStream.readAll()
-    let code = p.waitForExit()
-    p.close()
-    if code != 0 or not fileExists(outPath):
-      rawMessage(conf, errGenerated,
-        "failed to produce precompiled config (exit code " & $code & "):\n" & outp)
-      return
-  conf.icPreparsedConfig = outPath

compiler/importer.nim

@@ -13,7 +13,7 @@ import
   ast, msgs, options, idents, lookups,
   semdata, modulepaths, sigmatch, lineinfos,
   modulegraphs, wordrecg
-from std/strutils import `%`, startsWith, replace
+from std/strutils import `%`, startsWith
 from std/sequtils import addUnique
 import std/[sets, tables, intsets]
 
@@ -108,8 +108,8 @@ proc rawImportSymbol(c: PContext, s, origin: PSym; importSet: var IntSet) =
           else:
             importPureEnumField(c, e)
   else:
-    if s.kind == skConverter: addConverter(c, s)
-    if hasPattern(s): addPattern(c, s)
+    if s.kind == skConverter: addConverter(c, LazySym(sym: s))
+    if hasPattern(s): addPattern(c, LazySym(sym: s))
   if s.owner != origin:
     c.exportIndirections.incl((origin.id, s.id))
 
@@ -190,19 +190,22 @@ proc addImport(c: PContext; im: sink ImportedModule) =
 template addUnnamedIt(c: PContext, fromMod: PSym; filter: untyped) {.dirty.} =
   for it in mitems c.graph.ifaces[fromMod.position].converters:
     if filter:
-      if sfExported in it.flags:
+      loadPackedSym(c.graph, it)
+      if sfExported in it.sym.flags:
         addConverter(c, it)
   for it in mitems c.graph.ifaces[fromMod.position].patterns:
     if filter:
-      if sfExported in it.flags:
+      loadPackedSym(c.graph, it)
+      if sfExported in it.sym.flags:
         addPattern(c, it)
   for it in mitems c.graph.ifaces[fromMod.position].pureEnums:
     if filter:
-      importPureEnumFields(c, it, it.typ)
+      loadPackedSym(c.graph, it)
+      importPureEnumFields(c, it.sym, it.sym.typ)
 
 proc importAllSymbolsExcept(c: PContext, fromMod: PSym, exceptSet: IntSet) =
   c.addImport ImportedModule(m: fromMod, mode: importExcept, exceptSet: exceptSet)
-  addUnnamedIt(c, fromMod, it.name.id notin exceptSet)
+  addUnnamedIt(c, fromMod, it.sym.name.id notin exceptSet)
 
 proc importAllSymbols*(c: PContext, fromMod: PSym) =
   c.addImport ImportedModule(m: fromMod, mode: importAll)
@@ -289,8 +292,9 @@ proc myImportModule(c: PContext, n: var PNode, importStmtResult: PNode): PSym =
       c.recursiveDep = err
 
     let trackUnusedImport = warnUnusedImportX in c.config.notes
+    var realModule: PSym
     discard pushOptionEntry(c)
-    let realModule = c.graph.importModuleCallback(c.graph, c.module, f)
+    realModule = c.graph.importModuleCallback(c.graph, c.module, f)
     result = importModuleAs(c, n, realModule, transf.importHidden, trackUnusedImport)
     popOptionEntry(c)
 
@@ -304,9 +308,9 @@ proc myImportModule(c: PContext, n: var PNode, importStmtResult: PNode): PSym =
       var prefix = ""
       if realModule.constraint != nil: prefix = realModule.constraint.strVal & "; "
       message(c.config, n.info, warnDeprecated, prefix & realModule.name.s & " is deprecated")
-    let moduleNameNorm = getModuleName(c.config, n).replace("\\", "/")
-    if belongsToStdlib(c.graph, result) and not startsWith(moduleNameNorm, stdPrefix) and
-        not startsWith(moduleNameNorm, "system/") and not startsWith(moduleNameNorm, "packages/"):
+    let moduleName = getModuleName(c.config, n)
+    if belongsToStdlib(c.graph, result) and not startsWith(moduleName, stdPrefix) and
+        not startsWith(moduleName, "system/") and not startsWith(moduleName, "packages/"):
       message(c.config, n.info, warnStdPrefix, realModule.name.s)
 
     proc suggestMod(n: PNode; s: PSym) =

compiler/injectdestructors.nim

@@ -69,14 +69,12 @@ proc hasDestructor(c: Con; t: PType): bool {.inline.} =
   result = ast.hasDestructor(t)
   when toDebug.len > 0:
     # for more effective debugging
-    if not result and c.graph.config.selectedGC in {gcArc, gcOrc, gcYrc, gcAtomicArc}:
+    if not result and c.graph.config.selectedGC in {gcArc, gcOrc, gcAtomicArc}:
       assert(not containsGarbageCollectedRef(t))
 
-proc getTemp(c: var Con; s: var Scope; typ: PType; info: TLineInfo; needsInit: bool): PNode =
+proc getTemp(c: var Con; s: var Scope; typ: PType; info: TLineInfo): PNode =
   let sym = newSym(skTemp, getIdent(c.graph.cache, ":tmpD"), c.idgen, c.owner, info)
   sym.typ = typ
-  if not needsInit:
-    sym.incl sfNoInit
   s.vars.add(sym)
   result = newSymNode(sym)
 
@@ -167,7 +165,7 @@ proc isLastReadImpl(n: PNode; c: var Con; scope: var Scope): bool =
 
 template hasDestructorOrAsgn(c: var Con, typ: PType): bool =
   # bug #23354; an object type could have a non-trivial assignements when it is passed to a sink parameter
-  hasDestructor(c, typ) or (c.graph.config.selectedGC in {gcArc, gcOrc, gcYrc, gcAtomicArc} and
+  hasDestructor(c, typ) or (c.graph.config.selectedGC in {gcArc, gcOrc, gcAtomicArc} and
         typ.kind == tyObject and not isTrivial(getAttachedOp(c.graph, typ, attachedAsgn)))
 
 proc isLastRead(n: PNode; c: var Con; s: var Scope): bool =
@@ -304,7 +302,7 @@ proc genSink(c: var Con; s: var Scope; dest, ri: PNode; flags: set[MoveOrCopyFla
       if deepAliases(dest, ri):
         # consider: x = x + y, it is wrong to destroy the destination first!
         # tmp to support self assignments
-        let tmp = c.getTemp(s, dest.typ, dest.info, needsInit = false)
+        let tmp = c.getTemp(s, dest.typ, dest.info)
         result = newTree(nkStmtList, newTree(nkFastAsgn, tmp, dest), newTree(nkFastAsgn, dest, ri),
                          c.genDestroy(tmp))
       else:
@@ -331,14 +329,14 @@ proc isCriticalLink(dest: PNode): bool {.inline.} =
   result = dest.kind != nkSym
 
 proc finishCopy(c: var Con; result, dest: PNode; flags: set[MoveOrCopyFlag]; isFromSink: bool) =
-  if c.graph.config.selectedGC in {gcOrc, gcYrc} and IsExplicitSink notin flags:
+  if c.graph.config.selectedGC == gcOrc and IsExplicitSink notin flags:
     # add cyclic flag, but not to sink calls, which IsExplicitSink generates
     let t = dest.typ.skipTypes(tyUserTypeClasses + {tyGenericInst, tyAlias, tySink, tyDistinct})
     if cyclicType(c.graph, t):
       result.add boolLit(c.graph, result.info, isFromSink or isCriticalLink(dest))
 
 proc genMarkCyclic(c: var Con; result, dest: PNode) =
-  if c.graph.config.selectedGC in {gcOrc, gcYrc}:
+  if c.graph.config.selectedGC == gcOrc:
     let t = dest.typ.skipTypes({tyGenericInst, tyAlias, tySink, tyDistinct})
     if cyclicType(c.graph, t):
       if t.kind == tyRef:
@@ -373,7 +371,7 @@ proc genDiscriminantAsgn(c: var Con; s: var Scope; n: PNode): PNode =
   # but fields within active case branch might need destruction
 
   # tmp to support self assignments
-  let tmp = c.getTemp(s, n[1].typ, n.info, needsInit = false)
+  let tmp = c.getTemp(s, n[1].typ, n.info)
 
   result = newTree(nkStmtList)
   result.add newTree(nkFastAsgn, tmp, p(n[1], c, s, consumed))
@@ -459,50 +457,49 @@ proc isCapturedVar(n: PNode): bool =
   else: result = false
 
 proc passCopyToSink(n: PNode; c: var Con; s: var Scope): PNode =
+  result = newNodeIT(nkStmtListExpr, n.info, n.typ)
   let nTyp = n.typ.skipTypes(tyUserTypeClasses)
-  if not hasDestructorOrAsgn(c, nTyp):
-    # Non-managed (plain-old-data) type: no ownership transfer is needed.
-    # Return the expression directly — no temp required.
-    if c.graph.config.selectedGC in {gcArc, gcOrc, gcYrc, gcAtomicArc}:
+  let tmp = c.getTemp(s, nTyp, n.info)
+  if hasDestructorOrAsgn(c, nTyp):
+    let typ = nTyp.skipTypes({tyGenericInst, tyAlias, tySink})
+    let op = getAttachedOp(c.graph, typ, attachedDup)
+    if op != nil and tfHasOwned notin typ.flags:
+      if sfError in op.flags:
+        c.checkForErrorPragma(nTyp, n, "=dup")
+      else:
+        let copyOp = getAttachedOp(c.graph, typ, attachedAsgn)
+        if copyOp != nil and sfError in copyOp.flags and
+           sfOverridden notin op.flags:
+          c.checkForErrorPragma(nTyp, n, "=dup", inferredFromCopy = true)
+
+      let src = p(n, c, s, normal)
+      var newCall = newTreeIT(nkCall, src.info, src.typ,
+            newSymNode(op),
+            src)
+      c.finishCopy(newCall, n, {}, isFromSink = true)
+      result.add newTreeI(nkFastAsgn,
+          src.info, tmp,
+          newCall
+      )
+    else:
+      result.add c.genWasMoved(tmp)
+      var m = c.genCopy(tmp, n, {})
+      m.add p(n, c, s, normal)
+      c.finishCopy(m, n, {}, isFromSink = true)
+      result.add m
+    if isLValue(n) and not isCapturedVar(n) and nTyp.skipTypes(abstractInst).kind != tyRef and c.inSpawn == 0:
+      message(c.graph.config, n.info, hintPerformance,
+        ("passing '$1' to a sink parameter introduces an implicit copy; " &
+        "if possible, rearrange your program's control flow to prevent it") % $n)
+    if c.inEnsureMove > 0:
+      localError(c.graph.config, n.info, errFailedMove,
+        ("cannot move '$1', passing '$1' to a sink parameter introduces an implicit copy") % $n)
+  else:
+    if c.graph.config.selectedGC in {gcArc, gcOrc, gcAtomicArc}:
       assert(not containsManagedMemory(nTyp))
     if nTyp.skipTypes(abstractInst).kind in {tyOpenArray, tyVarargs}:
       localError(c.graph.config, n.info, "cannot create an implicit openArray copy to be passed to a sink parameter")
-    return p(n, c, s, normal)
-  result = newNodeIT(nkStmtListExpr, n.info, n.typ)
-  let tmp = c.getTemp(s, nTyp, n.info, needsInit = false)
-  let typ = nTyp.skipTypes({tyGenericInst, tyAlias, tySink})
-  let op = getAttachedOp(c.graph, typ, attachedDup)
-  if op != nil and tfHasOwned notin typ.flags:
-    if sfError in op.flags:
-      c.checkForErrorPragma(nTyp, n, "=dup")
-    else:
-      let copyOp = getAttachedOp(c.graph, typ, attachedAsgn)
-      if copyOp != nil and sfError in copyOp.flags and
-         sfOverridden notin op.flags:
-        c.checkForErrorPragma(nTyp, n, "=dup", inferredFromCopy = true)
-
-    let src = p(n, c, s, normal)
-    var newCall = newTreeIT(nkCall, src.info, src.typ,
-          newSymNode(op),
-          src)
-    c.finishCopy(newCall, n, {}, isFromSink = true)
-    result.add newTreeI(nkFastAsgn,
-        src.info, tmp,
-        newCall
-    )
-  else:
-    result.add c.genWasMoved(tmp)
-    var m = c.genCopy(tmp, n, {})
-    m.add p(n, c, s, normal)
-    c.finishCopy(m, n, {}, isFromSink = true)
-    result.add m
-  if isLValue(n) and not isCapturedVar(n) and nTyp.skipTypes(abstractInst).kind != tyRef and c.inSpawn == 0:
-    message(c.graph.config, n.info, hintPerformance,
-      ("passing '$1' to a sink parameter introduces an implicit copy; " &
-      "if possible, rearrange your program's control flow to prevent it") % $n)
-  if c.inEnsureMove > 0:
-    localError(c.graph.config, n.info, errFailedMove,
-      ("cannot move '$1', passing '$1' to a sink parameter introduces an implicit copy") % $n)
+    result.add newTree(nkAsgn, tmp, p(n, c, s, normal))
   # Since we know somebody will take over the produced copy, there is
   # no need to destroy it.
   result.add tmp
@@ -533,7 +530,7 @@ proc ensureDestruction(arg, orig: PNode; c: var Con; s: var Scope): PNode =
     # produce temp creation for (fn, env). But we need to move 'env'?
     # This was already done in the sink parameter handling logic.
     result = newNodeIT(nkStmtListExpr, arg.info, arg.typ)
-    let tmp = c.getTemp(s, arg.typ, arg.info, true)
+    let tmp = c.getTemp(s, arg.typ, arg.info)
     result.add c.genSink(s, tmp, arg, {IsDecl})
     result.add tmp
     s.final.add c.genDestroy(tmp)
@@ -612,7 +609,7 @@ template processScopeExpr(c: var Con; s: var Scope; ret: PNode, processCall: unt
   # There is a possibility to do this check: s.wasMoved.len > 0 or s.final.len > 0
   # later and use it to eliminate the temporary when theres no need for it, but its
   # tricky because you would have to intercept moveOrCopy at a certain point
-  let tmp = c.getTemp(s.parent[], ret.typ, ret.info, needsInit = true)
+  let tmp = c.getTemp(s.parent[], ret.typ, ret.info)
   tmp.sym.flags = tmpFlags
   let cpy = if hasDestructor(c, ret.typ) and
                 ret.typ.kind notin {tyOpenArray, tyVarargs}:
@@ -773,7 +770,7 @@ proc pRaiseStmt(n: PNode, c: var Con; s: var Scope): PNode =
       result = copyNode(n)
       result.add call
     else:
-      let tmp = c.getTemp(s, n[0].typ, n.info, needsInit = true)
+      let tmp = c.getTemp(s, n[0].typ, n.info)
       var m = c.genCopyNoCheck(tmp, n[0], attachedAsgn)
       m.add p(n[0], c, s, normal)
       c.finishCopy(m, n[0], {}, isFromSink = false)
@@ -803,23 +800,6 @@ proc hasCustomDestructor(c: Con, t: PType): bool =
     obj = skipTypes(obj.baseClass, abstractPtrs)
     result = result or isCustomDestructor(c, obj)
 
-const
-  exprBranchKinds = {nkStmtListExpr, nkBlockExpr, nkIfExpr, nkCaseStmt,
-                     nkTryStmt, nkPragmaBlock}
-
-proc distributeAsgn(asgnKind: TNodeKind; dest, ri: PNode; c: var Con; s: var Scope): PNode =
-  ## Distributes an assignment ``dest = ri`` into the leaf expressions of
-  ## ``ri`` when ``ri`` is an expression-based control flow construct. This
-  ## avoids creating pointless intermediate temporaries (bug #25850). The
-  ## descent is recursive so that nestings like ``block: ...; if c: a else: b``
-  ## assign directly to ``dest`` instead of going through a temp per branch.
-  if ri.kind in exprBranchKinds:
-    template process(child, s): untyped =
-      distributeAsgn(asgnKind, dest, child, c, s)
-    handleNestedTempl(ri, process, willProduceStmt = true)
-  else:
-    result = newTree(asgnKind, dest, p(ri, c, s, consumed))
-
 proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSingleUsedTemp}; inReturn = false): PNode =
   if n.kind in {nkStmtList, nkStmtListExpr, nkBlockStmt, nkBlockExpr, nkIfStmt,
                 nkIfExpr, nkCaseStmt, nkWhen, nkWhileStmt, nkParForStmt, nkTryStmt, nkPragmaBlock}:
@@ -946,7 +926,7 @@ proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSing
 
       if n[0].kind == nkSym and n[0].sym.magic in {mNew, mNewFinalize}:
         result[0] = copyTree(n[0])
-        if c.graph.config.selectedGC in {gcHooks, gcArc, gcAtomicArc, gcOrc, gcYrc}:
+        if c.graph.config.selectedGC in {gcHooks, gcArc, gcAtomicArc, gcOrc}:
           let destroyOld = c.genDestroy(result[1])
           result = newTree(nkStmtList, destroyOld, result)
       else:
@@ -1021,11 +1001,6 @@ proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSing
         result = moveOrCopy(p(n[0], c, s, mode), n[1], c, s, flags)
       elif isDiscriminantField(n[0]):
         result = c.genDiscriminantAsgn(s, n)
-      elif n[1].kind in exprBranchKinds:
-        # Distribute the assignment into each branch to avoid
-        # creating pointless temporaries for expression-based control flow.
-        let dest = p(n[0], c, s, mode)
-        result = distributeAsgn(n.kind, dest, n[1], c, s)
       else:
         result = copyNode(n)
         result.add p(n[0], c, s, mode)
@@ -1179,7 +1154,7 @@ proc ownsData(c: var Con; s: var Scope; orig: PNode; flags: set[MoveOrCopyFlag])
       break
   if n.kind in nkCallKinds and n.typ != nil and hasDestructor(c, n.typ):
     result = newNodeIT(nkStmtListExpr, orig.info, orig.typ)
-    let tmp = c.getTemp(s, n.typ, n.info, needsInit = true)
+    let tmp = c.getTemp(s, n.typ, n.info)
     tmp.sym.flagsImpl.incl sfSingleUsedTemp
     result.add newTree(nkFastAsgn, tmp, copyTree(n))
     s.final.add c.genDestroy(tmp)

compiler/int128.nim

@@ -460,9 +460,7 @@ proc addInt128*(result: var string; value: Int128) =
     var i = initialSize
     var j = high(result)
     while i < j:
-      let tmp = result[i]
-      result[i] = result[j]
-      result[j] = tmp
+      swap(result[i], result[j])
       i += 1
       j -= 1
 

compiler/itemids.nim

@@ -1,98 +0,0 @@
-#
-#
-#           The Nim Compiler
-#        (c) Copyright 2026 Andreas Rumpf
-#
-#    See the file "copying.txt", included in this
-#    distribution, for details about the copyright.
-#
-
-## `ItemId` is the identity of a symbol or type: a `(module, item)` pair.
-##
-## The fields are private on purpose: the module half reserves bit 30 as the
-## "backend minted" marker, so all construction and inspection has to go
-## through this module's API and the marker bit can never leak into module
-## indexing or arithmetic.
-##
-## Three id spaces coexist per module:
-## - Semantic-phase and NIF-loader ids: `itemId(module, item)` with `item > 0`.
-## - Backend-minted ids (IC codegen, `nim nifc`: transf labels and temps,
-##   lifted hooks): `backendItemId` sets `BackendModuleBit`, so these can
-##   never compare equal to a loader id even though both counters mint the
-##   same small `item` range in one process. They never cross a process
-##   boundary and must never be written to a NIF file.
-## - Derived env/tuple-field ids (`lowerings.addField`): the source local's
-##   id with `item` negated. `derivedFieldId` preserves the backend marker,
-##   keeping the derivation collision-free for both id spaces above.
-
-import std/hashes
-
-when defined(nimPreviewSlimSystem):
-  import std/assertions
-
-const
-  BackendModuleBit = 0x4000_0000'i32
-    # Bit 30 of the module field. Bit 31 stays clear so marked module values
-    # remain non-negative and cannot be mistaken for the special negative
-    # module ids like `PackageModuleId`.
-  PackageModuleId* = -3'i32
-
-type
-  ItemId* = object
-    moduleBits: int32
-    itemBits: int32
-
-proc itemId*(module, item: int32): ItemId {.inline.} =
-  assert module < 0 or (module and BackendModuleBit) == 0
-  ItemId(moduleBits: module, itemBits: item)
-
-proc backendItemId*(module, item: int32): ItemId {.inline.} =
-  ## An id minted during IC codegen; distinct from every `itemId` of the
-  ## same module so that the loader's stub counter and the backend's counter
-  ## cannot collide in id-keyed tables.
-  assert module >= 0 and (module and BackendModuleBit) == 0
-  ItemId(moduleBits: module or BackendModuleBit, itemBits: item)
-
-proc module*(x: ItemId): int32 {.inline.} =
-  if x.moduleBits >= 0: x.moduleBits and not BackendModuleBit
-  else: x.moduleBits
-
-proc item*(x: ItemId): int32 {.inline.} = x.itemBits
-
-proc isBackendMinted*(x: ItemId): bool {.inline.} =
-  x.moduleBits >= 0 and (x.moduleBits and BackendModuleBit) != 0
-
-proc derivedFieldId*(source: ItemId): ItemId {.inline.} =
-  ## The id of the env/tuple field that `lowerings.addField` derives for a
-  ## captured local: `item` negated, module bits (including the backend
-  ## marker) preserved.
-  ItemId(moduleBits: source.moduleBits, itemBits: -abs(source.itemBits))
-
-proc matchesDerivedFieldId*(field, source: ItemId): bool {.inline.} =
-  ## Does `field` carry the id `derivedFieldId` would derive for `source`?
-  ## `source` may itself already be the derived field id.
-  field.moduleBits == source.moduleBits and
-    field.itemBits == -abs(source.itemBits)
-
-proc `==`*(a, b: ItemId): bool {.inline.} =
-  # raw bit comparison: a backend-minted id never equals a loader id
-  a.itemBits == b.itemBits and a.moduleBits == b.moduleBits
-
-proc hash*(x: ItemId): Hash =
-  var h: Hash = hash(x.moduleBits)
-  h = h !& hash(x.itemBits)
-  result = !$h
-
-proc `$`*(x: ItemId): string =
-  result = "(module: " & $x.module & ", item: " & $x.itemBits
-  if x.isBackendMinted: result.add ", backend"
-  result.add ")"
-
-const
-  moduleShift = when defined(cpu32): 20 else: 24
-
-proc toId*(a: ItemId): int {.inline.} =
-  ## Packs an ItemId into a single int. Uses the raw module bits so the
-  ## backend marker keeps the two id spaces disjoint (bit 30 shifts to
-  ## bit 54; like the module/item split itself this needs a 64-bit int).
-  (a.moduleBits.int shl moduleShift) + a.itemBits.int

compiler/jsgen.nim

@@ -1544,7 +1544,7 @@ proc genSymAddr(p: PProc, n: PNode, typ: PType, r: var TCompRes) =
     r.res = s.loc.snippet
     r.address = ""
     r.typ = etyNone
-  of skVar, skLet, skResult, skTemp, skForVar:
+  of skVar, skLet, skResult:
     r.kind = resExpr
     let jsType = mapType(p):
       if typ.isNil:
@@ -2018,12 +2018,8 @@ proc createVar(p: PProc, typ: PType, indirect: bool): Rope =
     if indirect: result = "[$1]" % [result]
   of tyTuple:
     result = rope("{")
-    var first = true
     for i in 0..<t.len:
-      # Do not produce code for void types
-      if isEmptyType(t[i]): continue
-      if not first: result.add(", ")
-      first = false
+      if i > 0: result.add(", ")
       result.addf("Field$1: $2", [i.rope,
             createVar(p, t[i], false)])
     result.add("}")

compiler/lambdalifting.nim

@@ -164,21 +164,9 @@ proc getClosureIterResult*(g: ModuleGraph; iter: PSym; idgen: IdGenerator): PSym
     incl(result.flagsImpl, sfUsed)
     iter.ast.add newSymNode(result)
 
-proc closureParams(routine: PSym): PNode =
-  ## The formal parameters node lambda lifting reads and extends. In a
-  ## from-source compilation `routine.ast[paramsPos]` and `routine.typ.n` are the
-  ## very same node (see the `typ.n.len` based position math below). Under IC the
-  ## loaded proc AST omits the parameters (they are kept only in `typ.n`), so
-  ## restore the shared node here.
-  result = routine.ast[paramsPos]
-  if (result == nil or result.kind == nkEmpty) and routine.typ != nil and
-      routine.typ.n != nil and routine.ast.len > paramsPos:
-    result = routine.typ.n
-    routine.ast[paramsPos] = result
-
 proc addHiddenParam(routine: PSym, param: PSym) =
   assert param.kind == skParam
-  var params = closureParams(routine)
+  var params = routine.ast[paramsPos]
   # -1 is correct here as param.position is 0 based but we have at position 0
   # some nkEffect node:
   param.position = routine.typ.n.len-1
@@ -189,8 +177,7 @@ proc addHiddenParam(routine: PSym, param: PSym) =
 
 proc getEnvParam*(routine: PSym): PSym =
   if routine.ast.isNil: return nil
-  let params = closureParams(routine)
-  if params == nil or params.len == 0: return nil
+  let params = routine.ast[paramsPos]
   let hidden = lastSon(params)
   if hidden.kind == nkSym and hidden.sym.kind == skParam and hidden.sym.name.s == paramName:
     result = hidden.sym
@@ -229,10 +216,6 @@ proc newAsgnStmt(le, ri: PNode, info: TLineInfo): PNode =
   result[0] = le
   result[1] = ri
 
-proc markInjectDestructors(s: PSym) {.inline.} =
-  backendEnsureMutable s
-  s.flagsImpl.incl sfInjectDestructors
-
 proc makeClosure*(g: ModuleGraph; idgen: IdGenerator; prc: PSym; env: PNode; info: TLineInfo): PNode =
   result = newNodeIT(nkClosure, info, prc.typ)
   result.add(newSymNode(prc))
@@ -245,7 +228,7 @@ proc makeClosure*(g: ModuleGraph; idgen: IdGenerator; prc: PSym; env: PNode; inf
   #if isClosureIterator(result.typ):
   createTypeBoundOps(g, nil, result.typ, info, idgen)
   if tfHasAsgn in result.typ.flags or optSeqDestructors in g.config.globalOptions:
-    markInjectDestructors(prc)
+    prc.incl sfInjectDestructors
 
 template liftingHarmful(conf: ConfigRef; owner: PSym): bool =
   ## lambda lifting can be harmful for JS-like code generators.
@@ -257,7 +240,7 @@ proc createTypeBoundOpsLL(g: ModuleGraph; refType: PType; info: TLineInfo; idgen
     createTypeBoundOps(g, nil, refType.elementType, info, idgen)
     createTypeBoundOps(g, nil, refType, info, idgen)
     if tfHasAsgn in refType.flags or optSeqDestructors in g.config.globalOptions:
-      markInjectDestructors(owner)
+      owner.incl sfInjectDestructors
 
 proc genCreateEnv(env: PNode): PNode =
   var c = newNodeIT(nkObjConstr, env.info, env.typ)
@@ -307,7 +290,6 @@ proc markAsClosure(g: ModuleGraph; owner: PSym; n: PNode) =
   elif not (owner.typ.isClosure or owner.isNimcall and not owner.isExplicitCallConv or isEnv):
     localError(g.config, n.info, "illegal capture '$1' because '$2' has the calling convention: <$3>" %
       [s.name.s, owner.name.s, $owner.typ.callConv])
-  unsealForTransform(owner.typ)
   incl(owner.typ, tfCapturesEnv)
   if not isEnv:
     owner.typ.callConv = ccClosure
@@ -426,12 +408,6 @@ Consider:
 proc isTypeOf(n: PNode): bool =
   n.kind == nkSym and n.sym.magic in {mTypeOf, mType}
 
-proc isEnvTypeForRoutine(envTyp: PType; routine: PSym): bool =
-  ## True if `envTyp` is (maybe wrapped) env object type owned by `routine`, as
-  ## created by `getEnvTypeForOwner` / `createEnvObj`.
-  let obj = envTyp.skipTypes({tyOwned, tyRef, tyPtr})
-  result = obj.kind == tyObject and obj.owner.id == routine.id
-
 proc addClosureParam(c: var DetectionPass; fn: PSym; info: TLineInfo) =
   var cp = getEnvParam(fn)
   let owner = if fn.kind == skIterator: fn else: fn.skipGenericOwner
@@ -442,13 +418,7 @@ proc addClosureParam(c: var DetectionPass; fn: PSym; info: TLineInfo) =
     cp.typ = t
     addHiddenParam(fn, cp)
   elif cp.typ != t and fn.kind != skIterator:
-    # Nested `liftLambdas` uses a fresh `DetectionPass`, so `getEnvTypeForOwner`
-    # can allocate another PType for the same logical env; the hidden param from
-    # the inner pass is authoritative (bug #21242).
-    if isEnvTypeForRoutine(cp.typ, owner) and isEnvTypeForRoutine(t, owner):
-      c.ownerToType[owner.id] = cp.typ
-    else:
-      localError(c.graph.config, fn.info, "internal error: inconsistent environment type")
+    localError(c.graph.config, fn.info, "internal error: inconsistent environment type")
   #echo "adding closure to ", fn.name.s
 
 proc iterEnvHasUpField(g: ModuleGraph, iter: PSym): bool =
@@ -654,7 +624,7 @@ proc rawClosureCreation(owner: PSym;
         if owner.kind != skMacro:
           createTypeBoundOps(d.graph, nil, fieldAccess.typ, env.info, d.idgen)
         if tfHasAsgn in fieldAccess.typ.flags or optSeqDestructors in d.graph.config.globalOptions:
-          markInjectDestructors(owner)
+          owner.incl sfInjectDestructors
 
   let upField = lookupInRecord(env.typ.skipTypes({tyOwned, tyRef, tyPtr}).n, getIdent(d.graph.cache, upName))
   if upField != nil:

compiler/layeredtable.nim

@@ -46,11 +46,12 @@ proc setToPreviousLayer*(pt: var LayeredIdTable) {.inline.} =
   when useRef:
     pt = pt.nextLayer
   else:
-    # Must read nextLayer into a temp before destroying pt:
-    # `pt = pt.nextLayer[]` would call eqcopy(&pt, &(*pt.nextLayer)) which
-    # decrements pt.nextLayer's rc (freeing it) before reading pt.nextLayer.nextLayer.
-    let tmp = pt.nextLayer[]
-    pt = tmp
+    when defined(gcDestructors):
+      pt = pt.nextLayer[]
+    else:
+      # workaround refc
+      let tmp = pt.nextLayer[]
+      pt = tmp
 
 iterator pairs*(pt: LayeredIdTable): (ItemId, PType) =
   var tm = pt

compiler/lexer.nim

@@ -316,28 +316,6 @@ proc getNumber(L: var Lexer, result: var Token) =
     L.bufpos = msgPos
     lexMessage(L, msgKind, msg % t.literal)
 
-  proc checkBitWidth(L: var Lexer, base: NumericalBase, tokType: TokType, 
-                     numDigits: int, startpos: int) =
-    # Check bit width for non-base-10 literals
-    # Warn if the digit count exceeds what can fit in the target type
-    let bitsPerDigit = case base
-      of base2: 1
-      of base8: 3
-      of base16: 4
-      else: raiseAssert "unreachable"
-    let bitWidth = case tokType
-      of tkInt8Lit, tkUInt8Lit: 8
-      of tkInt16Lit, tkUInt16Lit: 16
-      of tkInt32Lit, tkUInt32Lit: 32
-      of tkInt64Lit, tkUIntLit, tkIntLit, tkUInt64Lit: 64
-      else: raiseAssert "unreachable"
-    # Maximum digits = ceil(bitWidth / bitsPerDigit) = (bitWidth + bitsPerDigit - 1) div bitsPerDigit
-    let maxDigits = (bitWidth + bitsPerDigit - 1) div bitsPerDigit
-    if numDigits > maxDigits:
-      lexMessageLitNum(L,
-        "number has " & $numDigits & " digits but type only supports " &
-        $maxDigits & " digits: '$1'", startpos, warnLongLiterals)
-
   var
     xi: BiggestInt
     isBase10 = true
@@ -513,11 +491,6 @@ proc getNumber(L: var Lexer, result: var Token) =
           setNumber result.fNumber, (cast[ptr float64](addr(xi)))[]
         else: internalError(L.config, getLineInfo(L), "getNumber")
 
-        # Check bit width for non-base-10 literals
-        # Warn if the digit count exceeds what can fit in the target type
-        if result.base != base10 and result.tokType in {tkIntLit..tkUInt64Lit} and numDigits > 0:
-          checkBitWidth(L, result.base, result.tokType, numDigits, startpos)
-
         # Bounds checks. Non decimal literals are allowed to overflow the range of
         # the datatype as long as their pattern don't overflow _bitwise_, hence
         # below checks of signed sizes against uint*.high is deliberate:
@@ -923,7 +896,7 @@ proc getSymbol(L: var Lexer, tok: var Token) =
     tok.tokType = tkSymbol
   else:
     tok.tokType = TokType(tok.ident.id + ord(tkSymbol))
-    if suspicious and {optStyleHint, optStyleError, optStyleWarning} * L.config.globalOptions != {}:
+    if suspicious and {optStyleHint, optStyleError} * L.config.globalOptions != {}:
       lintReport(L.config, getLineInfo(L), tok.ident.s.normalize, tok.ident.s)
   L.bufpos = pos
 
@@ -1349,7 +1322,7 @@ proc rawGetTok*(L: var Lexer, tok: var Token) =
           lexMessage(L, errGenerated, "invalid token: no whitespace between number and identifier")
     of '-':
       if L.buf[L.bufpos+1] in {'0'..'9'} and
-          (L.bufpos == 0 or L.buf[L.bufpos-1] in UnaryMinusWhitelist):
+          (L.bufpos-1 == 0 or L.buf[L.bufpos-1] in UnaryMinusWhitelist):
         # x)-23 # binary minus
         # ,-23  # unary minus
         # \n-78 # unary minus? Yes.

compiler/liftdestructors.nim

@@ -163,7 +163,7 @@ proc fillBodyObj(c: var TLiftCtx; n, body, x, y: PNode; enforceDefaultOp: bool,
     if c.filterDiscriminator != nil: return
     let f = n.sym
     let b = if c.kind == attachedTrace: y else: y.dotField(f)
-    if (sfCursor in f.flags and c.g.config.selectedGC in {gcArc, gcAtomicArc, gcOrc, gcYrc, gcHooks}) or
+    if (sfCursor in f.flags and c.g.config.selectedGC in {gcArc, gcAtomicArc, gcOrc, gcHooks}) or
         enforceDefaultOp:
       defaultOp(c, f.typ, body, x.dotField(f), b)
     else:
@@ -558,22 +558,6 @@ proc declareTempOf(c: var TLiftCtx; body: PNode; value: PNode): PNode =
   v.addVar(result, value)
   body.add v
 
-proc considerInferDupFromCopy(c: var TLiftCtx; t: PType; body, x, y: PNode): bool =
-  ## For `=dup`, if no explicit hook exists, try to infer from `=copy` hook
-  ## to maintain backward compatibility. Returns true if inference was applied.
-  if c.kind == attachedDup:
-    var op2 = getAttachedOp(c.g, t, attachedAsgn)
-    if op2 != nil and sfOverridden in op2.flags:
-      #markUsed(c.g.config, c.info, op, c.g.usageSym)
-      onUse(c.info, op2)
-      body.add genBuiltin(c, mWasMoved, "wasMoved", x)
-      body.add newHookCall(c, op2, x, y)
-      result = true
-    else:
-      result = false
-  else:
-    result = false
-
 proc addIncStmt(c: var TLiftCtx; body, i: PNode) =
   let incCall = genBuiltin(c, mInc, "inc", i)
   incCall.add lowerings.newIntLit(c.g, c.info, 1)
@@ -592,12 +576,10 @@ proc setLenStrCall(c: var TLiftCtx; x, y: PNode): PNode =
   result = genBuiltin(c, mSetLengthStr, "setLen", x) # genAddr(g, x))
   result.add lenCall
 
-proc setLenSeqCall(c: var TLiftCtx; t: PType; x, y: PNode; noinit = false): PNode =
+proc setLenSeqCall(c: var TLiftCtx; t: PType; x, y: PNode): PNode =
   let lenCall = genBuiltin(c, mLengthSeq, "len", y)
   lenCall.typ = getSysType(c.g, x.info, tyInt)
-  let name = if noinit: "setLenUninit" else: "setLen"
-  let magic = if noinit: mSetLengthSeqUninit else: mSetLengthSeq
-  var op = getSysMagic(c.g, x.info, name, magic)
+  var op = getSysMagic(c.g, x.info, "setLen", mSetLengthSeq)
   op = instantiateGeneric(c, op, t, t)
   result = newTree(nkCall, newSymNode(op, x.info), x, lenCall)
 
@@ -622,35 +604,11 @@ proc checkSelfAssignment(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   cond.typ = getSysType(c.g, c.info, tyBool)
   body.add genIf(c, cond, newTreeI(nkReturnStmt, c.info, newNodeI(nkEmpty, c.info)))
 
-proc genBulkCopySeq(c: var TLiftCtx; t: PType; body, x, y: PNode) =
-  ## Generates a call to nimCopySeqPayload for bulk memcpy of seq data.
-  let elemType = t.elementType
-  let sym = magicsys.getCompilerProc(c.g, "nimCopySeqPayload")
-  if sym == nil:
-    localError(c.g.config, c.info, "system module needs: nimCopySeqPayload")
-    return
-  var sizeOf = genBuiltin(c, mSizeOf, "sizeof", newNodeIT(nkType, c.info, elemType))
-  sizeOf.typ = getSysType(c.g, c.info, tyInt)
-  var alignOf = genBuiltin(c, mAlignOf, "alignof", newNodeIT(nkType, c.info, elemType))
-  alignOf.typ = getSysType(c.g, c.info, tyInt)
-  let call = newNodeI(nkCall, c.info)
-  call.add newSymNode(sym)
-  call.add newTreeIT(nkAddr, c.info, makePtrType(c.fn, x.typ, c.idgen), x)
-  call.add newTreeIT(nkAddr, c.info, makePtrType(c.fn, y.typ, c.idgen), y)
-  call.add sizeOf
-  call.add alignOf
-  call.typ = sym.typ.returnType
-  body.add call
-
 proc fillSeqOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   case c.kind
   of attachedDup:
-    let bulkCopy = supportsCopyMem(t.elementType)
-    body.add setLenSeqCall(c, t, x, y, noinit = bulkCopy)
-    if bulkCopy:
-      genBulkCopySeq(c, t, body, x, y)
-    else:
-      forallElements(c, t, body, x, y)
+    body.add setLenSeqCall(c, t, x, y)
+    forallElements(c, t, body, x, y)
   of attachedAsgn, attachedDeepCopy:
     # we generate:
     # if x.p == y.p:
@@ -659,14 +617,9 @@ proc fillSeqOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
     # var i = 0
     # while i < y.len: dest[i] = y[i]; inc(i)
     # This is usually more efficient than a destroy/create pair.
-    # For trivially copyable types, use bulk copyMem instead of element loop.
     checkSelfAssignment(c, t, body, x, y)
-    let bulkCopy = supportsCopyMem(t.elementType)
-    body.add setLenSeqCall(c, t, x, y, noinit = bulkCopy)
-    if bulkCopy:
-      genBulkCopySeq(c, t, body, x, y)
-    else:
-      forallElements(c, t, body, x, y)
+    body.add setLenSeqCall(c, t, x, y)
+    forallElements(c, t, body, x, y)
   of attachedSink:
     let moveCall = genBuiltin(c, mMove, "move", x)
     moveCall.add y
@@ -711,11 +664,6 @@ proc useSeqOrStrOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
       doAssert t.asink != nil
       body.add newHookCall(c, t.asink, x, y)
   of attachedDestructor:
-    when defined(icDbg):
-      if t.destructor == nil:
-        echo "MISSING destructor: ", typeToString(t), " kind=", t.kind,
-          " itemId=", t.itemId, " uniqueId=", t.uniqueId, " state=", t.state,
-          " owner=", (if t.owner != nil: t.owner.name.s else: "nil")
     doAssert t.destructor != nil
     body.add destructorCall(c, t.destructor, x)
   of attachedTrace:
@@ -737,18 +685,11 @@ proc fillStrOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   of attachedAsgn, attachedDeepCopy, attachedDup:
     body.add callCodegenProc(c.g, "nimAsgnStrV2", c.info, genAddr(c, x), y)
   of attachedSink:
-    if c.g.config.usesSso():
-      # SmallString: destroy old dst, then bit-copy src (no rc increment — this is a move).
-      # No .p aliasing check needed; rc-based destroy handles COW sharing correctly.
-      doAssert t.destructor != nil
-      body.add destructorCall(c, t.destructor, x)
-      body.add newAsgnStmt(x, y)
-    else:
-      let moveCall = genBuiltin(c, mMove, "move", x)
-      moveCall.add y
-      doAssert t.destructor != nil
-      moveCall.add destructorCall(c, t.destructor, x)
-      body.add moveCall
+    let moveCall = genBuiltin(c, mMove, "move", x)
+    moveCall.add y
+    doAssert t.destructor != nil
+    moveCall.add destructorCall(c, t.destructor, x)
+    body.add moveCall
   of attachedDestructor:
     body.add genBuiltin(c, mDestroy, "destroy", x)
   of attachedTrace:
@@ -780,43 +721,14 @@ proc atomicRefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
     dest[] = source
     decRef tmp
 
-  For YRC the write barrier is more complicated still and must be:
-
-    let tmp = dest
-    # assignment must come first so that the collector sees the most-recent graph:
-    atomic: dest[] = source
-    # Then teach the cycle collector about the changes edge (these use locks, see yrc.nim):
-    incRef source
-    decRef tmp
-
-  This is implemented as a single runtime call (nimAsgnYrc / nimSinkYrc).
   ]#
   var actions = newNodeI(nkStmtList, c.info)
   let elemType = t.elementType
 
   createTypeBoundOps(c.g, c.c, elemType, c.info, c.idgen)
+  let isCyclic = c.g.config.selectedGC == gcOrc and types.canFormAcycle(c.g, elemType)
 
-  # YRC uses dedicated runtime procs for the entire write barrier:
-  if c.g.config.selectedGC == gcYrc:
-    let desc =
-      if isFinal(elemType):
-        let ti = genBuiltin(c, mGetTypeInfoV2, "getTypeInfoV2", newNodeIT(nkType, x.info, elemType))
-        ti.typ = getSysType(c.g, c.info, tyPointer)
-        ti
-      else:
-        newNodeIT(nkNilLit, c.info, getSysType(c.g, c.info, tyPointer))
-    case c.kind
-    of attachedAsgn, attachedDup:
-      body.add callCodegenProc(c.g, "nimAsgnYrc", c.info, genAddr(c, x), y, desc)
-      return
-    of attachedSink:
-      body.add callCodegenProc(c.g, "nimSinkYrc", c.info, genAddr(c, x), y, desc)
-      return
-    else: discard # fall through for destructor, trace, wasMoved
-
-  let isCyclic = c.g.config.selectedGC in {gcOrc, gcYrc} and types.canFormAcycle(c.g, elemType)
-
-  let isInheritableAcyclicRef = c.g.config.selectedGC in {gcOrc, gcYrc} and
+  let isInheritableAcyclicRef = c.g.config.selectedGC == gcOrc and
                       (not isPureObject(elemType)) and
                       tfAcyclic in skipTypes(elemType, abstractInst+{tyOwned}-{tyTypeDesc}).flags
   # dynamic Acyclic refs need to use dyn decRef
@@ -898,26 +810,7 @@ proc atomicClosureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   let xenv = genBuiltin(c, mAccessEnv, "accessEnv", x)
   xenv.typ = getSysType(c.g, c.info, tyPointer)
 
-  # Closures are (fnPtr, env) pairs. nimAsgnYrc/nimSinkYrc handle the env pointer
-  # (atomic store + buffered inc/dec). We also need newAsgnStmt to copy the fnPtr.
-  if c.g.config.selectedGC == gcYrc:
-    let nilDesc = newNodeIT(nkNilLit, c.info, getSysType(c.g, c.info, tyPointer))
-    let yenv = genBuiltin(c, mAccessEnv, "accessEnv", y)
-    yenv.typ = getSysType(c.g, c.info, tyPointer)
-    case c.kind
-    of attachedAsgn, attachedDup:
-      # nimAsgnYrc: save old env, atomic store new env, inc new env, dec old env
-      body.add callCodegenProc(c.g, "nimAsgnYrc", c.info, genAddr(c, xenv), yenv, nilDesc)
-      # Raw struct copy to also update the function pointer (env write is redundant but benign)
-      body.add newAsgnStmt(x, y)
-      return
-    of attachedSink:
-      body.add callCodegenProc(c.g, "nimSinkYrc", c.info, genAddr(c, xenv), yenv, nilDesc)
-      body.add newAsgnStmt(x, y)
-      return
-    else: discard # fall through for destructor, trace, wasMoved
-
-  let isCyclic = c.g.config.selectedGC in {gcOrc, gcYrc}
+  let isCyclic = c.g.config.selectedGC == gcOrc
   let tmp =
     if isCyclic and c.kind in {attachedAsgn, attachedSink, attachedDup}:
       declareTempOf(c, body, xenv)
@@ -950,6 +843,7 @@ proc atomicClosureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
       body.add genIf(c, cond, actions)
     else:
       body.add genIf(c, yenv, callCodegenProc(c.g, "nimIncRef", c.info, yenv))
+
       body.add genIf(c, cond, actions)
       body.add newAsgnStmt(x, y)
   of attachedDup:
@@ -1034,7 +928,7 @@ proc closureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
     call[1] = y
     body.add newAsgnStmt(x, call)
   elif (optOwnedRefs in c.g.config.globalOptions and
-      optRefCheck in c.g.config.options) or c.g.config.selectedGC in {gcArc, gcAtomicArc, gcOrc, gcYrc}:
+      optRefCheck in c.g.config.options) or c.g.config.selectedGC in {gcArc, gcAtomicArc, gcOrc}:
     let xx = genBuiltin(c, mAccessEnv, "accessEnv", x)
     xx.typ = getSysType(c.g, c.info, tyPointer)
     case c.kind
@@ -1085,20 +979,11 @@ proc ownedClosureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
 proc fillBody(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   case t.kind
   of tyNone, tyEmpty, tyVoid: discard
-  of tyUncheckedArray:
-    # An UncheckedArray has no known length, so it cannot be copied, moved or
-    # destroyed as a value: it only ever lives behind a pointer and its bytes
-    # are managed manually (element ops for seqs/strings go through the
-    # seq/string hooks, which know the length). Emitting `x = y` for it (as the
-    # pointer-like group below does) produces an assignment of an unsized array,
-    # which the C backend cannot lower (genAssignment: tyUncheckedArray). So all
-    # value hooks for it are no-ops.
-    discard
   of tyPointer, tySet, tyBool, tyChar, tyEnum, tyInt..tyUInt64, tyCstring,
-      tyPtr, tyVar, tyLent:
+      tyPtr, tyUncheckedArray, tyVar, tyLent:
     defaultOp(c, t, body, x, y)
   of tyRef:
-    if c.g.config.selectedGC in {gcArc, gcOrc, gcYrc, gcAtomicArc}:
+    if c.g.config.selectedGC in {gcArc, gcOrc, gcAtomicArc}:
       atomicRefOp(c, t, body, x, y)
     elif (optOwnedRefs in c.g.config.globalOptions and
         optRefCheck in c.g.config.options):
@@ -1107,7 +992,7 @@ proc fillBody(c: var TLiftCtx; t: PType; body, x, y: PNode) =
       defaultOp(c, t, body, x, y)
   of tyProc:
     if t.callConv == ccClosure:
-      if c.g.config.selectedGC in {gcArc, gcOrc, gcYrc, gcAtomicArc}:
+      if c.g.config.selectedGC in {gcArc, gcOrc, gcAtomicArc}:
         atomicClosureOp(c, t, body, x, y)
       else:
         closureOp(c, t, body, x, y)
@@ -1168,12 +1053,19 @@ proc fillBody(c: var TLiftCtx; t: PType; body, x, y: PNode) =
       elif tfUnion in t.flags: # bug #25236
         defaultOp(c, t, body, x, y)
       else:
-        if not considerInferDupFromCopy(c, t, body, x, y):
+        if c.kind == attachedDup:
+          var op2 = getAttachedOp(c.g, t, attachedAsgn)
+          if op2 != nil and sfOverridden in op2.flags:
+            #markUsed(c.g.config, c.info, op, c.g.usageSym)
+            onUse(c.info, op2)
+            body.add newHookCall(c, t.assignment, x, y)
+          else:
+            fillBodyObjT(c, t, body, x, y)
+        else:
           fillBodyObjT(c, t, body, x, y)
   of tyDistinct:
     if not considerUserDefinedOp(c, t, body, x, y):
-      if not considerInferDupFromCopy(c, t, body, x, y):
-        fillBody(c, t.elementType, body, x, y)
+      fillBody(c, t.elementType, body, x, y)
   of tyTuple:
     fillBodyTup(c, t, body, x, y)
   of tyVarargs, tyOpenArray:
@@ -1220,7 +1112,7 @@ proc symDupPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttache
 
   result.typ.addParam src
 
-  if g.config.selectedGC in {gcOrc, gcYrc} and
+  if g.config.selectedGC == gcOrc and
     cyclicType(g, typ.skipTypes(abstractInst)):
     let cycleParam = newSym(skParam, getIdent(g.cache, "cyclic"),
                             idgen, result, info)
@@ -1235,7 +1127,6 @@ proc symDupPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttache
   n[resultPos] = newSymNode(res)
   result.ast = n
   incl result.flagsImpl, {sfFromGeneric, sfGeneratedOp}
-  setHookDisamb(g, result, AttachedOpToStr[kind], typ)
 
 proc symPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttachedOp;
               info: TLineInfo; idgen: IdGenerator; isDiscriminant = false): PSym =
@@ -1248,7 +1139,7 @@ proc symPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttachedOp
   let src = newSym(skParam, getIdent(g.cache, if kind == attachedTrace: "env" else: "src"),
                    idgen, result, info)
 
-  if kind == attachedDestructor and g.config.selectedGC in {gcArc, gcOrc, gcYrc, gcAtomicArc} and
+  if kind == attachedDestructor and g.config.selectedGC in {gcArc, gcOrc, gcAtomicArc} and
      ((g.config.isDefined("nimPreviewNonVarDestructor") and not isDiscriminant) or (typ.kind in {tyRef, tyString, tySequence})):
     dest.typ = typ
   else:
@@ -1264,7 +1155,7 @@ proc symPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttachedOp
   if kind notin {attachedDestructor, attachedWasMoved}:
     result.typ.addParam src
 
-  if kind == attachedAsgn and g.config.selectedGC in {gcOrc, gcYrc} and
+  if kind == attachedAsgn and g.config.selectedGC == gcOrc and
       cyclicType(g, typ.skipTypes(abstractInst)):
     let cycleParam = newSym(skParam, getIdent(g.cache, "cyclic"),
                             idgen, result, info)
@@ -1282,10 +1173,6 @@ proc symPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttachedOp
   if kind == attachedWasMoved:
     incl result.flagsImpl, sfNoSideEffect
     incl result.typ, tfNoSideEffect
-  if not isDiscriminant:
-    # discriminant destructors derive their body from the enclosing object
-    # AND the selected field; their key is set at the call site
-    setHookDisamb(g, result, AttachedOpToStr[kind], typ)
 
 proc genTypeFieldCopy(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   let xx = genBuiltin(c, mAccessTypeField, "accessTypeField", x)
@@ -1297,17 +1184,7 @@ proc genTypeFieldCopy(c: var TLiftCtx; t: PType; body, x, y: PNode) =
 proc produceSym(g: ModuleGraph; c: PContext; typ: PType; kind: TTypeAttachedOp;
               info: TLineInfo; idgen: IdGenerator): PSym =
   if typ.kind == tyDistinct:
-    # For =dup, if the distinct type has a user-defined =copy, don't delegate
-    # to the base type. Instead fall through to the normal produceSym logic
-    # so that fillBody -> considerInferDupFromCopy can synthesize =dup from =copy.
-    if kind == attachedDup:
-      let copyOp = getAttachedOp(g, typ, attachedAsgn)
-      if copyOp != nil and sfOverridden in copyOp.flags:
-        discard "fall through to normal produceSym logic"
-      else:
-        return produceSymDistinctType(g, c, typ, kind, info, idgen)
-    else:
-      return produceSymDistinctType(g, c, typ, kind, info, idgen)
+    return produceSymDistinctType(g, c, typ, kind, info, idgen)
 
   result = getAttachedOp(g, typ, kind)
   if result == nil:
@@ -1336,22 +1213,14 @@ proc produceSym(g: ModuleGraph; c: PContext; typ: PType; kind: TTypeAttachedOp;
   else:
     var tk: TTypeKind
     var skipped: PType = nil
-    if g.config.selectedGC in {gcArc, gcOrc, gcYrc, gcHooks, gcAtomicArc}:
+    if g.config.selectedGC in {gcArc, gcOrc, gcHooks, gcAtomicArc}:
       skipped = skipTypes(typ, {tyOrdinal, tyRange, tyInferred, tyGenericInst, tyStatic, tyAlias, tySink})
       tk = skipped.kind
     else:
       tk = tyNone # no special casing for strings and seqs
     case tk
     of tySequence:
-      let needsYrcLock = g.config.selectedGC == gcYrc and
-         kind in {attachedDestructor, attachedSink, attachedAsgn, attachedDeepCopy, attachedDup} and
-         types.canFormAcycle(g, skipped.elementType)
-      # YRC: topology-changing seq ops must hold the mutator (read) lock
-      if needsYrcLock:
-        result.ast[bodyPos].add callCodegenProc(g, "acquireMutatorLock", info)
       fillSeqOp(a, typ, result.ast[bodyPos], d, src)
-      if needsYrcLock:
-        result.ast[bodyPos].add callCodegenProc(g, "releaseMutatorLock", info)
     of tyString:
       fillStrOp(a, typ, result.ast[bodyPos], d, src)
     else:
@@ -1378,7 +1247,6 @@ proc produceDestructorForDiscriminator*(g: ModuleGraph; typ: PType; field: PSym,
   assert(typ.skipTypes({tyAlias, tyGenericInst}).kind == tyObject)
   # discrimantor assignments needs pointers to destroy fields; alas, we cannot use non-var destructor here
   result = symPrototype(g, field.typ, typ.owner, attachedDestructor, info, idgen, isDiscriminant = true)
-  setHookDisamb(g, result, "=destroy¦" & field.name.s & "¦" & $field.position, typ)
   var a = TLiftCtx(info: info, g: g, kind: attachedDestructor, asgnForType: typ, idgen: idgen,
                    fn: result)
   a.asgnForType = typ
@@ -1467,7 +1335,7 @@ proc createTypeBoundOps(g: ModuleGraph; c: PContext; orig: PType; info: TLineInf
 
   # we do not generate '=trace' procs if we
   # have the cycle detection disabled, saves code size.
-  let lastAttached = if g.config.selectedGC in {gcOrc, gcYrc}: attachedTrace
+  let lastAttached = if g.config.selectedGC == gcOrc: attachedTrace
                      else: attachedSink
 
   # bug #15122: We need to produce all prototypes before entering the

compiler/lineinfos.nim

@@ -93,14 +93,10 @@ type
     warnBareExcept = "BareExcept",
     warnImplicitDefaultValue = "ImplicitDefaultValue",
     warnIgnoredSymbolInjection = "IgnoredSymbolInjection",
-    warnStdPrefix = "StdPrefix",
-    warnUnknownNotes = "UnknownNotes",
-    warnLongLiterals = "LongLiterals",
+    warnStdPrefix = "StdPrefix"
+    warnUnknownNotes = "UnknownNotes"
     warnUser = "User",
     warnGlobalVarConstructorTemporary = "GlobalVarConstructorTemporary",
-    warnImplicitRangeConversion = "ImplicitRangeConversion",
-    warnSystemRangeConversion = "SystemRangeConversion",
-    warnInvalidCmpOp = "InvalidCmpOp",
     # hints
     hintSuccess = "Success", hintSuccessX = "SuccessX",
     hintCC = "CC",
@@ -206,12 +202,8 @@ const
     warnIgnoredSymbolInjection: "$1",
     warnStdPrefix: "$1 needs the 'std' prefix",
     warnUnknownNotes: "$1",
-    warnLongLiterals: "$1",
     warnUser: "$1",
     warnGlobalVarConstructorTemporary: "global variable '$1' initialization requires a temporary variable",
-    warnImplicitRangeConversion: "implicit range conversion $1",
-    warnSystemRangeConversion: "implicit range conversion $1",
-    warnInvalidCmpOp: "$1",
     hintSuccess: "operation successful: $#",
     # keep in sync with `testament.isSuccess`
     hintSuccessX: "$build\n$loc lines; ${sec}s; $mem; proj: $project; out: $output",
@@ -266,9 +258,9 @@ type
 
 proc computeNotesVerbosity(): array[0..3, TNoteKinds] =
   result = default(array[0..3, TNoteKinds])
-  result[3] = {low(TNoteKind)..high(TNoteKind)} - {warnObservableStores, warnResultUsed, warnAnyEnumConv, warnBareExcept, warnStdPrefix, warnSystemRangeConversion}
+  result[3] = {low(TNoteKind)..high(TNoteKind)} - {warnObservableStores, warnResultUsed, warnAnyEnumConv, warnBareExcept, warnStdPrefix}
   result[2] = result[3] - {hintStackTrace, hintExtendedContext, hintDeclaredLoc, hintProcessingStmt}
-  result[1] = result[2] - {warnImplicitRangeConversion, warnProveField, warnProveIndex,
+  result[1] = result[2] - {warnProveField, warnProveIndex,
     warnGcUnsafe, hintPath, hintDependency, hintCodeBegin, hintCodeEnd,
     hintSource, hintGlobalVar, hintGCStats, hintMsgOrigin, hintPerformance}
   result[0] = result[1] - {hintSuccessX, hintSuccess, hintConf,

compiler/linter.nim

@@ -95,7 +95,7 @@ proc nep1CheckDefImpl(conf: ConfigRef; info: TLineInfo; s: PSym; k: TSymKind) =
 template styleCheckDef*(ctx: PContext; info: TLineInfo; sym: PSym; k: TSymKind) =
   ## Check symbol definitions adhere to NEP1 style rules.
   if optStyleCheck in ctx.config.options and # ignore if styleChecks are off
-     {optStyleHint, optStyleError, optStyleWarning} * ctx.config.globalOptions != {} and # check only if hint/error/warning is enabled
+     {optStyleHint, optStyleError} * ctx.config.globalOptions != {} and # check only if hint/error is enabled
      hintName in ctx.config.notes and # ignore if name checks are not requested
      ctx.config.belongsToProjectPackageMaybeNil(getModule(ctx.graph, info.fileIndex)) and # ignore foreign packages
      optStyleUsages notin ctx.config.globalOptions and # ignore if requested to only check name usage
@@ -136,7 +136,7 @@ proc styleCheckUseImpl(conf: ConfigRef; info: TLineInfo; s: PSym) =
 
 template styleCheckUse*(ctx: PContext; info: TLineInfo; sym: PSym) =
   ## Check symbol uses match their definition's style.
-  if {optStyleHint, optStyleError, optStyleWarning} * ctx.config.globalOptions != {} and # ignore if styleChecks are off
+  if {optStyleHint, optStyleError} * ctx.config.globalOptions != {} and # ignore if styleChecks are off
      hintName in ctx.config.notes and # ignore if name checks are not requested
      ctx.config.belongsToProjectPackageMaybeNil(getModule(ctx.graph, info.fileIndex)) and # ignore foreign packages
      sym.kind != skTemp and # ignore temporary variables created by the compiler
@@ -152,7 +152,7 @@ proc checkPragmaUseImpl(conf: ConfigRef; info: TLineInfo; w: TSpecialWord; pragm
 template checkPragmaUse*(ctx: PContext; info: TLineInfo; w: TSpecialWord; pragmaName: string, sym: PSym) =
   ## Check builtin pragma uses match their definition's style.
   ## Note: This only applies to builtin pragmas, not user pragmas.
-  if {optStyleHint, optStyleError, optStyleWarning} * ctx.config.globalOptions != {} and # ignore if styleChecks are off
+  if {optStyleHint, optStyleError} * ctx.config.globalOptions != {} and # ignore if styleChecks are off
      hintName in ctx.config.notes and # ignore if name checks are not requested
      ctx.config.belongsToProjectPackageMaybeNil(getModule(ctx.graph, info.fileIndex)): # ignore foreign packages
     checkPragmaUseImpl(ctx.config, info, w, pragmaName)

compiler/llstream.nim

@@ -163,7 +163,7 @@ proc llReadFromStdin(s: PLLStream, buf: pointer, bufLen: int): int =
   inc(s.lineOffset)
   result = min(bufLen, s.s.len - s.rd)
   if result > 0:
-    copyMem(buf, readRawData(s.s, s.rd), result)
+    copyMem(buf, addr(s.s[s.rd]), result)
     inc(s.rd, result)
 
 proc llStreamRead*(s: PLLStream, buf: pointer, bufLen: int): int =
@@ -173,7 +173,7 @@ proc llStreamRead*(s: PLLStream, buf: pointer, bufLen: int): int =
   of llsString:
     result = min(bufLen, s.s.len - s.rd)
     if result > 0:
-      copyMem(buf, readRawData(s.s, s.rd), result)
+      copyMem(buf, addr(s.s[0 + s.rd]), result)
       inc(s.rd, result)
   of llsFile:
     result = readBuffer(s.f, buf, bufLen)

compiler/lookups.nim

@@ -378,9 +378,6 @@ proc wrongRedefinition*(c: PContext; info: TLineInfo, s: string;
                         conflictsWith: TLineInfo, note = errGenerated) =
   ## Emit a redefinition error if in non-interactive mode
   if c.config.cmd != cmdInteractive:
-    when defined(icDbgRefc):
-      echo "[icRedef] ", s
-      echo getStackTrace()
     localError(c.config, info, note,
       "redefinition of '$1'; previous declaration here: $2" %
       [s, c.config $ conflictsWith])
@@ -415,6 +412,8 @@ proc addDecl*(c: PContext, sym: PSym) {.inline.} =
 proc addPrelimDecl*(c: PContext, sym: PSym) =
   discard c.currentScope.addUniqueSym(sym)
 
+from ic / ic import addHidden
+
 proc addInterfaceDeclAux(c: PContext, sym: PSym) =
   ## adds symbol to the module for either private or public access.
   if sfExported in sym.flags:
@@ -423,6 +422,8 @@ proc addInterfaceDeclAux(c: PContext, sym: PSym) =
     else: internalError(c.config, sym.info, "addInterfaceDeclAux")
   elif sym.kind in ExportableSymKinds and c.module != nil and isTopLevelInsideDeclaration(c, sym):
     strTableAdd(semtabAll(c.graph, c.module), sym)
+    if c.config.symbolFiles != disabledSf:
+      addHidden(c.encoder, c.packedRepr, sym)
 
 proc addInterfaceDeclAt*(c: PContext, scope: PScope, sym: PSym) =
   ## adds a symbol on the scope and the interface if appropriate
@@ -462,15 +463,6 @@ proc openShadowScope*(c: PContext) =
                           symbols: initStrTable(),
                           depthLevel: c.scopeDepth)
 
-proc rememberShadowDefs*(c: PContext) =
-  ## bug #25693: a template/macro operand's local definitions are sem-checked in
-  ## a shadow scope that is then discarded. Record those definitions so that a
-  ## later re-emission (e.g. a captured `typed` fragment expanded more than once)
-  ## can be detected as a redefinition rather than silently miscompiled.
-  for s in c.currentScope.symbols:
-    if s.kind in {skVar, skLet, skForVar} and {sfGenSym, sfWasGenSym} * s.flags == {}:
-      c.shadowDiscardedDefs.incl s.id
-
 proc closeShadowScope*(c: PContext) =
   ## closes the shadow scope, but doesn't merge any of the symbols
   ## Does not check for unused symbols or missing forward decls since a macro

compiler/lowerings.nim

@@ -207,7 +207,7 @@ proc lookupInRecord(n: PNode, id: ItemId): PSym =
         if result != nil: return
       else: discard
   of nkSym:
-    if matchesDerivedFieldId(n.sym.itemId, id): result = n.sym
+    if n.sym.itemId.module == id.module and n.sym.itemId.item == -abs(id.item): result = n.sym
   else: discard
 
 proc addField*(obj: PType; s: PSym; cache: IdentCache; idgen: IdGenerator): PSym =
@@ -215,7 +215,7 @@ proc addField*(obj: PType; s: PSym; cache: IdentCache; idgen: IdGenerator): PSym
   # This is hacky but the clean solution is much more complex than it looks.
   var field = newSym(skField, getIdent(cache, s.name.s & $obj.n.len),
                      idgen, s.owner, s.info, s.options)
-  field.itemId = derivedFieldId(s.itemId)
+  field.itemId = ItemId(module: s.itemId.module, item: -s.itemId.item)
   let t = skipIntLit(s.typ, idgen)
   field.typ = t
   if s.kind in {skLet, skVar, skField, skForVar}:
@@ -235,7 +235,7 @@ proc addUniqueField*(obj: PType; s: PSym; cache: IdentCache; idgen: IdGenerator)
   if result == nil:
     var field = newSym(skField, getIdent(cache, s.name.s & $obj.n.len), idgen,
                        s.owner, s.info, s.options)
-    field.itemId = derivedFieldId(s.itemId)
+    field.itemId = ItemId(module: s.itemId.module, item: -s.itemId.item)
     let t = skipIntLit(s.typ, idgen)
     field.typ = t
     assert t.kind != tyTyped

compiler/magicsys.nim

@@ -11,7 +11,7 @@
 
 import
   ast, msgs, platform, idents,
-  modulegraphs, lineinfos, types
+  modulegraphs, lineinfos
 
 export createMagic
 
@@ -134,7 +134,7 @@ proc getNimScriptSymbol*(g: ModuleGraph; name: string): PSym =
 proc resetNimScriptSymbols*(g: ModuleGraph) = g.exposed = initStrTable()
 
 proc getMagicEqSymForType*(g: ModuleGraph; t: PType; info: TLineInfo): PSym =
-  case t.skipTypes(abstractRange).kind
+  case t.kind
   of tyInt,  tyInt8, tyInt16, tyInt32, tyInt64,
      tyUInt, tyUInt8, tyUInt16, tyUInt32, tyUInt64:
     result = getSysMagic(g, info, "==", mEqI)

compiler/main.nim

@@ -26,10 +26,11 @@ import
 when defined(nimPreviewSlimSystem):
   import std/[syncio, assertions]
 
+import ic / [cbackend, integrity, navigator, ic]
+
 import ../dist/checksums/src/checksums/sha1
 
 import pipelines
-from icconfig import produceIcConfig
 
 when not defined(nimKochBootstrap):
   import nifbackend
@@ -98,6 +99,14 @@ proc commandCheck(graph: ModuleGraph) =
   setPipeLinePass(graph, SemPass)
   compilePipelineProject(graph)
 
+  if conf.symbolFiles != disabledSf:
+    case conf.ideCmd
+    of ideDef: navDefinition(graph)
+    of ideUse: navUsages(graph)
+    of ideDus: navDefusages(graph)
+    else: discard
+    writeRodFiles(graph)
+
 when not defined(leanCompiler):
   proc commandDoc2(graph: ModuleGraph; ext: string) =
     handleDocOutputOptions graph.config
@@ -164,7 +173,15 @@ proc commandCompileToC(graph: ModuleGraph) =
   compilePipelineProject(graph)
   if graph.config.errorCounter > 0:
     return # issue #9933
-  cgenWriteModules(graph.backend, conf)
+  if conf.symbolFiles == disabledSf:
+    cgenWriteModules(graph.backend, conf)
+  else:
+    if isDefined(conf, "nimIcIntegrityChecks"):
+      checkIntegrity(graph)
+    generateCode(graph)
+    # graph.backend can be nil under IC when nothing changed at all:
+    if graph.backend != nil:
+      cgenWriteModules(graph.backend, conf)
   if conf.cmd != cmdTcc and graph.backend != nil:
     extccomp.callCCompiler(conf)
     # for now we do not support writing out a .json file with the build instructions when HCR is on
@@ -224,6 +241,10 @@ proc commandScan(cache: IdentCache, config: ConfigRef) =
   else:
     rawMessage(config, errGenerated, "cannot open file: " & f.string)
 
+proc commandView(graph: ModuleGraph) =
+  let f = toAbsolute(mainCommandArg(graph.config), AbsoluteDir getCurrentDir()).addFileExt(RodExt)
+  rodViewer(f, graph.config, graph.cache)
+
 const
   PrintRopeCacheStats = false
 
@@ -321,6 +342,8 @@ proc mainCommand*(graph: ModuleGraph) =
   case conf.cmd
   of cmdBackends:
     compileToBackend()
+    when BenchIC:
+      echoTimes graph.packed
   of cmdTcc:
     when hasTinyCBackend:
       extccomp.setCC(conf, "tcc", unknownLineInfo)
@@ -420,14 +443,9 @@ proc mainCommand*(graph: ModuleGraph) =
     # cmdM uses NIF files, not ROD files
     graph.config.symbolFiles = disabledSf
     setUseIc(true)
-    # vtable dispatch needs a whole-program vtable layout, which the
-    # per-module compilation model cannot provide (yet); methods dispatch
-    # through the classic if-chain dispatchers instead
-    excl conf.features, Feature.vtables
     commandCheck(graph)
   of cmdNifC:
     setUseIc(true)
-    excl conf.features, Feature.vtables
     # Generate C code from NIF files
     wantMainModule(conf)
     setOutFile(conf)
@@ -440,14 +458,13 @@ proc mainCommand*(graph: ModuleGraph) =
       commandIc(conf)
     else:
       rawMessage(conf, errGenerated, "nim deps not available in bootstrap build")
-  of cmdIcConfig:
-    # Produce the precompiled config artifact for `nim ic` (config already
-    # parsed by the normal pipeline); a separate process spawned by the driver.
-    wantMainModule(conf)
-    produceIcConfig(conf)
   of cmdParse:
     wantMainModule(conf)
     discard parseFile(conf.projectMainIdx, cache, conf)
+  of cmdRod:
+    wantMainModule(conf)
+    commandView(graph)
+    #msgWriteln(conf, "Beware: Indentation tokens depend on the parser's state!")
   of cmdInteractive: commandInteractive(graph)
   of cmdNimscript:
     if conf.projectIsCmd or conf.projectIsStdin: discard
@@ -461,14 +478,7 @@ proc mainCommand*(graph: ModuleGraph) =
   of cmdUnknown, cmdNone, cmdIdeTools:
     rawMessage(conf, errGenerated, "invalid command: " & conf.command)
 
-  if conf.errorCounter == 0 and conf.cmd notin {cmdTcc, cmdDump, cmdNop, cmdM} and
-      not (conf.cmd == cmdNifC and conf.icBackendStage.len > 0):
-    # The IC build runs hundreds of internal per-module child processes — the
-    # frontend `nim m` (cmdM) and the per-module backend stages (cg/emit/merge/
-    # link). Each would print a `[SuccessX]` summary that is pure noise (and
-    # misleading: `out: unknownOutput`, or `out: <the whole compiler>` for a
-    # step that only wrote one `.c.nif`/`.c`). The driving `nim ic` (and koch)
-    # reports the real result.
+  if conf.errorCounter == 0 and conf.cmd notin {cmdTcc, cmdDump, cmdNop}:
     if optProfileVM in conf.globalOptions:
       echo conf.dump(conf.vmProfileData)
     genSuccessX(conf)

compiler/mangleutils.nim

@@ -53,29 +53,7 @@ proc mangleParamExt*(s: PSym): string =
   result.addInt s.position
 
 proc mangleProcNameExt*(graph: ModuleGraph, s: PSym): string =
-  # The disambiguator comes first and the module suffix LAST, so the suffix is
-  # a strippable trailing token: content-addressed cross-module merging chops
-  # everything from the final `__` to recover a mint-site-independent name.
-  if s.itemId.isBackendMinted:
-    # A symbol minted during IC codegen (`idGeneratorForBackend`): its idgen
-    # starts with an EMPTY per-name disamb table, so its `disamb` restarts at 0
-    # and collides with same-named sem-time symbols loaded from NIFs (two
-    # `=destroy` hooks both mangling to `_u2` → "conflicting types for ..." in
-    # the generated C). These symbols never cross a process boundary (nifc
-    # lifts, emits and compiles them in one run), so the per-module-unique
-    # item id is a safe and deterministic discriminator; the `_c` marker keeps
-    # the namespace disjoint from `_u<disamb>`.
-    result = "_c"
-    result.addInt s.itemId.item
-  else:
-    result = "_u"
-    # Use `disamb` rather than `itemId.item`: under incremental compilation a
-    # symbol loaded from a NIF file gets a fresh, load-order-dependent `itemId.item`
-    # (from the per-module symbol counter), which is neither stable across the
-    # processes that compile vs. use a module nor guaranteed distinct from another
-    # loaded symbol's. `disamb` is assigned deterministically per (module, name)
-    # and, together with the already-prepended mangled name, yields a unique and
-    # stable C identifier.
-    result.addInt s.disamb
-  result.add "__"
+  result = "__"
   result.add graph.ifaces[s.itemId.module].uniqueName
+  result.add "_u"
+  result.addInt s.itemId.item # s.disamb #

compiler/modulegraphs.nim

@@ -11,9 +11,10 @@
 ## represents a complete Nim project. Single modules can either be kept in RAM
 ## or stored in a rod-file.
 
-import std/[intsets, tables, hashes, strtabs, os, strutils, parseutils, sets]
+import std/[intsets, tables, hashes, strtabs, os, strutils, parseutils]
 import ../dist/checksums/src/checksums/md5
 import ast, astalgo, options, lineinfos,idents, btrees, ropes, msgs, pathutils, packages, suggestsymdb
+import ic / [packed_ast, ic]
 
 when not defined(nimKochBootstrap):
   import ast2nif
@@ -27,12 +28,16 @@ when defined(nimPreviewSlimSystem):
 type
   SigHash* = distinct MD5Digest
 
+  LazySym* = object
+    id*: FullId
+    sym*: PSym
+
   Iface* = object       ## data we don't want to store directly in the
                         ## ast.PSym type for s.kind == skModule
     module*: PSym       ## module this "Iface" belongs to
-    converters*: seq[PSym]
-    patterns*: seq[PSym]
-    pureEnums*: seq[PSym]
+    converters*: seq[LazySym]
+    patterns*: seq[LazySym]
+    pureEnums*: seq[LazySym]
     interf: TStrTable
     interfHidden: TStrTable
     uniqueName*: Rope
@@ -41,6 +46,20 @@ type
     opNot*, opContains*, opLe*, opLt*, opAnd*, opOr*, opIsNil*, opEq*: PSym
     opAdd*, opSub*, opMul*, opDiv*, opLen*: PSym
 
+  FullId* = object
+    module*: int
+    packed*: PackedItemId
+
+  LazyType* = object
+    id*: FullId
+    typ*: PType
+
+  LazyInstantiation* = object
+    module*: int
+    sym*: FullId
+    concreteTypes*: seq[FullId]
+    inst*: PInstantiation
+
   PipelinePass* = enum
     NonePass
     SemPass
@@ -56,55 +75,21 @@ type
 
   ModuleGraph* {.acyclic.} = ref object
     ifaces*: seq[Iface]  ## indexed by int32 fileIdx
+    packed*: PackedModuleGraph
+    encoders*: seq[PackedEncoder]
 
-    typeInstCache*: Table[ItemId, seq[PType]] # A symbol's ItemId.
-    procInstCache*: Table[ItemId, seq[PInstantiation]] # A symbol's ItemId.
-    attachedOps*: array[TTypeAttachedOp, Table[ItemId, PSym]] # Type ID, destructors, etc.
+    typeInstCache*: Table[ItemId, seq[LazyType]] # A symbol's ItemId.
+    procInstCache*: Table[ItemId, seq[LazyInstantiation]] # A symbol's ItemId.
+    attachedOps*: array[TTypeAttachedOp, Table[ItemId, LazySym]] # Type ID, destructors, etc.
     loadedOps: array[TTypeAttachedOp, Table[string, PSym]] # This can later by unified with `attachedOps` once it's stable
     opsLog*: seq[LogEntry]
-    methodsPerGenericType*: Table[ItemId, seq[(int, PSym)]] # Type ID, attached methods
+    methodsPerGenericType*: Table[ItemId, seq[(int, LazySym)]] # Type ID, attached methods
     memberProcsPerType*: Table[ItemId, seq[PSym]] # Type ID, attached member procs (only c++, virtual,member and ctor so far).
     initializersPerType*: Table[ItemId, PNode] # Type ID, AST call to the default ctor (c++ only)
-    enumToStringProcs*: Table[ItemId, PSym]
-    loadedEnumToStringProcs: Table[string, PSym]
+    enumToStringProcs*: Table[ItemId, LazySym]
     emittedTypeInfo*: Table[string, FileIndex]
-    instDisambs: Table[(int, int32), ItemId] # (name id, content disamb) ->
-                                  # instance, for collision probing in
-                                  # `setInstanceDisamb`
-    icCnifFiles*: seq[string]     # `.c.nif` artifacts written by this run
-    pendingMethodReplays*: seq[PSym] # method registrations loaded under
-                                  # `nim nifc`, bucketed only after every
-                                  # module is loaded (`flushMethodReplays`)
-    icImplDeps*: IntSet           # NeedsImpl edge tracking under `nim m`:
-                                  # module ids (FileIndex) whose routine BODIES
-                                  # this compilation consumed at compile time.
-                                  # Written to the `.edges` sidecar; deps.nim
-                                  # then gates the dependent on those modules'
-                                  # IMPL cookie instead of the iface cookie, so
-                                  # e.g. `const x = dep.foo()` re-sems when foo's
-                                  # body changes. Uniform across body-access
-                                  # kinds — the iface cookie hashes signatures
-                                  # ONLY (see ast2nif.cookieSd), so every body
-                                  # consumer records an edge here: VM-compiled /
-                                  # getImpl'ed bodies (recordIcImplDep from vm/
-                                  # vmgen), expanded templates (semTemplateExpr)
-                                  # and instantiated generics (generateInstance).
-                                  # Inline iterators / `inline` procs are NOT
-                                  # tracked: they are inlined at codegen, where
-                                  # the nifc backend's NIF-mtime invalidation
-                                  # already re-codegens their users.
-    icQualIfaces*: IntSet         # module positions whose interface tables were
-                                  # populated ONLY for qualified access through a
-                                  # module re-export (`import x; export x`); the
-                                  # Iface.module stays nil so a later direct
-                                  # import still takes the full load path
-    inVMTransform*: int           # >0 while the VM compiles a routine body
-                                  # (vmgen.genProc's transformBody): hooks lifted
-                                  # there (e.g. for closure-env types of LOADED
-                                  # routines) are process-local VM artifacts —
-                                  # serializing them would embed references to
-                                  # derived env-field syms that no module defines
 
+    startupPackedConfig*: PackedConfig
     packageSyms*: TStrTable
     deps*: IntSet # the dependency graph or potentially its transitive closure.
     importDeps*: Table[FileIndex, seq[FileIndex]] # explicit import module dependencies
@@ -130,8 +115,8 @@ type
     methods*: seq[tuple[methods: seq[PSym], dispatcher: PSym]] # needs serialization!
     bucketTable*: CountTable[ItemId]
     objectTree*: Table[ItemId, seq[tuple[depth: int, value: PType]]]
-    methodsPerType*: Table[ItemId, seq[PSym]]
-    dispatchers*: seq[PSym]
+    methodsPerType*: Table[ItemId, seq[LazySym]]
+    dispatchers*: seq[LazySym]
 
     systemModule*: PSym
     sysTypes*: array[TTypeKind, PType]
@@ -146,11 +131,6 @@ type
     cacheSeqs*: Table[string, PNode] # state that is shared to support the 'macrocache' API; IC: implemented
     cacheCounters*: Table[string, BiggestInt] # IC: implemented
     cacheTables*: Table[string, BTree[string, PNode]] # IC: implemented
-    transitiveReplayActions*: seq[PNode] # macro-cache replay actions collected from
-      # the transitive import closure of a NIF-loaded module (loadTransitiveHooks);
-      # the caller (pipelines) replays them so a dependency's macrocache state — e.g.
-      # nim-serialization's flavor registration — reaches a module that imports it
-      # only indirectly. Drained per moduleFromNifFile call.
     passes*: seq[TPass]
     pipelinePass*: PipelinePass
     onDefinition*: proc (graph: ModuleGraph; s: PSym; info: TLineInfo) {.nimcall.}
@@ -166,8 +146,6 @@ type
 
     procGlobals*: seq[PNode]
     nifReplayActions*: Table[int32, seq[PNode]]  # module position -> replay actions for NIF
-    cachedMods: IntSet
-    hookClosure: IntSet # modules whose serialized hooks were already registered
 
   TPassContext* = object of RootObj # the pass's context
     idgen*: IdGenerator
@@ -190,7 +168,6 @@ proc resetForBackend*(g: ModuleGraph) =
     a.clear()
   g.methodsPerGenericType.clear()
   g.enumToStringProcs.clear()
-  g.loadedEnumToStringProcs.clear()
   g.dispatchers.setLen(0)
   g.methodsPerType.clear()
   for a in mitems(g.loadedOps):
@@ -251,55 +228,85 @@ proc strTableAdds*(g: ModuleGraph, m: PSym, s: PSym) =
   strTableAdd(semtabAll(g, m), s)
 
 proc isCachedModule(g: ModuleGraph; module: int): bool {.inline.} =
-  result = module in g.cachedMods
+  result = module < g.packed.len and g.packed[module].status == loaded
 
 proc isCachedModule*(g: ModuleGraph; m: PSym): bool {.inline.} =
   isCachedModule(g, m.position)
 
+proc simulateCachedModule(g: ModuleGraph; moduleSym: PSym; m: PackedModule) =
+  when false:
+    echo "simulating ", moduleSym.name.s, " ", moduleSym.position
+  simulateLoadedModule(g.packed, g.config, g.cache, moduleSym, m)
+
+proc initEncoder*(g: ModuleGraph; module: PSym) =
+  let id = module.position
+  if id >= g.encoders.len:
+    setLen g.encoders, id+1
+  ic.initEncoder(g.encoders[id],
+    g.packed[id].fromDisk, module, g.config, g.startupPackedConfig)
+
 type
   ModuleIter* = object
+    fromRod: bool
     modIndex: int
     ti: TIdentIter
+    rodIt: RodIter
     importHidden: bool
 
 proc initModuleIter*(mi: var ModuleIter; g: ModuleGraph; m: PSym; name: PIdent): PSym =
   assert m.kind == skModule
   mi.modIndex = m.position
+  mi.fromRod = isCachedModule(g, mi.modIndex)
   mi.importHidden = optImportHidden in m.options
-  result = initIdentIter(mi.ti, g.ifaces[mi.modIndex].interfSelect(mi.importHidden), name)
+  if mi.fromRod:
+    result = initRodIter(mi.rodIt, g.config, g.cache, g.packed, FileIndex mi.modIndex, name, mi.importHidden)
+  else:
+    result = initIdentIter(mi.ti, g.ifaces[mi.modIndex].interfSelect(mi.importHidden), name)
 
 proc nextModuleIter*(mi: var ModuleIter; g: ModuleGraph): PSym =
-  result = nextIdentIter(mi.ti, g.ifaces[mi.modIndex].interfSelect(mi.importHidden))
+  if mi.fromRod:
+    result = nextRodIter(mi.rodIt, g.packed)
+  else:
+    result = nextIdentIter(mi.ti, g.ifaces[mi.modIndex].interfSelect(mi.importHidden))
 
 iterator allSyms*(g: ModuleGraph; m: PSym): PSym =
   let importHidden = optImportHidden in m.options
-  for s in g.ifaces[m.position].interfSelect(importHidden).data:
-    if s != nil:
-      yield s
-
-proc reexportedModuleSyms*(g: ModuleGraph; m: PSym): seq[(string, string)] =
-  ## (name, NIF module suffix) of MODULE syms in `m`'s interface — these are
-  ## re-exports (`import x; export x`, added by `reexportSym`) acting as
-  ## qualifiers (`m.x.sym`). Consumed by the NIF writer; semExport does not
-  ## put them into the nkExportStmt children, so the AST walk cannot see them.
-  result = @[]
-  var seen = initIntSet()
-  for s in g.ifaces[m.position].interf.data:
-    if s != nil and s.kind == skModule and s.position != m.position and
-        not seen.containsOrIncl(s.position):
-      result.add (s.name.s, cachedModuleSuffix(g.config, FileIndex s.position))
+  if isCachedModule(g, m):
+    var rodIt: RodIter = default(RodIter)
+    var r = initRodIterAllSyms(rodIt, g.config, g.cache, g.packed, FileIndex m.position, importHidden)
+    while r != nil:
+      yield r
+      r = nextRodIter(rodIt, g.packed)
+  else:
+    for s in g.ifaces[m.position].interfSelect(importHidden).data:
+      if s != nil:
+        yield s
 
 proc someSym*(g: ModuleGraph; m: PSym; name: PIdent): PSym =
   let importHidden = optImportHidden in m.options
-  result = strTableGet(g.ifaces[m.position].interfSelect(importHidden), name)
+  if isCachedModule(g, m):
+    result = interfaceSymbol(g.config, g.cache, g.packed, FileIndex(m.position), name, importHidden)
+  else:
+    result = strTableGet(g.ifaces[m.position].interfSelect(importHidden), name)
 
 proc someSymAmb*(g: ModuleGraph; m: PSym; name: PIdent; amb: var bool): PSym =
   let importHidden = optImportHidden in m.options
-  var ti: TIdentIter = default(TIdentIter)
-  result = initIdentIter(ti, g.ifaces[m.position].interfSelect(importHidden), name)
-  if result != nil and nextIdentIter(ti, g.ifaces[m.position].interfSelect(importHidden)) != nil:
-    # another symbol exists with same name
-    amb = true
+  if isCachedModule(g, m):
+    result = nil
+    for s in interfaceSymbols(g.config, g.cache, g.packed, FileIndex(m.position), name, importHidden):
+      if result == nil:
+        # set result to the first symbol
+        result = s
+      else:
+        # another symbol found
+        amb = true
+        break
+  else:
+    var ti: TIdentIter = default(TIdentIter)
+    result = initIdentIter(ti, g.ifaces[m.position].interfSelect(importHidden), name)
+    if result != nil and nextIdentIter(ti, g.ifaces[m.position].interfSelect(importHidden)) != nil:
+      # another symbol exists with same name
+      amb = true
 
 proc systemModuleSym*(g: ModuleGraph; name: PIdent): PSym =
   result = someSym(g, g.systemModule, name)
@@ -311,116 +318,106 @@ iterator systemModuleSyms*(g: ModuleGraph; name: PIdent): PSym =
     yield r
     r = nextModuleIter(mi, g)
 
+proc resolveType(g: ModuleGraph; t: var LazyType): PType =
+  result = t.typ
+  if result == nil and isCachedModule(g, t.id.module):
+    result = loadTypeFromId(g.config, g.cache, g.packed, t.id.module, t.id.packed)
+    t.typ = result
+  assert result != nil
+
+proc resolveSym(g: ModuleGraph; t: var LazySym): PSym =
+  result = t.sym
+  if result == nil and isCachedModule(g, t.id.module):
+    result = loadSymFromId(g.config, g.cache, g.packed, t.id.module, t.id.packed)
+    t.sym = result
+  assert result != nil
+
+proc resolveInst(g: ModuleGraph; t: var LazyInstantiation): PInstantiation =
+  result = t.inst
+  if result == nil and isCachedModule(g, t.module):
+    result = PInstantiation(sym: loadSymFromId(g.config, g.cache, g.packed, t.sym.module, t.sym.packed))
+    result.concreteTypes = newSeq[PType](t.concreteTypes.len)
+    for i in 0..high(result.concreteTypes):
+      result.concreteTypes[i] = loadTypeFromId(g.config, g.cache, g.packed,
+          t.concreteTypes[i].module, t.concreteTypes[i].packed)
+    t.inst = result
+  assert result != nil
+
+proc resolveAttachedOp*(g: ModuleGraph; t: var LazySym): PSym =
+  result = t.sym
+  if result == nil:
+    result = loadSymFromId(g.config, g.cache, g.packed, t.id.module, t.id.packed)
+    t.sym = result
+  assert result != nil
+
 iterator typeInstCacheItems*(g: ModuleGraph; s: PSym): PType =
   if g.typeInstCache.contains(s.itemId):
     let x = addr(g.typeInstCache[s.itemId])
     for t in mitems(x[]):
-      yield t
+      yield resolveType(g, t)
 
 iterator procInstCacheItems*(g: ModuleGraph; s: PSym): PInstantiation =
   if g.procInstCache.contains(s.itemId):
     let x = addr(g.procInstCache[s.itemId])
     for t in mitems(x[]):
-      yield t
+      yield resolveInst(g, t)
 
 
 proc getAttachedOp*(g: ModuleGraph; t: PType; op: TTypeAttachedOp): PSym =
   ## returns the requested attached operation for type `t`. Can return nil
   ## if no such operation exists.
   if g.attachedOps[op].contains(t.itemId):
-    result = g.attachedOps[op][t.itemId]
+    result = resolveAttachedOp(g, g.attachedOps[op][t.itemId])
   elif g.config.cmd in {cmdNifC, cmdM}:
     # Fall back to key-based lookup for NIF-loaded hooks
     let key = typeKey(t, g.config, loadTypeCallback, loadSymCallback)
     result = g.loadedOps[op].getOrDefault(key)
     #echo "fallback ", key, " ", op, " ", result
-    when defined(icDbgHash):
-      if result == nil and op == attachedDestructor:
-        echo "HOOK MISS key=", key, " table.len=", g.loadedOps[op].len,
-          " kind=", t.kind, " sym=", (if t.sym != nil: t.sym.name.s else: "NIL")
-        if key.len > 10:
-          let probe = key[3 ..< min(key.len, 18)]
-          for k in g.loadedOps[op].keys:
-            if probe in k: echo "  candidate: ", k
   else:
     result = nil
 
 proc setAttachedOp*(g: ModuleGraph; module: int; t: PType; op: TTypeAttachedOp; value: PSym) =
   ## we also need to record this to the packed module.
-  # Key-based deduplication for opsLog: different type objects (e.g. canon vs
-  # orig) can have different itemIds but the same structural key.
-  let key = typeKey(t, g.config, loadTypeCallback, loadSymCallback)
-  if g.inVMTransform > 0 and g.config.cmd == cmdM:
-    # hook lifted while the VM compiles a routine body (closure-env types of
-    # loaded routines): register it for in-process lookup but keep it out of
-    # the serialized log — it is a process-local artifact whose type graph
-    # references derived env-field syms that no module's NIF defines
-    if g.loadedOps[op].getOrDefault(key) == nil:
+  if not g.attachedOps[op].contains(t.itemId):
+    let key = typeKey(t, g.config, loadTypeCallback, loadSymCallback)
+    # Use key-based deduplication for opsLog because different type objects
+    # (e.g. canon vs orig) can have different itemIds but same structural key
+    if key notin g.loadedOps[op]:
+      # Hooks should be written to the module where the type is defined,
+      # not the module that triggered the registration
+      let ownerModule = if t.sym != nil: t.sym.itemId.module.int else: module
+      g.opsLog.add LogEntry(kind: HookEntry, op: op, module: ownerModule, key: key, sym: value)
       g.loadedOps[op][key] = value
-    g.attachedOps[op][t.itemId] = value
-    return
-  let existing = g.loadedOps[op].getOrDefault(key)
-  if existing == nil:
-    # Stamp the entry with the module whose compilation produced the hook
-    # (`module`), NOT the type's def module: each `nim m` is a separate
-    # process, so a hook lifted while compiling a *downstream* module simply
-    # does not exist in the def module's process — stamping it with the def
-    # module produced a `LogEntry` that no module ever writes (the def
-    # module's writer ran in another process that never lifted it; this
-    # module's writer skips it because `op.module != thisModule`) and codegen
-    # failed with "'=destroy' operator not found" (e.g. astdef's `TStrTable`,
-    # whose destroy is first needed by modulegraphs). This holds for nominal
-    # types as much as for generic/structural instances. Duplicate
-    # registrations across lifting modules are reconciled deterministically
-    # at load time (see the HookEntry replay in `replayStateChanges`).
-    g.opsLog.add LogEntry(kind: HookEntry, op: op, module: module, key: key, sym: value)
-    g.loadedOps[op][key] = value
-  elif existing != value:
-    # Re-registration replacing an earlier sym for the same key. This happens
-    # legitimately: `createTypeBoundOps` first registers empty `symPrototype`
-    # placeholders, then `produceSym` replaces them — in particular
-    # `produceSymDistinctType` replaces a distinct type's placeholder with the
-    # BASE type's hook (a `distinct string` uses string's `=sink`). The log
-    # must follow the replacement, otherwise the NIF ships the dead,
-    # empty-bodied prototype and codegen in another process calls a no-op
-    # `=sink`/`=copy`, silently losing the value (e.g. `conf.projectPath`
-    # ended up empty: "cannot open '/'").
-    g.loadedOps[op][key] = value
-    var updated = false
-    for e in mitems(g.opsLog):
-      if e.kind == HookEntry and e.op == op and e.key == key:
-        e.sym = value
-        e.module = module
-        updated = true
-        break
-    if not updated:
-      g.opsLog.add LogEntry(kind: HookEntry, op: op, module: module, key: key, sym: value)
-  g.attachedOps[op][t.itemId] = value
+  g.attachedOps[op][t.itemId] = LazySym(sym: value)
 
 proc setAttachedOp*(g: ModuleGraph; module: int; typeId: ItemId; op: TTypeAttachedOp; value: PSym) =
   ## Overload that takes ItemId directly, useful for registering hooks from NIF index.
-  g.attachedOps[op][typeId] = value
+  g.attachedOps[op][typeId] = LazySym(sym: value)
 
 proc setAttachedOpPartial*(g: ModuleGraph; module: int; t: PType; op: TTypeAttachedOp; value: PSym) =
   ## we also need to record this to the packed module.
-  g.attachedOps[op][t.itemId] = value
+  g.attachedOps[op][t.itemId] = LazySym(sym: value)
 
-proc completePartialOp*(g: ModuleGraph; module: int; t: PType; op: TTypeAttachedOp; value: PSym) {.inline.} =
-  discard
+proc completePartialOp*(g: ModuleGraph; module: int; t: PType; op: TTypeAttachedOp; value: PSym) =
+  if g.config.symbolFiles != disabledSf:
+    assert module < g.encoders.len
+    assert isActive(g.encoders[module])
+    toPackedGeneratedProcDef(value, g.encoders[module], g.packed[module].fromDisk)
+    #storeAttachedProcDef(t, op, value, g.encoders[module], g.packed[module].fromDisk)
 
 iterator getDispatchers*(g: ModuleGraph): PSym =
   for i in g.dispatchers.mitems:
-    yield i
+    yield resolveSym(g, i)
 
 proc addDispatchers*(g: ModuleGraph, value: PSym) =
   # TODO: add it for packed modules
-  g.dispatchers.add value
+  g.dispatchers.add LazySym(sym: value)
 
-iterator resolveLazySymSeq(g: ModuleGraph, list: var seq[PSym]): PSym =
+iterator resolveLazySymSeq(g: ModuleGraph, list: var seq[LazySym]): PSym =
   for it in list.mitems:
-    yield it
+    yield resolveSym(g, it)
 
-proc setMethodsPerType*(g: ModuleGraph; id: ItemId, methods: seq[PSym]) =
+proc setMethodsPerType*(g: ModuleGraph; id: ItemId, methods: seq[LazySym]) =
   # TODO: add it for packed modules
   g.methodsPerType[id] = methods
 
@@ -431,77 +428,29 @@ proc addNifReplayAction*(g: ModuleGraph; module: int32; n: PNode) =
 iterator getMethodsPerType*(g: ModuleGraph; t: PType): PSym =
   if g.methodsPerType.contains(t.itemId):
     for it in mitems g.methodsPerType[t.itemId]:
-      yield it
+      yield resolveSym(g, it)
 
 proc getToStringProc*(g: ModuleGraph; t: PType): PSym =
-  result = g.enumToStringProcs.getOrDefault(t.itemId)
-  if result == nil and g.config.cmd in {cmdNifC, cmdM}:
-    let key = typeKey(t, g.config, loadTypeCallback, loadSymCallback)
-    result = g.loadedEnumToStringProcs.getOrDefault(key)
+  result = resolveSym(g, g.enumToStringProcs[t.itemId])
   assert result != nil
 
 proc setToStringProc*(g: ModuleGraph; t: PType; value: PSym) =
-  g.enumToStringProcs[t.itemId] = value
+  g.enumToStringProcs[t.itemId] = LazySym(sym: value)
   let key = typeKey(t, g.config, loadTypeCallback, loadSymCallback)
-  # Stamp with the module that owns the generated proc, not the enum's def
-  # module: the def module's process may never have generated it (same
-  # "written by nobody" failure as hook entries, see setAttachedOp).
-  g.opsLog.add LogEntry(kind: EnumToStrEntry, module: value.itemId.module.int, key: key, sym: value)
+  let ownerModule = if t.sym != nil: t.sym.itemId.module.int else: value.itemId.module.int
+  g.opsLog.add LogEntry(kind: EnumToStrEntry, module: ownerModule, key: key, sym: value)
 
 iterator methodsForGeneric*(g: ModuleGraph; t: PType): (int, PSym) =
   if g.methodsPerGenericType.contains(t.itemId):
     for it in mitems g.methodsPerGenericType[t.itemId]:
-      yield (it[0], it[1])
+      yield (it[0], resolveSym(g, it[1]))
 
 proc addMethodToGeneric*(g: ModuleGraph; module: int; t: PType; col: int; m: PSym) =
-  g.methodsPerGenericType.mgetOrPut(t.itemId, @[]).add (col, m)
+  g.methodsPerGenericType.mgetOrPut(t.itemId, @[]).add (col, LazySym(sym: m))
   let key = typeKey(t, g.config, loadTypeCallback, loadSymCallback)
   let ownerModule = if t.sym != nil: t.sym.itemId.module.int else: module
   g.opsLog.add LogEntry(kind: MethodEntry, module: ownerModule, key: key, sym: m)
 
-proc logMethodDef*(g: ModuleGraph; s: PSym) =
-  ## Log a method registration (`cgmeth.methodDef`) so that importers and
-  ## the backend can rebuild the dispatch buckets (`g.methods`) from the
-  ## NIF replay log — the serialized method ast carries its dispatcher sym
-  ## at `dispatcherPos`, so replay reuses the original dispatcher that all
-  ## call sites reference by name (see `registerLoadedMethod`).
-  if g.config.cmd in {cmdNifC, cmdM}:
-    g.opsLog.add LogEntry(kind: MethodEntry, module: s.itemId.module.int,
-                          key: "", sym: s)
-
-proc registerLoadedMethod*(g: ModuleGraph; m: PSym) =
-  ## Rebuild the dispatch buckets from a serialized method registration.
-  ## Buckets group the methods sharing a dispatcher; the dispatcher's BODY
-  ## does not exist in serialized form — `generateIfMethodDispatchers`
-  ## synthesizes it in the backend from the complete bucket.
-  template dbg(msg: string) =
-    when defined(icDbgMeth):
-      echo "[icMeth] replay ", (if m != nil: m.name.s else: "nil"), ": ", msg
-  if m == nil or sfDispatcher in m.flags: dbg "skip self/nil"; return
-  if m.ast == nil or dispatcherPos >= m.ast.len:
-    dbg "no dispatcherPos (len " & $(if m.ast != nil: m.ast.len else: -1) & ")"
-    return
-  let dn = m.ast[dispatcherPos]
-  if dn == nil or dn.kind != nkSym or dn.sym == nil: dbg "empty dispatcher slot"; return
-  let disp = dn.sym
-  if sfDispatcher notin disp.flags: dbg "slot sym not a dispatcher"; return
-  dbg "ok -> bucket of " & disp.name.s & "." & $disp.disamb
-  for i in 0..<g.methods.len:
-    if g.methods[i].dispatcher.itemId == disp.itemId:
-      for existing in g.methods[i].methods:
-        if existing.itemId == m.itemId: return
-      g.methods[i].methods.add m
-      return
-  g.methods.add (methods: @[m], dispatcher: disp)
-
-proc flushMethodReplays*(g: ModuleGraph) =
-  ## Builds the dispatch buckets from the method registrations collected
-  ## during module loading; called once every module of the program is
-  ## loaded (`nifbackend.generateCode`).
-  for s in g.pendingMethodReplays:
-    registerLoadedMethod(g, s)
-  g.pendingMethodReplays.setLen 0
-
 proc logGenericInstance*(g: ModuleGraph; inst: PSym) =
   ## Log a generic instance so it gets written to the NIF file.
   ## This is needed when generic instances are created during compile-time
@@ -510,86 +459,6 @@ proc logGenericInstance*(g: ModuleGraph; inst: PSym) =
     let ownerModule = inst.itemId.module.int
     g.opsLog.add LogEntry(kind: GenericInstEntry, module: ownerModule, sym: inst)
 
-const
-  InstanceDisambBit* = 0x4000_0000'i32
-    ## Set in the `disamb` of routine instances whose value is content-derived
-    ## (see `setInstanceDisamb`); keeps them disjoint from the small counter
-    ## range ordinary symbols draw from, so the NIF name `name.disamb.module`
-    ## stays collision-free within a module.
-
-proc setInstanceDisamb*(g: ModuleGraph; inst, generic: PSym;
-                        concreteTypes: openArray[PType]) =
-  ## Under IC, replace a fresh routine instance's counter-based `disamb` with
-  ## a content-derived one: a hash of the generic's identity plus the
-  ## `typeKey` of every concrete type argument — exactly the identity the
-  ## instantiation cache compares. The instance's NIF name
-  ## `name.disamb.modsuffix` then differs only in the module suffix when the
-  ## same instantiation is made by different modules, which is the
-  ## prerequisite for cross-module generic-instance merging (and gives the
-  ## dce analysis its `offers` keys). The hash is computed once, here; it is
-  ## never recomputed — the value travels in the serialized `disamb` field.
-  if g.config.cmd notin {cmdNifC, cmdM}: return
-  if isDefined(g.config, "icNoInstKey"): return
-  var key = generic.name.s
-  key.add '.'
-  key.addInt generic.disamb
-  key.add '.'
-  key.add modname(generic.itemId.module, g.config)
-  for t in concreteTypes:
-    key.add '|'
-    key.add typeKey(t, g.config, loadTypeCallback, loadSymCallback)
-  let d = toMD5(key)
-  var h = (int32(d[0]) or (int32(d[1]) shl 8) or (int32(d[2]) shl 16) or
-           (int32(d[3] and 0x3F'u8) shl 24)) or InstanceDisambBit
-  # Same-name hash collisions inside this process get probed to the next
-  # free value; the loser stays correct (its name keeps the module suffix),
-  # it merely won't merge cross-module.
-  while true:
-    let probe = (inst.name.id, h)
-    if g.instDisambs.hasKey(probe):
-      if g.instDisambs[probe] == inst.itemId: break
-      h = if h == high(int32): InstanceDisambBit else: h + 1
-    else:
-      g.instDisambs[probe] = inst.itemId
-      break
-  inst.disamb = h
-
-const
-  HookDisambBit* = 0x2000_0000'i32
-    ## Set in the `disamb` of synthesized type-bound operators and `$enum`
-    ## procs whose value is content-derived (see `setHookDisamb`); disjoint
-    ## from both the small counter range and the `InstanceDisambBit` range.
-
-proc setHookDisamb*(g: ModuleGraph; hook: PSym; opName: string; typ: PType) =
-  ## Under IC, replace a synthesized hook's counter-based `disamb` with a
-  ## content-derived one: a hash of the operation name plus the `typeKey` of
-  ## the type it is bound to. Counter disambs renumber whenever an *earlier*
-  ## hook appears in a re-semmed module, so cached translation units keep
-  ## calling the old `_u<disamb>` C name while the regenerated producer
-  ## defines a new one — the hook flavor of the backend def-migration hole.
-  ## With a content-derived value the hook's NIF name (and hence its C name)
-  ## is stable as long as the type itself is unchanged.
-  if g.config.cmd notin {cmdNifC, cmdM}: return
-  if isDefined(g.config, "icNoHookKey"): return
-  var key = opName
-  key.add '|'
-  key.add typeKey(typ, g.config, loadTypeCallback, loadSymCallback)
-  let d = toMD5(key)
-  var h = (int32(d[0]) or (int32(d[1]) shl 8) or (int32(d[2]) shl 16) or
-           (int32(d[3] and 0x1F'u8) shl 24)) or HookDisambBit
-  # Same-name hash collisions inside this process get probed to the next
-  # free value (staying below InstanceDisambBit); the loser merely loses
-  # cross-run name stability.
-  while true:
-    let probe = (hook.name.id, h)
-    if g.instDisambs.hasKey(probe):
-      if g.instDisambs[probe] == hook.itemId: break
-      h = if h == InstanceDisambBit - 1'i32: HookDisambBit else: h + 1
-    else:
-      g.instDisambs[probe] = hook.itemId
-      break
-  hook.disamb = h
-
 proc hasDisabledAsgn*(g: ModuleGraph; t: PType): bool =
   let op = getAttachedOp(g, t, attachedAsgn)
   result = op != nil and sfError in op.flags
@@ -605,12 +474,11 @@ proc loadCompilerProc*(g: ModuleGraph; name: string): PSym =
   if g.config.symbolFiles == disabledSf and optWithinConfigSystem notin g.config.globalOptions:
     # For NIF-based compilation, search in loaded NIF modules
     when not defined(nimKochBootstrap):
-      # Try to resolve from NIF for both cmdNifC and cmdM (which uses NIF files)
-      if g.config.cmd in {cmdNifC, cmdM}:
+      # Only try to resolve from NIF if we're actually using NIF files (cmdNifC)
+      if g.config.cmd == cmdNifC:
         # First try system module (most compilerprocs are there)
         let systemFileIdx = g.config.m.systemFileIdx
-        if systemFileIdx != InvalidFileIdx and not g.withinSystem:
-          # Only try to load from NIF if the file exists (it may not during initial ic build)
+        if systemFileIdx != InvalidFileIdx:
           result = tryResolveCompilerProc(ast.program, name, systemFileIdx)
           if result != nil:
             strTableAdd(g.compilerprocs, result)
@@ -628,6 +496,20 @@ proc loadCompilerProc*(g: ModuleGraph; name: string): PSym =
               return result
     return nil
 
+  # slow, linear search, but the results are cached:
+  for module in 0..<len(g.packed):
+    #if isCachedModule(g, module):
+    let x = searchForCompilerproc(g.packed[module], name)
+    if x >= 0:
+      result = loadSymFromId(g.config, g.cache, g.packed, module, toPackedItemId(x))
+      if result != nil:
+        strTableAdd(g.compilerprocs, result)
+      return result
+
+proc loadPackedSym*(g: ModuleGraph; s: var LazySym) =
+  if s.sym == nil:
+    s.sym = loadSymFromId(g.config, g.cache, g.packed, s.id.module, s.id.packed)
+
 proc `$`*(u: SigHash): string =
   toBase64a(cast[cstring](unsafeAddr u), sizeof(u))
 
@@ -714,13 +596,16 @@ proc registerModule*(g: ModuleGraph; m: PSym) =
   if m.position >= g.ifaces.len:
     setLen(g.ifaces, m.position + 1)
 
+  if m.position >= g.packed.len:
+    setLen(g.packed.pm, m.position + 1)
+
   if g.ifaces[m.position].module == nil:
     g.ifaces[m.position] = Iface(module: m, converters: @[], patterns: @[],
                                 uniqueName: rope(uniqueModuleName(g.config, m)))
     initStrTables(g, m)
 
 proc registerModuleById*(g: ModuleGraph; m: FileIndex) =
-  registerModule(g, g.ifaces[int m].module)
+  registerModule(g, g.packed[int m].module)
 
 proc initOperators*(g: ModuleGraph): Operators =
   # These are safe for IC.
@@ -767,8 +652,6 @@ proc initModuleGraphFields(result: ModuleGraph) =
   result.operators = initOperators(result)
   result.emittedTypeInfo = initTable[string, FileIndex]()
   result.cachedFiles = newStringTable()
-  result.cachedMods = initIntSet()
-  result.hookClosure = initIntSet()
 
 proc newModuleGraph*(cache: IdentCache; config: ConfigRef): ModuleGraph =
   result = ModuleGraph()
@@ -791,22 +674,49 @@ proc resetAllModules*(g: ModuleGraph) =
   initModuleGraphFields(g)
 
 proc getModule*(g: ModuleGraph; fileIdx: FileIndex): PSym =
-  if fileIdx.int32 >= 0 and fileIdx.int32 < g.ifaces.len:
-    result = g.ifaces[fileIdx.int32].module
-  else:
-    result = nil
+  result = nil
+  if fileIdx.int32 >= 0:
+    if isCachedModule(g, fileIdx.int32):
+      result = g.packed[fileIdx.int32].module
+    elif fileIdx.int32 < g.ifaces.len:
+      result = g.ifaces[fileIdx.int32].module
 
 proc moduleOpenForCodegen*(g: ModuleGraph; m: FileIndex): bool {.inline.} =
-  result = true
+  if g.config.symbolFiles == disabledSf:
+    result = true
+  else:
+    result = g.packed[m.int32].status notin {undefined, stored, loaded}
 
-proc recordIcImplDep*(g: ModuleGraph; s: PSym) =
-  ## NeedsImpl edge tracking, see `icImplDeps`. Called from the compile-time
-  ## body consumption sites (vmgen's proc compilation, the getImpl opcodes).
-  ## Own-module and group-member entries are filtered out when the `.edges`
-  ## sidecar is written.
-  if g.config.cmd == cmdM and s != nil and s.kind in routineKinds and
-     s.itemId.module >= 0 and not isBackendMinted(s.itemId):
-    g.icImplDeps.incl module(s.itemId).int
+proc rememberEmittedTypeInfo*(g: ModuleGraph; m: FileIndex; ti: string) =
+  #assert(not isCachedModule(g, m.int32))
+  if g.config.symbolFiles != disabledSf:
+    #assert g.encoders[m.int32].isActive
+    assert g.packed[m.int32].status != stored
+    g.packed[m.int32].fromDisk.emittedTypeInfo.add ti
+    #echo "added typeinfo ", m.int32, " ", ti, " suspicious ", not g.encoders[m.int32].isActive
+
+proc rememberFlag*(g: ModuleGraph; m: PSym; flag: ModuleBackendFlag) =
+  if g.config.symbolFiles != disabledSf:
+    #assert g.encoders[m.int32].isActive
+    assert g.packed[m.position].status != stored
+    g.packed[m.position].fromDisk.backendFlags.incl flag
+
+proc closeRodFile*(g: ModuleGraph; m: PSym) =
+  if g.config.symbolFiles in {readOnlySf, v2Sf}:
+    # For stress testing we seek to reload the symbols from memory. This
+    # way much of the logic is tested but the test is reproducible as it does
+    # not depend on the hard disk contents!
+    let mint = m.position
+    saveRodFile(toRodFile(g.config, AbsoluteFile toFullPath(g.config, FileIndex(mint))),
+                g.encoders[mint], g.packed[mint].fromDisk)
+    g.packed[mint].status = stored
+
+  elif g.config.symbolFiles == stressTest:
+    # debug code, but maybe a good idea for production? Could reduce the compiler's
+    # memory consumption considerably at the cost of more loads from disk.
+    let mint = m.position
+    simulateCachedModule(g, m, g.packed[mint].fromDisk)
+    g.packed[mint].status = loaded
 
 proc dependsOn(a, b: int): int {.inline.} = (a shl 15) + b
 
@@ -890,108 +800,20 @@ proc needsCompilation*(g: ModuleGraph, fileIdx: FileIndex): bool =
 
 proc getBody*(g: ModuleGraph; s: PSym): PNode {.inline.} =
   result = s.ast[bodyPos]
+  if result == nil and g.config.symbolFiles in {readOnlySf, v2Sf, stressTest}:
+    result = loadProcBody(g.config, g.cache, g.packed, s)
+    s.ast[bodyPos] = result
   assert result != nil
 
+proc moduleFromRodFile*(g: ModuleGraph; fileIdx: FileIndex;
+                        cachedModules: var seq[FileIndex]): PSym =
+  ## Returns 'nil' if the module needs to be recompiled.
+  if g.config.symbolFiles in {readOnlySf, v2Sf, stressTest}:
+    result = moduleFromRodFile(g.packed, g.config, g.cache, fileIdx, cachedModules)
+  else:
+    result = nil
+
 when not defined(nimKochBootstrap):
-  proc registerLoadedHooks(g: ModuleGraph; logOps: seq[LogEntry]) =
-    let mainSuffix = getMainModuleSuffix(ast.program)
-    for x in logOps:
-      # A dependency's NIF may carry hooks whose syms belong to the module we
-      # are compiling fresh (e.g. a stale NIF of that very module written by an
-      # earlier in-process compilation). Loading those would collide with the
-      # freshly semchecked hook declarations.
-      if mainSuffix.len > 0 and
-         cachedModuleSuffix(g.config, x.sym.itemId.module.FileIndex) == mainSuffix:
-        continue
-      case x.kind
-      of HookEntry:
-        # The same structural hook may be serialized by several instantiating
-        # modules (a generic/structural instance has no single def site, so each
-        # using module owns its copy). Pick one deterministic program-wide winner
-        # by the smaller owning-module name, so every lookup resolves to the same
-        # sym regardless of module load order.
-        let existing = g.loadedOps[x.op].getOrDefault(x.key)
-        if existing == nil or
-           cachedModuleSuffix(g.config, x.sym.itemId.module.FileIndex) <
-           cachedModuleSuffix(g.config, existing.itemId.module.FileIndex):
-          g.loadedOps[x.op][x.key] = x.sym
-      of EnumToStrEntry:
-        g.loadedEnumToStringProcs[x.key] = x.sym
-      of MethodEntry:
-        # only `methodDef` registrations (empty key) rebuild dispatch
-        # buckets; the `addMethodToGeneric` flavor (typeKey key) announces
-        # the uninstantiated generic method, which must never enter a
-        # bucket (methodsPerGenericType replay is still a todo).
-        # Under `nim nifc` the replay is deferred: building a bucket forces
-        # the method's body, and a body loaded mid `loadModuleDependencies`
-        # registers modules it references in a different path context than
-        # the lazy loads during codegen do (`flushMethodReplays`).
-        if x.key.len == 0:
-          if g.config.cmd == cmdNifC:
-            g.pendingMethodReplays.add x.sym
-          else:
-            registerLoadedMethod(g, x.sym)
-      else:
-        discard
-
-  proc loadTransitiveHooks(g: ModuleGraph; deps: seq[ModuleSuffix]) =
-    ## Registers the serialized hooks (and enum-to-string procs) of every module
-    ## in the import closure of `deps`. Deliberately does NOT use
-    ## `moduleFromNifFile`: that would register the dep as a fully loaded module
-    ## and a later direct import of it would then skip `replayStateChanges`.
-    var stack = deps
-    var interf = initStrTable()
-    var interfHidden = initStrTable()
-    while stack.len > 0:
-      let suffix = stack.pop()
-      var isKnownFile = false
-      let fileIdx = g.config.registerNifSuffix(string suffix, isKnownFile)
-      if not g.hookClosure.containsOrIncl(fileIdx.int):
-        let precomp = loadNifModule(ast.program, suffix, interf, interfHidden, {})
-        registerLoadedHooks(g, precomp.logOps)
-        # Collect the dependency's macro-cache replay actions (put/inc/add/incl)
-        # so the importer being compiled also sees macrocache state registered
-        # by a transitively-imported module. Pragma replay actions are a backend
-        # concern and are intentionally not collected here.
-        for n in precomp.topLevel:
-          if n.kind == nkReplayAction and n.len >= 1 and n[0].kind == nkStrLit and
-             n[0].strVal in ["put", "inc", "add", "incl"]:
-            g.transitiveReplayActions.add n
-        for d in precomp.deps: stack.add d
-
-  proc materializeReexportedModule(g: ModuleGraph; mname, msuffix: string): PSym =
-    ## A re-exported MODULE (`import x; export x`) acts as a qualifier in the
-    ## re-exporting module's interface (`asmm.x86.nd`). Reconstruct a module
-    ## symbol for it and make its interface tables available for qualified
-    ## lookup (`someSym` reads `g.ifaces[position]`) — WITHOUT registering
-    ## the module: `Iface.module` stays nil so a later direct import still
-    ## takes the full load path (replayStateChanges etc.).
-    var isKnown = false
-    let fIdx = g.config.registerNifSuffix(msuffix, isKnown)
-    if fIdx.int >= g.ifaces.len: setLen(g.ifaces, fIdx.int + 1)
-    if g.ifaces[fIdx.int].module != nil and
-        g.ifaces[fIdx.int].module.name.s == mname:
-      # properly registered already (directly imported earlier): reuse it
-      return g.ifaces[fIdx.int].module
-    result = PSym(kindImpl: skModule, itemId: itemId(int32(fIdx), 0'i32),
-                  name: getIdent(g.cache, mname),
-                  infoImpl: newLineInfo(fIdx, 1, 1),
-                  positionImpl: int(fIdx))
-    setOwner(result, getPackage(g.config, g.cache, fIdx))
-    if g.ifaces[fIdx.int].module == nil and
-        not g.icQualIfaces.containsOrIncl(fIdx.int):
-      var interf = initStrTable()
-      var interfHidden = initStrTable()
-      let precomp = loadNifModule(ast.program, ModuleSuffix(msuffix),
-                                  interf, interfHidden, {})
-      # chains: the re-exported module may itself re-export modules
-      for (n2, s2) in precomp.reexportedModules:
-        let inner = materializeReexportedModule(g, n2, s2)
-        if inner != nil:
-          strTableAdd(interf, inner)
-      g.ifaces[fIdx.int].interf = interf
-      g.ifaces[fIdx.int].interfHidden = interfHidden
-
   proc moduleFromNifFile*(g: ModuleGraph; fileIdx: FileIndex;
                           flags: set[LoadFlag] = {}): PrecompiledModule =
     ## Returns 'nil' if the module needs to be recompiled.
@@ -1005,7 +827,7 @@ when not defined(nimKochBootstrap):
 
     let m = PSym(
       kindImpl: skModule,
-      itemId: itemId(int32(fileIdx), 0'i32),
+      itemId: ItemId(module: int32(fileIdx), item: 0'i32),
       name: getIdent(g.cache, splitFile(filename).name),
       infoImpl: newLineInfo(fileIdx, 1, 1),
       positionImpl: int(fileIdx))
@@ -1017,57 +839,27 @@ when not defined(nimKochBootstrap):
                            g.ifaces[fileIdx.int].interf,
                            g.ifaces[fileIdx.int].interfHidden, flags)
     result.module = m
-    for (mname, msuffix) in result.reexportedModules:
-      let ms = materializeReexportedModule(g, mname, msuffix)
-      if ms != nil:
-        strTableAdd(g.ifaces[fileIdx.int].interf, ms)
-
-    # Rebuild `procInstCache` from this module's generic-instance OFFERS so a
-    # consumer's `genericCacheGet` finds the instance and SKIPS re-running
-    # `instantiateBody` in its own module scope (which lacks symbols visible only
-    # at the generic's definition site — see ast2nif's `(offer …)`).
-    for off in result.genericOffers:
-      g.procInstCache.mgetOrPut(off.generic.itemId, @[]).add PInstantiation(
-        sym: off.inst, concreteTypes: off.concreteTypes,
-        genericParamsCount: off.genericParamsCount, compilesId: 0)
-
-    # Mark module as cached
-    g.cachedMods.incl fileIdx.int
-    g.hookClosure.incl fileIdx.int
 
     # Register hooks from NIF index with the module graph
-    registerLoadedHooks(g, result.logOps)
     for x in result.logOps:
       case x.kind
+      of HookEntry:
+        g.loadedOps[x.op][x.key] = x.sym
       of ConverterEntry:
-        g.ifaces[fileIdx.int].converters.add x.sym
-      of PureEnumEntry:
-        # rebuild the pure-enum list (source path: `addPureEnum`) so importers can
-        # offer this loaded `{.pure.}` enum's fields as the restricted pure-enum
-        # fallback (`importPureEnumFields`).
-        g.ifaces[fileIdx.int].pureEnums.add x.sym
+        g.ifaces[fileIdx.int].converters.add LazySym(sym: x.sym)
       of MethodEntry:
-        discard "dispatch buckets already rebuilt by registerLoadedHooks"
+        discard "todo"
+      of EnumToStrEntry:
+        discard "todo"
       of GenericInstEntry:
         raiseAssert "GenericInstEntry should not be in the NIF index"
-      of HookEntry, EnumToStrEntry:
-        discard "already done by registerLoadedHooks"
     # Register methods per type from NIF index
     discard "todo"
-    # `nim m` loads only its *direct* imports through this proc, but a hook for
-    # a structural type (e.g. `=destroy` for `seq[PNode]`) lives in the NIF of
-    # whichever module first lifted it — possibly a dependency of a dependency
-    # that the current module never imports directly. Walk the whole import
-    # closure so every serialized hook is visible. (Codegen, `nim nifc`, already
-    # walks the closure in nifbackend.loadModuleDependencies.)
-    if g.config.cmd == cmdM:
-      loadTransitiveHooks(g, result.deps)
 
 proc configComplete*(g: ModuleGraph) =
-  #rememberStartupConfig(g.startupPackedConfig, g.config)
-  discard
+  rememberStartupConfig(g.startupPackedConfig, g.config)
 
-proc onProcessing*(graph: ModuleGraph, fileIdx: FileIndex, moduleStatus: string, fromModule: PSym) =
+proc onProcessing*(graph: ModuleGraph, fileIdx: FileIndex, moduleStatus: string, fromModule: PSym, ) =
   let conf = graph.config
   let isNimscript = conf.isDefined("nimscript")
   if (not isNimscript) or hintProcessing in conf.cmdlineNotes:
@@ -1090,16 +882,7 @@ proc getPackage*(graph: ModuleGraph; fileIdx: FileIndex): PSym =
 
 proc belongsToStdlib*(graph: ModuleGraph, sym: PSym): bool =
   ## Check if symbol belongs to the 'stdlib' package.
-  # Compare the package *name* (an interned ident), not the package symbol's
-  # `.id`. Under per-module IC (`nim m`) the system module is loaded from a NIF
-  # in a process that does not compile it from source, so its package symbol is
-  # reconstructed with a fresh `.id` that no longer matches the freshly-interned
-  # package of a stdlib module compiled standalone here — making the old id
-  # comparison wrongly report `false` and inject `--import`ed modules into the
-  # stdlib. Both are canonically named `stdlib` (lib/stdlib.nimble); in a normal
-  # `nim c` build (system compiled from source) the ids match too, so this is a
-  # no-op there.
-  sym.getPackageSymbol.name.id == graph.systemModule.getPackageSymbol.name.id
+  sym.getPackageSymbol.getPackageId == graph.systemModule.getPackageId
 
 proc fileSymbols*(graph: ModuleGraph, fileIdx: FileIndex): SuggestFileSymbolDatabase =
   result = graph.suggestSymbols.getOrDefault(fileIdx, newSuggestFileSymbolDatabase(fileIdx, optIdeExceptionInlayHints in graph.config.globalOptions))

compiler/modulepaths.nim

@@ -109,11 +109,9 @@ proc mangleModuleName*(conf: ConfigRef; path: AbsoluteFile): string =
     of FromSearchPath: "@p"
     of FromNimblePath: "@n"
 
-  # Note: We encode ".." specially as "@d" to avoid issues with changeFileExt
-  # which would misinterpret ".." as "name.ext" and strip the second part.
   prefix & best.multiReplace(
-    {"..": "@d", $os.DirSep: "@s", $os.AltSep: "@s", "#": "@h", "@": "@@", ":": "@c"})
+    {$os.DirSep: "@s", $os.AltSep: "@s", "#": "@h", "@": "@@", ":": "@c"})
 
 proc demangleModuleName*(path: string): string =
   ## Demangle a relative module path.
-  result = path.multiReplace({"@@": "@", "@d": "..", "@h": "#", "@s": "/", "@m": "", "@p": "", "@n": "", "@c": ":"})
+  result = path.multiReplace({"@@": "@", "@h": "#", "@s": "/", "@m": "", "@p": "", "@n": "", "@c": ":"})

compiler/modules.nim

@@ -32,7 +32,7 @@ proc newModule*(graph: ModuleGraph; fileIdx: FileIndex): PSym =
   let filename = AbsoluteFile toFullPath(graph.config, fileIdx)
   # We cannot call ``newSym`` here, because we have to circumvent the ID
   # mechanism, which we do in order to assign each module a persistent ID.
-  result = PSym(kindImpl: skModule, itemId: itemId(int32(fileIdx), 0'i32),
+  result = PSym(kindImpl: skModule, itemId: ItemId(module: int32(fileIdx), item: 0'i32),
                 name: getModuleIdent(graph, filename),
                 infoImpl: newLineInfo(fileIdx, 1, 1))
   if not isNimIdentifier(result.name.s):

compiler/msgs.nim

@@ -125,25 +125,12 @@ proc fileInfoIdx*(conf: ConfigRef; filename: AbsoluteFile): FileIndex =
   var dummy: bool = false
   result = fileInfoIdx(conf, filename, dummy)
 
-proc expandOrPseudo(filename: string): AbsoluteFile =
-  # `expandFilename` raises OSError when the path does not exist on disk. That is
-  # fine for a real source path, but a macro can legitimately set a node's
-  # line-info file to a name that has no file behind it — e.g. the `???` sentinel
-  # produced by `toFilename` for a NIF-loaded node whose `fileIndex` is unknown
-  # (FileIndex(-1)). Falling back to the raw name lets the `AbsoluteFile` overload
-  # register it as a pseudo-path (like `command line`/`stdin`) instead of crashing
-  # the whole `nim m` child with an unhandled OSError.
-  try:
-    result = AbsoluteFile expandFilename(filename)
-  except OSError:
-    result = AbsoluteFile filename
-
 proc fileInfoIdx*(conf: ConfigRef; filename: RelativeFile; isKnownFile: var bool): FileIndex =
-  fileInfoIdx(conf, expandOrPseudo(filename.string), isKnownFile)
+  fileInfoIdx(conf, AbsoluteFile expandFilename(filename.string), isKnownFile)
 
 proc fileInfoIdx*(conf: ConfigRef; filename: RelativeFile): FileIndex =
   var dummy: bool = false
-  fileInfoIdx(conf, expandOrPseudo(filename.string), dummy)
+  fileInfoIdx(conf, AbsoluteFile expandFilename(filename.string), dummy)
 
 proc registerNifSuffix*(conf: ConfigRef; suffix: string; isKnownFile: var bool): FileIndex =
   result = conf.m.filenameToIndexTbl.getOrDefault(suffix, InvalidFileIdx)
@@ -253,7 +240,7 @@ proc setDirtyFile*(conf: ConfigRef; fileIdx: FileIndex; filename: AbsoluteFile)
 
 proc setHash*(conf: ConfigRef; fileIdx: FileIndex; hash: string) =
   assert fileIdx.int32 >= 0
-  when defined(gcArc) or defined(gcOrc) or defined(gcAtomicArc) or defined(gcYrc):
+  when defined(gcArc) or defined(gcOrc) or defined(gcAtomicArc):
     conf.m.fileInfos[fileIdx.int32].hash = hash
   else:
     shallowCopy(conf.m.fileInfos[fileIdx.int32].hash, hash)
@@ -261,7 +248,7 @@ proc setHash*(conf: ConfigRef; fileIdx: FileIndex; hash: string) =
 
 proc getHash*(conf: ConfigRef; fileIdx: FileIndex): string =
   assert fileIdx.int32 >= 0
-  when defined(gcArc) or defined(gcOrc) or defined(gcAtomicArc) or defined(gcYrc):
+  when defined(gcArc) or defined(gcOrc) or defined(gcAtomicArc):
     result = conf.m.fileInfos[fileIdx.int32].hash
   else:
     shallowCopy(result, conf.m.fileInfos[fileIdx.int32].hash)
@@ -524,9 +511,6 @@ proc sourceLine*(conf: ConfigRef; i: TLineInfo): string =
   ## 1-based index (matches editor line numbers); 1st line is for i.line = 1
   ## last valid line is `numLines` inclusive
   if i.fileIndex.int32 < 0: return ""
-  # line 0 means "unknown": nodes synthesized from an IC-loaded template or
-  # macro body carry no source position.
-  if i.line.int < 1: return ""
   let num = numLines(conf, i.fileIndex)
   # can happen if the error points to EOF:
   if i.line.int > num: return ""
@@ -680,9 +664,7 @@ template internalAssert*(conf: ConfigRef, e: bool) =
 
 template lintReport*(conf: ConfigRef; info: TLineInfo, beau, got: string, extraMsg = "") =
   let m = "'$1' should be: '$2'$3" % [got, beau, extraMsg]
-  let msg = if optStyleError in conf.globalOptions: errGenerated
-            elif optStyleWarning in conf.globalOptions: warnUser
-            else: hintName
+  let msg = if optStyleError in conf.globalOptions: errGenerated else: hintName
   liMessage(conf, info, msg, m, doNothing, instLoc())
 
 proc quotedFilename*(conf: ConfigRef; fi: FileIndex): Rope =

compiler/nifbackend.nim

@@ -17,39 +17,18 @@
 ##   1. Compile modules to NIF: nim m mymodule.nim
 ##   2. Generate C from NIF: nim nifc myproject.nim
 
-import std/[intsets, tables, sets, os, algorithm, syncio, times, strutils]
+import std/[intsets, tables, sets, os]
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
 
 import ast, options, lineinfos, modulegraphs, cgendata, cgen,
-  pathutils, extccomp, msgs, modulepaths, idents, types, ast2nif, typekeys,
-  cnif
-from cgmeth import generateIfMethodDispatchers
-import ic / replayer
+  pathutils, extccomp, msgs, modulepaths, idents, types, ast2nif
 
-proc loadModuleDependencies(g: ModuleGraph; mainFileIdx: FileIndex;
-                            nifFiles: var seq[string];
-                            depFlags: set[LoadFlag] = {LoadFullAst}): seq[PrecompiledModule] =
+proc loadModuleDependencies(g: ModuleGraph; mainFileIdx: FileIndex): seq[PrecompiledModule] =
   ## Traverse the module dependency graph using a stack.
   ## Returns all modules that need code generation, in dependency order.
-  ##
-  ## The main module is always loaded with its full AST (it is the codegen
-  ## target). `depFlags` governs the rest: the whole-program backend needs every
-  ## module's full AST (it generates code for all of them), but a per-module
-  ## stage codegens only one target, so it loads the others interface-only
-  ## (`depFlags = {}`) — the interface, hooks, methods and the `(replay ...)`
-  ## directives are loaded regardless of `LoadFullAst`, and demanded bodies are
-  ## fetched lazily from the kept-open stream, so the per-module proc-body ASTs
-  ## (the bulk of the memory) are never materialized for non-targets.
-  # The main module is loaded by its SOURCE FileIndex, but its serialized
-  # symbols carry the module's NIF suffix. Pre-alias the suffix to the source
-  # index so that `registerNifSuffix` does not allocate a second FileIndex for
-  # the same module, which would split its codegen across two C translation
-  # units (top-level globals in one, procs in the other → undeclared symbols).
-  g.config.m.filenameToIndexTbl[cachedModuleSuffix(g.config, mainFileIdx)] = mainFileIdx
   let mainModule = moduleFromNifFile(g, mainFileIdx, {LoadFullAst})
-  nifFiles.add toNifFilename(g.config, mainFileIdx)
 
   var stack: seq[ModuleSuffix] = @[]
   result = @[]
@@ -65,17 +44,14 @@ proc loadModuleDependencies(g: ModuleGraph; mainFileIdx: FileIndex;
     let suffix = stack.pop()
 
     if not visited.containsOrIncl(suffix.string):
-      var isKnownFile = false
-      let fileIdx = g.config.registerNifSuffix(suffix.string, isKnownFile)
-      let precomp = moduleFromNifFile(g, fileIdx, depFlags)
+      let nifFile = toGeneratedFile(g.config, AbsoluteFile(suffix.string), ".nif")
+      let fileIdx = msgs.fileInfoIdx(g.config, nifFile)
+      let precomp = moduleFromNifFile(g, fileIdx, {LoadFullAst})
       if precomp.module != nil:
         result.add precomp
-        nifFiles.add toNifFilename(g.config, fileIdx)
         for dep in precomp.deps:
           if not visited.contains(dep.string):
             stack.add dep
-      else:
-        assert false, "Recompiling module is not implemented."
 
   if mainModule.module != nil:
     result.add mainModule
@@ -84,13 +60,7 @@ proc setupNifBackendModule(g: ModuleGraph; module: PSym): BModule =
   ## Set up a BModule for code generation from a NIF module.
   if g.backend == nil:
     g.backend = cgendata.newModuleList(g)
-  result = cgen.newModule(BModuleList(g.backend), module, g.config, idGeneratorForBackend(module))
-
-proc isMetaIter(t: PType, closure: RootRef): bool =
-  # openArray/varargs hooks are sem bookkeeping: no real flow ever demands
-  # them, and generating one pollutes the TU's type cache with a struct
-  # descriptor for what must remain a (ptr, len) parameter expansion
-  t.kind in tyMetaTypes + {tyTyped, tyUntyped, tyNone, tyVarargs, tyOpenArray}
+  result = cgen.newModule(BModuleList(g.backend), module, g.config, idGeneratorFromModule(module))
 
 proc finishModule(g: ModuleGraph; bmod: BModule) =
   # Finalize the module (this adds it to modulesClosed)
@@ -98,52 +68,9 @@ proc finishModule(g: ModuleGraph; bmod: BModule) =
   let initStmt = newNode(nkStmtList)
   finalCodegenActions(g, bmod, initStmt)
 
-  # NB: the method dispatchers are emitted in `emitMethodDispatchers`,
-  # between the module loop and this finish loop: their bodies demand the
-  # method definitions, which can in turn demand definitions from modules
-  # the backend never loaded — and a TU demand-created during the LAST
-  # finishModule call would miss `modulesClosed` and never be written.
-
-proc emitMethodDispatchers(g: ModuleGraph) =
-  ## Synthesizes the method dispatcher bodies from the replayed dispatch
-  ## buckets (`registerLoadedMethod`) and emits their definitions into the
-  ## main TU. Main is regenerated on every run, so a dispatcher — whose
-  ## body enumerates the whole program's method set — can never go stale
-  ## inside a cached TU; cross-TU callers prototype it (see genProcLvl3).
-  let bl = BModuleList(g.backend)
-  var mainMod: BModule = nil
-  for m in bl.mods:
-    if m != nil and m.module != nil and sfMainModule in m.module.flags:
-      mainMod = m
-      break
-  if mainMod == nil: return
-  generateIfMethodDispatchers(g, mainMod.idgen)
+  # Generate dispatcher methods
   for disp in getDispatchers(g):
-    if not containsOrIncl(mainMod.declaredThings, disp.id):
-      genProcLvl3(mainMod, disp)
-
-proc signatureHasMetaType(t: PType; depth: int = 0): bool =
-  ## Whether a routine signature mentions a compile-time/meta element type
-  ## (`typed`/`untyped` — e.g. `echo`'s `varargs[typed]` — typedesc, static,
-  ## generic param). Such routines are expanded at their call sites and never
-  ## emitted standalone, so the per-module owned-routine seeding must skip them
-  ## (`getTypeDescAux(tyTyped)` otherwise). `tfHasMeta` alone misses the varargs
-  ## element case, hence the explicit scan.
-  result = false
-  if t == nil or depth > 8: return false
-  if t.kind == tyGenericBody:
-    # The uninstantiated template carried as a `tyGenericInst`'s first child
-    # always mentions its `tyGenericParam` placeholders, but the instance
-    # itself is fully concrete (e.g. `var CountTable[SigHash]`). Descending
-    # here would wrongly flag every routine with a generic-instance parameter
-    # as meta and drop it from the owned-routine seeding -> undefined symbols
-    # at link (its only definer never emits it).
-    return false
-  if t.kind in {tyTyped, tyUntyped, tyTypeDesc, tyStatic, tyGenericParam,
-                tyAnything, tyFromExpr, tyError}:
-    return true
-  for k in t.kids:
-    if signatureHasMetaType(k, depth + 1): return true
+    genProcLvl3(bmod, disp)
 
 proc generateCodeForModule(g: ModuleGraph; precomp: PrecompiledModule) =
   ## Generate C code for a single module.
@@ -152,366 +79,76 @@ proc generateCodeForModule(g: ModuleGraph; precomp: PrecompiledModule) =
   if bmod == nil:
     bmod = setupNifBackendModule(g, precomp.module)
 
-  # Apply the module's recorded C compile/link directives (passl/passc/...)
-  # before generating code: the link step needs them (e.g. math's -lm).
-  replayBackendActions(g, precomp.module, precomp.topLevel)
-
   # Generate code for the module's top-level statements
   if precomp.topLevel != nil:
     cgen.genTopLevelStmt(bmod, precomp.topLevel)
 
-  # Per-module backend: emit the bodies of the routines this module OWNS, not
-  # only the ones its top-level happens to demand. Procs are serialized as lazy
-  # `(sd ...)` defs (never as `nkProcDef` statements), so `genTopLevelStmt` never
-  # reaches them; a routine called only from *other* modules would otherwise be
-  # emitted by nobody, because every module now merely prototypes its foreign
-  # callees instead of funnelling their bodies (see `cgen.emitsBodyInThisModule`).
-  # The merge stage's DCE drops whatever turns out globally dead.
-  if g.config.cmd == cmdNifC and g.config.icBackendStage == "cg":
-    let modPos = precomp.module.position
-    for s in moduleSymbolStubs(ast.program, FileIndex modPos):
-      if s.itemId.module == modPos and
-         s.kind in {skProc, skFunc, skConverter, skMethod} and
-         # Only MODULE-level routines: a nested/closure proc (its owner is a
-         # proc) captures its enclosing scope and cannot be emitted standalone —
-         # the captured params have no loc → `expr: param not init`. Nested procs
-         # are emitted via their enclosing routine's lambda-lifting, so seeding
-         # the enclosing (module-level) routine already covers them.
-         s.skipGenericOwner != nil and s.skipGenericOwner.kind == skModule and
-         s.magic == mNone and
-         # Skip generic instances: they have no single owning-module top-level
-         # and are emitted by demand (emit-everywhere, deduped by the merge
-         # stage). An instance has an empty `genericParamsPos` just like a plain
-         # concrete proc, so only `sfFromGeneric` tells them apart; seeding one
-         # would force standalone codegen of an instance body whose `when T is X`
-         # branches were never folded for this path → `genMagicExpr: mIs`.
-         sfFromGeneric notin s.flags and
-         # Every other routine the module owns must be emitted here, exported or
-         # not: a non-exported helper is still reached from another module when a
-         # `template`/inline routine expands at a call site there (e.g. msgs'
-         # `internalErrorImpl` behind the `internalError` template), and that
-         # caller now only prototypes it. `{.error.}`/`compileTime` sentinels and
-         # bodyless forward decls are not real codegen targets.
-         {sfForward, sfImportc, sfCompileTime, sfError} * s.flags == {} and
-         s.typ != nil and not signatureHasMetaType(s.typ) and
-         s.ast != nil and s.ast.safeLen > bodyPos and
-         s.ast[genericParamsPos].kind == nkEmpty and
-         s.ast[bodyPos].kind != nkEmpty:
-        # a concrete, non-generic, runtime routine with a real body, owned here
-        requestProcDef(bmod, s)
+proc generateCode*(g: ModuleGraph; mainFileIdx: FileIndex) =
+  ## Main entry point for NIF-based C code generation.
+  ## Traverses the module dependency graph and generates C code.
 
-proc loadBackendModules(g: ModuleGraph; mainFileIdx: FileIndex):
-    tuple[modules: seq[PrecompiledModule], precompSys: PrecompiledModule,
-          nifFiles: seq[string]] =
-  ## Shared by the per-module `cg` and `emit` stages: load system + the main
-  ## module's whole import closure and set up a `BModule` for each, so every
-  ## type/symbol resolves and `getCFile` yields the same path both stages use.
-  ## The main module is loaded by its source index (its NIF suffix is aliased to
-  ## it in `loadModuleDependencies`), so it gets exactly one `BModule`.
-  ##
-  ## Only the main module — the codegen target of the stages that use this — is
-  ## loaded with its full AST; every other module is loaded interface-only so
-  ## the whole program's proc bodies are not materialized into this process (that
-  ## was ~1.8 GB for the compiler's main `cg`). The `link` stage codegens nothing
-  ## and only needs each module's `(replay ...)` directives, which load anyway.
+  # Reset backend state
   resetForBackend(g)
+
   var isKnownFile = false
   let systemFileIdx = registerNifSuffix(g.config, "sysma2dyk", isKnownFile)
   g.config.m.systemFileIdx = systemFileIdx
-  var precompSys = moduleFromNifFile(g, systemFileIdx, {AlwaysLoadInterface})
-  g.systemModule = precompSys.module
-  var nifFiles: seq[string] = @[toNifFilename(g.config, systemFileIdx)]
-  var modules = loadModuleDependencies(g, mainFileIdx, nifFiles, depFlags = {})
-  # loadModuleDependencies traverses the project's import closure and stops at
-  # system. The whole-program backend then demand-loads system's own closure
-  # (locks, allocators, threads, …) during codegen; the per-module backend
-  # instead makes every one of those a first-class cg/emit target, so load that
-  # closure here too — otherwise `findTargetModule` cannot resolve their suffix.
-  block:
-    var visited = initHashSet[string]()
-    visited.incl "sysma2dyk"
-    for m in modules:
-      visited.incl cachedModuleSuffix(g.config, FileIndex m.module.position)
-    var stack: seq[ModuleSuffix] = @[]
-    if precompSys.module != nil:
-      for dep in precompSys.deps: stack.add dep
-    while stack.len > 0:
-      let suffix = stack.pop()
-      if not visited.containsOrIncl(suffix.string):
-        var isKnown = false
-        let fileIdx = registerNifSuffix(g.config, suffix.string, isKnown)
-        let precomp = moduleFromNifFile(g, fileIdx, {})
-        if precomp.module != nil:
-          modules.add precomp
-          nifFiles.add toNifFilename(g.config, fileIdx)
-          for dep in precomp.deps: stack.add dep
-  flushMethodReplays(g)
-  for m in modules:
-    discard setupNifBackendModule(g, m.module)
-  if precompSys.module != nil:
-    discard setupNifBackendModule(g, precompSys.module)
-  result = (modules, precompSys, nifFiles)
+  #msgs.fileInfoIdx(g.config,
+  #    g.config.libpath / RelativeFile"system.nim")
 
-proc loadDepClosure(g: ModuleGraph; targetSuffix: string):
-    tuple[modules: seq[PrecompiledModule], precompSys: PrecompiledModule,
-          target: PrecompiledModule] =
-  ## Per-module `cg`/`emit` for a NON-main target: load system + the target
-  ## module + the target's transitive import closure ONLY — not the whole
-  ## program. This is the "process the one file it is passed" model (à la
-  ## Nimony's `hexer c file.nif`): the foreign symbols the target's codegen
-  ## demands are loaded lazily by `ast2nif.moduleId`, which opens any referenced
-  ## module's NIF index on first touch, so a body in a not-loaded module still
-  ## resolves. The closure is loaded as full `BModule`s only so that the
-  ## incidental `g.mods[pos]` accesses during codegen resolve; system's own
-  ## internal closure (allocators, locks, …) is included because a target's
-  ## emit-everywhere codegen can demand those without importing them directly.
-  ##
-  ## The whole program is no longer loaded in this process, which is what bounds
-  ## per-process memory under nifmake's parallel fan-out (the main module's `cg`,
-  ## which still loads everything for NimMain's init list and the method
-  ## dispatchers, runs essentially alone since every other `.c.nif` precedes it).
-  resetForBackend(g)
-  var isKnownFile = false
-  let systemFileIdx = registerNifSuffix(g.config, "sysma2dyk", isKnownFile)
-  g.config.m.systemFileIdx = systemFileIdx
-  let precompSys = moduleFromNifFile(g, systemFileIdx, {AlwaysLoadInterface})
+  # Load system module first - it's always needed and contains essential hooks
+  var precompSys = PrecompiledModule(module: nil)
+  precompSys = moduleFromNifFile(g, systemFileIdx, {LoadFullAst, AlwaysLoadInterface})
   g.systemModule = precompSys.module
 
-  var modules: seq[PrecompiledModule] = @[]
-  var visited = initHashSet[string]()
-  visited.incl "sysma2dyk"
-
-  # Only the target is codegen'd, so only it needs its full AST; the closure is
-  # loaded interface-only (demanded bodies come lazily from the kept-open
-  # streams), which is what keeps a per-module process light under parallel fan-out.
-  var isKnown = false
-  let targetIdx = registerNifSuffix(g.config, targetSuffix, isKnown)
-  let target = moduleFromNifFile(g, targetIdx, {LoadFullAst})
-  visited.incl targetSuffix
-
-  var stack: seq[ModuleSuffix] = @[]
-  if target.module != nil:
-    modules.add target
-    for dep in target.deps: stack.add dep
-  if precompSys.module != nil:
-    for dep in precompSys.deps: stack.add dep
-  while stack.len > 0:
-    let suffix = stack.pop()
-    if not visited.containsOrIncl(suffix.string):
-      var isKnown2 = false
-      let fileIdx = registerNifSuffix(g.config, suffix.string, isKnown2)
-      let precomp = moduleFromNifFile(g, fileIdx, {})
-      if precomp.module != nil:
-        modules.add precomp
-        for dep in precomp.deps: stack.add dep
-  flushMethodReplays(g)
-  for m in modules:
-    discard setupNifBackendModule(g, m.module)
-  if precompSys.module != nil:
-    discard setupNifBackendModule(g, precompSys.module)
-  result = (modules, precompSys, target)
-
-proc findTargetModule(g: ModuleGraph; modules: seq[PrecompiledModule];
-                      precompSys: PrecompiledModule; suffix: string): PrecompiledModule =
-  ## The loaded module whose NIF suffix is `suffix` (the `--icBackendModule`
-  ## value), or a nil module if none matches.
-  result = PrecompiledModule(module: nil)
-  for m in modules:
-    if cachedModuleSuffix(g.config, FileIndex m.module.position) == suffix:
-      return m
-  if precompSys.module != nil and
-      cachedModuleSuffix(g.config, FileIndex precompSys.module.position) == suffix:
-    return precompSys
-
-proc generateCgStage(g: ModuleGraph; mainFileIdx: FileIndex) =
-  ## Per-module backend codegen (`--icBackendStage:cg --icBackendModule:<suffix>`):
-  ## generate C for the single module named by `icBackendModule` and write only
-  ## its `.c.nif` artifact (no merge, no `.c` render, no cc/link — those are
-  ## separate nifmake rules).
-  ##
-  ## `findPendingModule` routes every demand into the target (emit-everywhere).
-  ##
-  ## A NON-main target loads only its own import closure (`loadDepClosure`); the
-  ## whole program is no longer pulled into every parallel `cg` process. The main
-  ## module still loads everything (`loadBackendModules`) because NimMain's init
-  ## list and the method dispatchers are whole-program; its `cg` runs essentially
-  ## alone (every other `.c.nif` precedes it), so it does not contend for memory.
-  let mainSuffix = cachedModuleSuffix(g.config, mainFileIdx)
-  let targetIsMain = g.config.icBackendModule.len == 0 or
-                     g.config.icBackendModule == mainSuffix
-  var modules: seq[PrecompiledModule]
-  var precompSys: PrecompiledModule
-  var target: PrecompiledModule
-  if targetIsMain:
-    var nifFiles: seq[string]
-    (modules, precompSys, nifFiles) = loadBackendModules(g, mainFileIdx)
-    if modules.len == 0:
-      rawMessage(g.config, errGenerated,
-        "Cannot load NIF file for main module: " & toFullPath(g.config, mainFileIdx))
-      return
-    # No whole-program DCE here: each module emits the routines it owns and the
-    # MERGE stage recomputes the one program-wide live set across all `.c.nif`s.
-    # Running a whole-program liveness pass over all ~260 NIFs in the main `cg`
-    # would cost ~900 MB for a result the merge stage throws away.
-    target = findTargetModule(g, modules, precompSys, g.config.icBackendModule)
-  else:
-    # No whole-program load, hence no whole-program DCE: the target emits its
-    # full demanded closure and the merge stage drops what is globally dead.
-    (modules, precompSys, target) = loadDepClosure(g, g.config.icBackendModule)
-  if target.module == nil:
-    rawMessage(g.config, errGenerated,
-      "per-module codegen: module not found for suffix: " & g.config.icBackendModule)
-    return
-
-  generateCodeForModule(g, target)
-  let bl = BModuleList(g.backend)
-  # The main module also owns the whole-program method dispatchers + NimMain.
-  if sfMainModule in target.module.flags:
-    emitMethodDispatchers(g)
-    # NimMain (generated when the main module is finished) must call every other
-    # module's init/datInit. Those translation units are produced by their own
-    # `cg` processes, so the calls are registered here from each `.c.nif` meta
-    # head — which is why the main module's `cg` runs last, after every other
-    # `.c.nif` exists. Modules without init code (no `.c.nif`) register nothing.
-    for m in bl.mods:
-      if m != nil and sfMainModule notin m.module.flags:
-        let heads = readCnifHeads(getCFile(m).string & ".nif")
-        registerReusedModuleToMain(bl, m, heads.initRequired, heads.datInitRequired)
-  let tb = bl.mods[target.module.position]
-  if tb != nil:
-    finishModule(g, tb)
-
-  # Writes only the target's `.c.nif` (every other loaded module's TU is empty,
-  # so `cgenWriteModules` emits no artifact for it). cc/link are NOT run here.
-  cgenWriteModules(g.backend, g.config)
-
-  # Always leave a `.c.nif` for the target, even when the module has no code
-  # (a leaf library whose procs all emit into their users): the per-module
-  # nifmake graph declares one `.c.nif` output per `cg` rule, so a missing one
-  # would re-fire the rule forever. An empty artifact renders to an empty `.c`.
-  if tb != nil:
-    let artifact = getCFile(tb).string & ".nif"
-    if not fileExists(artifact):
-      writeCnifArtifact("", artifact,
-        semmedNif = toNifFilename(g.config, FileIndex target.module.position),
-        moduleBase = $getSomeNameForModule(tb))
-
-proc generateMergeStage(g: ModuleGraph) =
-  ## Per-module backend merge (`--icBackendStage:merge`): a pure artifact
-  ## operation, no module graph loaded. Reads every `.c.nif` the `cg` stages
-  ## wrote, computes the global live set and — for each `'u'`-flagged unique
-  ## definition that several `cg` processes emitted (emit-everywhere) — the one
-  ## artifact allowed to embed its body, and writes the decision the `emit`
-  ## stages consume — the cross-process replacement for what used to be
-  ## in-process first-claimant/DCE coordination.
-  let nimcache = getNimcacheDir(g.config).string
-  var files: seq[string] = @[]
-  for artifact in walkFiles(nimcache / "*.c.nif"):
-    files.add artifact
-  sort files
-  let decision = computeMergeDecision(files)
-  if decision.broken:
-    rawMessage(g.config, errGenerated,
-      "per-module backend merge: a .c.nif artifact is missing or unparsable")
-    return
-  writeMergeDecision(nimcache / MergeDecisionFile, decision)
-  if isDefined(g.config, "icDceCheck"):
-    stderr.writeLine "[icMerge] artifacts: " & $files.len &
-      " live: " & $decision.live.len & " defs: " & $decision.defs &
-      " liveDefs: " & $decision.liveDefs & " owned: " & $decision.owners.len
-
-proc generateEmitStage(g: ModuleGraph; mainFileIdx: FileIndex) =
-  ## Per-module backend emit (`--icBackendStage:emit --icBackendModule:<suffix>`):
-  ## render the target module's final `.c` from its `.c.nif` and the merge
-  ## decision. Loads the target the same way `cg` does so `getCFile` returns the
-  ## identical path `cg` wrote to (the main module's source-vs-suffix aliasing in
-  ## particular); no codegen runs. A non-main target loads only its own closure
-  ## (`loadDepClosure`) so emit, like `cg`, stays bounded under parallel fan-out.
-  let mainSuffix = cachedModuleSuffix(g.config, mainFileIdx)
-  let targetIsMain = g.config.icBackendModule.len == 0 or
-                     g.config.icBackendModule == mainSuffix
-  var modules: seq[PrecompiledModule]
-  var precompSys: PrecompiledModule
-  var target: PrecompiledModule
-  if targetIsMain:
-    var nifFiles: seq[string]
-    (modules, precompSys, nifFiles) = loadBackendModules(g, mainFileIdx)
-    if modules.len == 0:
-      rawMessage(g.config, errGenerated,
-        "Cannot load NIF file for main module: " & toFullPath(g.config, mainFileIdx))
-      return
-    target = findTargetModule(g, modules, precompSys, g.config.icBackendModule)
-  else:
-    (modules, precompSys, target) = loadDepClosure(g, g.config.icBackendModule)
-  if target.module == nil:
-    rawMessage(g.config, errGenerated,
-      "per-module emit: module not found for suffix: " & g.config.icBackendModule)
-    return
-  let decision = readMergeDecision(getNimcacheDir(g.config).string / MergeDecisionFile)
-  if decision.broken:
-    rawMessage(g.config, errGenerated,
-      "per-module emit: missing or unparsable merge decision " & MergeDecisionFile)
-    return
-  let bmod = BModuleList(g.backend).mods[target.module.position]
-  let cfile = getCFile(bmod).string
-  let artifact = cfile & ".nif"
-  var dropped = 0
-  let code = renderCFromArtifact(artifact, decision, extractFilename(artifact), dropped)
-  writeFile(cfile, code)
-  if isDefined(g.config, "icDceCheck"):
-    stderr.writeLine "[icEmit] " & extractFilename(cfile) & " dropped " &
-      $dropped & " bodies (" & $code.len & " bytes)"
-
-proc generateLinkStage(g: ModuleGraph; mainFileIdx: FileIndex) =
-  ## Per-module backend link (`--icBackendStage:link`): the `emit` stages have
-  ## written every module's `.c`; register them and run the C compiler + linker
-  ## once via `extccomp.callCCompiler` (which parallelizes the per-file cc and
-  ## skips up-to-date objects itself). No codegen runs — the graph is loaded only
-  ## so `getCFile` yields each module's emitted `.c` path.
-  let (modules, precompSys, _) = loadBackendModules(g, mainFileIdx)
+  # Load all modules in dependency order using stack traversal
+  # This must happen BEFORE any code generation so that hooks are loaded into loadedOps
+  let modules = loadModuleDependencies(g, mainFileIdx)
   if modules.len == 0:
     rawMessage(g.config, errGenerated,
       "Cannot load NIF file for main module: " & toFullPath(g.config, mainFileIdx))
     return
-  # The per-module `cg` processes each collect their module's C compile/link
-  # directives (`{.passL: "-lm".}` etc.) via `replayBackendActions`, but those
-  # live in the cg process and never reach this separate link process. Re-collect
-  # every loaded module's directives here so the final `callCCompiler` sees them
-  # (without this, math's `-lm` is lost → undefined `floor`/`pow`/… at link).
+
+  # Set up backend modules for all modules that need code generation
   for m in modules:
-    replayBackendActions(g, m.module, m.topLevel)
+    discard setupNifBackendModule(g, m.module)
+
+  # Also ensure system module is set up and generated first if it exists
   if precompSys.module != nil:
-    replayBackendActions(g, precompSys.module, precompSys.topLevel)
-  let bl = BModuleList(g.backend)
-  for m in bl.mods:
+    discard setupNifBackendModule(g, precompSys.module)
+    generateCodeForModule(g, precompSys)
+
+  # Track which modules have been processed to avoid duplicates
+  var processed = initIntSet()
+  if precompSys.module != nil:
+    processed.incl precompSys.module.position
+
+  # Generate code for all modules (skip system since it's already processed)
+  for m in modules:
+    if not processed.containsOrIncl(m.module.position):
+      generateCodeForModule(g, m)
+
+  # during code generation of `main.nim` we can trigger the code generation
+  # of symbols in different modules so we need to finish these modules
+  # here later, after the above loop!
+  # Important: The main module must be finished LAST so that all other modules
+  # have registered their init procs before genMainProc uses them.
+  var mainModule: BModule = nil
+  for m in BModuleList(g.backend).mods:
     if m != nil:
-      let cfile = getCFile(m)
-      # Only modules that are their own cg/emit target produced a `.c`; the rest
-      # (extra members of system's closure that no build rule targets) had their
-      # code emit-everywhere'd into the targets, so they have no file to compile.
-      if not fileExists(cfile.string): continue
-      var cf = Cfile(nimname: m.module.name.s, cname: cfile,
-                     obj: completeCfilePath(g.config, toObjFile(g.config, cfile)),
-                     flags: {})
-      addFileToCompile(g.config, cf)
+      assert m.module != nil
+      if sfMainModule in m.module.flags:
+        mainModule = m
+      else:
+        finishModule g, m
+  if mainModule != nil:
+    finishModule g, mainModule
+
+  # Write C files
+  cgenWriteModules(g.backend, g.config)
+
+  # Run C compiler
   if g.config.cmd != cmdTcc:
     extccomp.callCCompiler(g.config)
-
-proc generateCode*(g: ModuleGraph; mainFileIdx: FileIndex) =
-  ## Main entry point for NIF-based C code generation.
-  ## Traverses the module dependency graph and generates C code.
-  if g.config.icBackendStage == "cg":
-    generateCgStage(g, mainFileIdx)
-    return
-  elif g.config.icBackendStage == "merge":
-    generateMergeStage(g)
-    return
-  elif g.config.icBackendStage == "emit":
-    generateEmitStage(g, mainFileIdx)
-    return
-  elif g.config.icBackendStage == "link":
-    generateLinkStage(g, mainFileIdx)
-    return
-  else:
-    rawMessage(g.config, errGenerated,
-      "the per-module NIF backend requires --icBackendStage:cg|merge|emit|link")
+    if not g.config.hcrOn:
+      extccomp.writeJsonBuildInstructions(g.config, g.cachedFiles)

compiler/nifgen.nim

@@ -983,7 +983,7 @@ proc genericParamToNif(n: PNode; parent: PNode; c: var TranslationContext) =
     toNif n, parent, c
 
 proc addExternName(sym: PSym; c: var TranslationContext) =
-  if sym.loc.snippet != "":
+  if sym.loc.snippet != nil:
     c.b.addStrLit sym.loc.snippet
   else:
     c.b.addStrLit sym.name.s

compiler/nilcheck.nim

@@ -183,6 +183,12 @@ func `<`*(a: ExprIndex, b: ExprIndex): bool =
 func `<=`*(a: ExprIndex, b: ExprIndex): bool =
   a.int16 <= b.int16
 
+func `>`*(a: ExprIndex, b: ExprIndex): bool =
+  a.int16 > b.int16
+
+func `>=`*(a: ExprIndex, b: ExprIndex): bool =
+  a.int16 >= b.int16
+
 func `==`*(a: ExprIndex, b: ExprIndex): bool =
   a.int16 == b.int16
 

compiler/nim.cfg

@@ -12,8 +12,7 @@ define:nimPreviewNonVarDestructor
 define:nimPreviewCheckedClose
 define:nimPreviewAsmSemSymbol
 define:nimPreviewCStringComparisons
-#define:nimPreviewDuplicateModuleError
-# Incompatible with Nimony's compat2.nim for now
+define:nimPreviewDuplicateModuleError
 
 threads:off
 
@@ -66,7 +65,3 @@ define:useStdoutAsStdmsg
 @if nimHasVtables:
   experimental:vtables
 @end
-
-@if nimHasImplicitRangeConversion:
-  warning[ImplicitRangeConversion]:off
-@end

compiler/nim.nim

@@ -28,13 +28,10 @@ import
   commands, options, msgs, extccomp, main, idents, lineinfos, cmdlinehelper,
   pathutils, modulegraphs
 
-from ast2nif import registerNifAstTags
-from icconfig import ensureIcConfig
-
 from std/browsers import openDefaultBrowser
 from nodejs import findNodeJs
 
-when defined(tinyc): # == hasTinyCBackend; spelled out for the IC dep scanner
+when hasTinyCBackend:
   import tccgen
 
 when defined(profiler) or defined(memProfiler):
@@ -99,11 +96,6 @@ proc getNimRunExe(conf: ConfigRef): string =
     result = ""
 
 proc handleCmdLine(cache: IdentCache; conf: ConfigRef) =
-  # NIF tag registration must not depend on module init order — the IC-built
-  # compiler orders module init calls differently and the top-level
-  # `registerTag` initializers then ran against a not-yet-initialized pool,
-  # corrupting every written NIF (see registerNifAstTags).
-  registerNifAstTags()
   let self = NimProg(
     supportsStdinFile: true,
     processCmdLine: processCmdLine
@@ -115,14 +107,6 @@ proc handleCmdLine(cache: IdentCache; conf: ConfigRef) =
 
   self.processCmdLineAndProjectPath(conf)
 
-  # `nim ic` driver: ensure the precompiled config exists (produced by a separate
-  # `nim icconfig` process, skipped when nothing changed) BEFORE config loading,
-  # so `loadConfigs` replays it instead of re-parsing the `nim.cfg` chain — the
-  # driver runs on the exact same config its children will. See icconfig.nim.
-  when not defined(nimKochBootstrap):
-    if conf.cmd == cmdIc:
-      ensureIcConfig(conf)
-
   var graph = newModuleGraph(cache, conf)
   if not self.loadConfigsAndProcessCmdLine(cache, conf, graph):
     return
@@ -137,11 +121,6 @@ proc handleCmdLine(cache: IdentCache; conf: ConfigRef) =
         conf.cmd in {cmdGendepend, cmdNifC, cmdIc, cmdM}:
       initOrcDefines(conf)
 
-  if conf.selectedStrings == stringSso and
-      conf.selectedGC notin {gcArc, gcOrc, gcYrc, gcAtomicArc}:
-    rawMessage(conf, errGenerated,
-      "--strings:sso requires --mm:arc, --mm:orc, --mm:yrc, or --mm:atomicArc")
-
   mainCommand(graph)
   if conf.hasHint(hintGCStats): echo(GC_getStatistics())
   #echo(GC_getStatistics())

compiler/nimconf.nim

@@ -11,7 +11,7 @@
 
 import
   llstream, commands, msgs, lexer, ast,
-  options, idents, wordrecg, lineinfos, pathutils, scriptconfig, icconfig
+  options, idents, wordrecg, lineinfos, pathutils, scriptconfig
 
 import std/[os, strutils, strtabs]
 
@@ -246,16 +246,6 @@ proc getSystemConfigPath*(conf: ConfigRef; filename: RelativeFile): AbsoluteFile
 
 proc loadConfigs*(cfg: RelativeFile; cache: IdentCache; conf: ConfigRef; idgen: IdGenerator) =
   setDefaultLibpath(conf)
-  # The `nim ic` driver and its `nim m`/`nim nifc` children replay the precompiled
-  # config (produced once by a separate `nim icconfig` process — see
-  # `icconfig.ensureIcConfig`, which sets `icPreparsedConfig` for the driver
-  # before this runs; the children get it as a forwarded `--icPreparsedConfig`
-  # argument) instead of re-reading the `nim.cfg` chain and re-running
-  # `config.nims` in the VM. A missing/format-incompatible artifact returns false:
-  # fall through to a normal parse (this is also the path the `nim icconfig`
-  # producer itself takes, since it runs with no `icPreparsedConfig`).
-  if conf.icPreparsedConfig.len > 0 and applyIcConfig(conf, conf.icPreparsedConfig):
-    return
   template readConfigFile(path) =
     let configPath = path
     conf.currentConfigDir = configPath.splitFile.dir.string

compiler/options.nim

@@ -29,32 +29,6 @@ const
 
   nimEnableCovariance* = defined(nimEnableCovariance)
 
-  icFormatVersion* = "6"
-    ## Version of the IC cache format (the sem-NIF module layout written by
-    ## ast2nif.nim plus the iface/impl/edges side files). Bump it whenever
-    ## that layout changes: `commandIc` wipes a nimcache whose `ic.version`
-    ## stamp differs, instead of letting a newer reader mis-parse records
-    ## written by an older compiler (nifmake's rebuild check is mtime-only
-    ## and knows nothing about format changes).
-    ## v2: iface cookie hashes routine SIGNATURES only (no inline-semantics
-    ## body folding); body access now records a NeedsImpl edge instead. A v1
-    ## cache mixes body-sensitive and body-insensitive cookies, so it must be
-    ## wiped rather than warm-rebuilt.
-    ## v3: added the `.s.deps` sidecar (real post-sem imports) and switched the
-    ## macro-generated-import discovery from `icmissing.txt` to it.
-    ## v4: backend C-name scheme change — the module suffix is now the trailing
-    ## token (`name_u<disamb>__<suffix>`, was `name__<suffix>_u<disamb>`), so
-    ## cached `.c.nif` artifacts hold incompatible names and must be wiped.
-    ## v5: data definitions (consts, RTTI) are now wrapped in droppable `'d'`
-    ## cdef directives with an always-present extern declaration, so the
-    ## per-module merge stage can assign them a single owner; old `.c.nif`
-    ## artifacts lack the wrappers.
-    ## v6: `signatureHash`/`hashType` of a builtin type class (`object`, `tuple`,
-    ## `proc`, ...) no longer mixes in the placeholder son's process-local type
-    ## id, so its hash is stable across the NIF boundary (was breaking
-    ## nim-serialization's auto-serialization lookup under IC). The sem-NIF
-    ## macrocache entries and baked generic-instance bodies hold the old hashes.
-
 type                          # please make sure we have under 32 options
                               # (improves code efficiency a lot!)
   TOption* = enum             # **keep binary compatible**
@@ -94,7 +68,6 @@ type                          # please make sure we have under 32 options
     optUseNimcache,           # save artifacts (including binary) in $nimcache
     optStyleHint,             # check that the names adhere to NEP-1
     optStyleError,            # enforce that the names adhere to NEP-1
-    optStyleWarning,          # emit style checks as warnings
     optStyleUsages,           # only enforce consistent **usages** of the symbol
     optSkipSystemConfigFile,  # skip the system's cfg/nims config file
     optSkipProjConfigFile,    # skip the project's cfg/nims config file
@@ -137,7 +110,6 @@ type                          # please make sure we have under 32 options
     optEnableDeepCopy         # ORC specific: enable 'deepcopy' for all types.
     optShowNonExportedFields  # for documentation: show fields that are not exported
     optJsBigInt64             # use bigints for 64-bit integers in JS
-    optDocRaw                 # for documentation: Don't render markdown for JSON output
     optItaniumMangle          # mangling follows the Itanium spec
     optCompress               # turn on AST compression by converting it to NIF
     optWithinConfigSystem     # we still compile within the configuration system
@@ -183,6 +155,7 @@ type
     cmdCheck # semantic checking for whole project
     cmdM     # only compile a single
     cmdParse # parse a single file (for debugging)
+    cmdRod # .rod to some text representation (for debugging)
     cmdIdeTools # ide tools (e.g. nimsuggest)
     cmdNimscript # evaluate nimscript
     cmdDoc0
@@ -205,7 +178,6 @@ type
     cmdCompileToNif
     cmdNifC  # generate C code from NIF files
     cmdIc  # generate .build.nif for nifmake
-    cmdIcConfig # `nim ic`'s precompiled-config producer (writes ic_config.cfg.nif)
 
 const
   cmdBackends* = {cmdCompileToC, cmdCompileToCpp, cmdCompileToOC,
@@ -222,7 +194,6 @@ type
     gcRegions = "regions"
     gcArc = "arc"
     gcOrc = "orc"
-    gcYrc = "yrc"       # thread-safe ORC (concurrent cycle collector)
     gcAtomicArc = "atomicArc"
     gcMarkAndSweep = "markAndSweep"
     gcHooks = "hooks"
@@ -286,14 +257,6 @@ type
       ## Old transformation for closures in JS backend
     noPanicOnExcept
       ## don't panic on bare except
-    procParamTypeBackendAliases
-      ## Keep the old proc type compatibility rules that ignore backend
-      ## c type aliases.
-    injectedSymbolRedefinition
-      ## Allow a template to inject a symbol *definition* that is then emitted
-      ## more than once (e.g. a `typed` argument captured by a `{.dirty.}`
-      ## template and re-emitted). This is a redefinition and rejected by
-      ## default; enabling this restores the old, unsound behavior. See #25693.
 
   SymbolFilesOption* = enum
     disabledSf, writeOnlySf, readOnlySf, v2Sf, stressTest
@@ -302,10 +265,6 @@ type
     ccNone, ccGcc, ccNintendoSwitch, ccLLVM_Gcc, ccCLang, ccBcc, ccVcc,
     ccTcc, ccEnv, ccIcl, ccIcc, ccClangCl, ccHipcc, ccNvcc
 
-  StringsMode* = enum
-    stringDefault = "default"
-    stringSso = "sso"
-
   ExceptionSystem* = enum
     excNone,   # no exception system selected yet
     excSetjmp, # setjmp based exception handling
@@ -405,55 +364,12 @@ type
     implicitCmd*: bool # whether some flag triggered an implicit `command`
     selectedGC*: TGCMode       # the selected GC (+)
     exc*: ExceptionSystem
-    selectedStrings*: StringsMode
     hintProcessingDots*: bool # true for dots, false for filenames
     verbosity*: int            # how verbose the compiler is
     numberOfProcessors*: int   # number of processors
     lastCmdTime*: float        # when caas is enabled, we measure each command
     symbolFiles*: SymbolFilesOption
     ic*: bool # whether ic is enabled
-    icGroup*: HashSet[string] # under `nim m`: absolute paths of the modules in
-                              # this strongly-connected import group. They are all
-                              # compiled from source in one process (so mutual
-                              # recursion resolves in-memory) and each gets its NIF
-                              # written, instead of being loaded from a precompiled
-                              # NIF. See `compiler/deps.nim` (SCC grouping).
-    icProject*: string        # under `nim m`/`nim nifc`: absolute path of the
-                              # ORIGINAL project file. The child's own project file
-                              # is the module being compiled, which would make that
-                              # module's package the "main package" and unfilter
-                              # foreign-package diagnostics; the real project
-                              # restores whole-program filtering semantics.
-    icPreparsedConfig*: string # under the `nim ic` driver and its `nim m`/`nim nifc`
-                              # children: path of the precompiled config artifact.
-                              # When set, `loadConfigs` replays the recorded
-                              # config-file switches from it instead of re-reading
-                              # the `nim.cfg` chain and re-running `config.nims`
-                              # (which the VM makes expensive) per process. The
-                              # artifact itself is produced by a separate
-                              # `nim icconfig` process (see `cmdIcConfig`).
-    icConfigOut*: string      # under `nim icconfig`: the path to write the
-                              # precompiled config artifact to (set via `--o`).
-    icConfigSwitches*: seq[tuple[switch, arg: string]]
-                              # the config-file (`passPP`) switches applied while
-                              # loading config, in order. Recorded by every nim
-                              # process; only the `ic` driver serialises them.
-                              # Path-search switches are excluded — the driver
-                              # forwards the resolved `searchPaths` as `--path`.
-    icBackendStage*: string   # under `nim nifc`: which stage of the per-module
-                              # backend this invocation runs — "cg" (codegen one
-                              # module to its `.c.nif`), "merge" (global liveness
-                              # + owner assignment across all `.c.nif`), "emit"
-                              # (render one module's `.c` from its `.c.nif` + the
-                              # merge decision), "link" (cc + link every emitted
-                              # `.c`). Empty = whole-program backend (load all,
-                              # codegen+DCE+cc+link in one process). The stages
-                              # are wired as nifmake rules by `deps.nim`'s backend
-                              # build file. See `compiler/nifbackend.nim`.
-    icBackendModule*: string  # under `nim nifc` with icBackendStage in {cg,emit}:
-                              # the NIF module suffix this invocation codegens or
-                              # emits. The other modules are loaded only so types
-                              # resolve; their definitions are referenced extern.
     spellSuggestMax*: int # max number of spelling suggestions for typos
 
     cppDefines*: HashSet[string] # (*)
@@ -500,12 +416,6 @@ type
     lastMsgWasDot*: set[StdOrrKind] # the last compiler message was a single '.'
     projectMainIdx*: FileIndex # the canonical path id of the main module
     projectMainIdx2*: FileIndex # consider merging with projectMainIdx
-    isMainModule*: bool # `nim m`/IC only: whether the single module being
-                        # semantically checked is the program's real entry point.
-                        # Under IC every module is compiled via `nim m` (which sets
-                        # `sfMainModule` so the module writes its own NIF), so
-                        # `sfMainModule` can no longer answer `isMainModule`. The IC
-                        # build file passes `--isMainModule:on` for the root module.
     command*: string # the main command (e.g. cc, check, scan, etc)
     commandArgs*: seq[string] # any arguments after the main command
     commandLine*: string
@@ -662,7 +572,6 @@ proc newConfigRef*(): ConfigRef =
     arcToExpand: newStringTable(modeStyleInsensitive),
     m: initMsgConfig(),
     cppDefines: initHashSet[string](),
-    icGroup: initHashSet[string](),
     headerFile: "", features: {}, legacyFeatures: {},
     configVars: newStringTable(modeStyleInsensitive),
     symbols: newStringTable(modeStyleInsensitive),
@@ -738,7 +647,6 @@ proc isDefined*(conf: ConfigRef; symbol: string): bool =
     of "x86": result = conf.target.targetCPU == cpuI386
     of "itanium": result = conf.target.targetCPU == cpuIa64
     of "x8664": result = conf.target.targetCPU == cpuAmd64
-    of "wasm": result = conf.target.targetCPU in {cpuWasm32, cpuWasm64}
     of "posix", "unix":
       result = conf.target.targetOS in {osLinux, osMorphos, osSkyos, osIrix, osPalmos,
                             osQnx, osAtari, osAix,
@@ -788,7 +696,6 @@ template quitOrRaise*(conf: ConfigRef, msg = "") =
 
 proc importantComments*(conf: ConfigRef): bool {.inline.} = conf.cmd in cmdDocLike + {cmdIdeTools}
 proc usesWriteBarrier*(conf: ConfigRef): bool {.inline.} = conf.selectedGC >= gcRefc
-proc usesSso*(conf: ConfigRef): bool {.inline.} = conf.selectedStrings == stringSso
 
 template compilationCachePresent*(conf: ConfigRef): untyped =
   false
@@ -1139,9 +1046,6 @@ proc isDynlibOverride*(conf: ConfigRef; lib: string): bool =
 proc showNonExportedFields*(conf: ConfigRef) =
   incl(conf.globalOptions, optShowNonExportedFields)
 
-proc docRawOutput*(conf: ConfigRef) =
-  incl(conf.globalOptions, optDocRaw)
-
 proc expandDone*(conf: ConfigRef): bool =
   result = conf.ideCmd == ideExpand and conf.expandLevels == 0 and conf.expandProgress
 

compiler/parser.nim

@@ -54,10 +54,7 @@ import
 
 when not defined(nimCustomAst):
   import ast
-when defined(nimCustomAst):
-  # NOTE: explicit negated `when` rather than `else:` — nifler's dep scanner
-  # guards `when`/`elif` imports with their condition but emits `else:` imports
-  # unconditionally, which would wrongly schedule this module under `nim ic`.
+else:
   import plugins / customast
 
 import std/strutils
@@ -2244,17 +2241,14 @@ proc parseTypeClassParam(p: var Parser): PNode =
 
 proc parseTypeClass(p: var Parser): PNode =
   #| conceptParam = ('var' | 'out' | 'ptr' | 'ref' | 'static' | 'type')? symbol
-  #| conceptDecl = 'concept' (conceptParam ^* ',' (pragma)?)? ('of' typeDesc ^* ',')?
+  #| conceptDecl = 'concept' conceptParam ^* ',' (pragma)? ('of' typeDesc ^* ',')?
   #|               &IND{>} stmt
   result = newNodeP(nkTypeClassTy, p)
   getTok(p)
   if p.tok.tokType == tkComment:
     skipComment(p, result)
 
-  if p.tok.tokType == tkOf and p.tok.indent < 0:
-    # new-styled `concept of A, B` on the same line as `concept`
-    result.add(p.emptyNode)
-  elif p.tok.indent < 0:
+  if p.tok.indent < 0:
     var args = newNodeP(nkArgList, p)
     result.add(args)
     args.add(p.parseTypeClassParam)
@@ -2280,10 +2274,9 @@ proc parseTypeClass(p: var Parser): PNode =
     result.add(p.emptyNode)
   if p.tok.tokType == tkComment:
     skipComment(p, result)
-  # an initial IND{>} HAS to follow, unless this concept inherits requirements:
+  # an initial IND{>} HAS to follow:
   if not realInd(p):
-    let hasParents = result[2].kind != nkEmpty
-    if result.isNewStyleConcept and not hasParents:
+    if result.isNewStyleConcept:
       parMessage(p, "routine expected, but found '$1' (empty new-styled concepts are not allowed)", p.tok)
     result.add(p.emptyNode)
   else:

compiler/passes.nim

@@ -148,6 +148,11 @@ proc processModule*(graph: ModuleGraph; module: PSym; idgen: IdGenerator;
     closeParser(p)
     if s.kind != llsStdIn: break
   closePasses(graph, a)
+  if graph.config.backend notin {backendC, backendCpp, backendObjc}:
+    # We only write rod files here if no C-like backend is active.
+    # The C-like backends have been patched to support the IC mechanism.
+    # They are responsible for closing the rod files. See `cbackend.nim`.
+    closeRodFile(graph, module)
   result = true
 
 proc compileModule*(graph: ModuleGraph; fileIdx: FileIndex; flags: TSymFlags, fromModule: PSym = nil): PSym =
@@ -163,10 +168,22 @@ proc compileModule*(graph: ModuleGraph; fileIdx: FileIndex; flags: TSymFlags, fr
       elif graph.config.projectIsCmd: s = llStreamOpen(graph.config.cmdInput)
     discard processModule(graph, result, idGeneratorFromModule(result), s)
   if result == nil:
-    result = newModule(graph, fileIdx)
-    result.incl flags
-    registerModule(graph, result)
-    processModuleAux("import")
+    var cachedModules: seq[FileIndex] = @[]
+    result = moduleFromRodFile(graph, fileIdx, cachedModules)
+    let filename = AbsoluteFile toFullPath(graph.config, fileIdx)
+    if result == nil:
+      result = newModule(graph, fileIdx)
+      result.incl flags
+      registerModule(graph, result)
+      processModuleAux("import")
+    else:
+      if sfSystemModule in flags:
+        graph.systemModule = result
+      partialInitModule(result, graph, fileIdx, filename)
+    for m in cachedModules:
+      registerModuleById(graph, m)
+      replayStateChanges(graph.packed.pm[m.int].module, graph)
+      replayGenericCacheInformation(graph, m.int)
   elif graph.isDirty(result):
     result.excl sfDirty
     # reset module fields:

compiler/pipelines.nim

@@ -15,7 +15,7 @@ import ../dist/checksums/src/checksums/sha1
 when not defined(leanCompiler):
   import jsgen, docgen2
 
-import std/[syncio, objectdollar, assertions, tables, strutils, strtabs, sets, intsets]
+import std/[syncio, objectdollar, assertions, tables, strutils, strtabs]
 import renderer
 import ic/replayer
 
@@ -242,16 +242,8 @@ proc processPipelineModule*(graph: ModuleGraph; module: PSym; idgen: IdGenerator
     raiseAssert "use setPipeLinePass to set a proper PipelinePass"
 
   when not defined(nimKochBootstrap):
-    # For cmdM: only write NIF for the main module, not for imported modules
-    # (imported modules should be loaded from existing NIF files). Members of the
-    # current strongly-connected import group (`--icGroup`) are the exception:
-    # they are compiled from source here, so each must write its own NIF.
-    let shouldWriteNif = (optCompress in graph.config.globalOptions) or
-                         (graph.config.cmd == cmdM and
-                          (sfMainModule in module.flags or
-                           (graph.config.icGroup.len > 0 and
-                            toFullPath(graph.config, module.position.FileIndex) in graph.config.icGroup)))
-    if shouldWriteNif and not graph.config.isDefined("nimscript"):
+    if (optCompress in graph.config.globalOptions or graph.config.cmd == cmdM) and
+       not graph.config.isDefined("nimscript"):
       topLevelStmts.add finalNode
       # Collect replay actions from both pragma computations and VM state diff
       var replayActions: seq[PNode] = @[]
@@ -264,99 +256,22 @@ proc processPipelineModule*(graph: ModuleGraph; module: PSym; idgen: IdGenerator
           if m == module:
             replayActions.add n
 
-      # NeedsImpl edge recording: which modules' bodies this process consumed
-      # at compile time (VM/getImpl). For an --icGroup cycle every member gets
-      # the union; intra-group entries are filtered by the writer.
-      var implDeps: seq[int] = @[]
-      for id in graph.icImplDeps: implDeps.add id
-      # Generic-instance OFFERS: every instance THIS module created, so a
-      # consumer reuses it rather than re-instantiating in its own scope (which
-      # cannot see symbols visible only at the generic's definition site — e.g.
-      # a distinct type's `==`). See ast2nif.writeNifModule / moduleFromNifFile.
-      var genericOffers: seq[tuple[generic, inst: PSym;
-                                   concreteTypes: seq[PType]; genericParamsCount: int]] = @[]
-      for genItemId, instList in graph.procInstCache:
-        for inst in instList:
-          if inst.sym != nil and inst.sym.itemId.module == module.position and
-              inst.sym.instantiatedFrom != nil and inst.compilesId == 0:
-            # `concreteTypes` is pre-sized to `paramsLen+gp.len`; a tail slot can
-            # stay nil (e.g. fewer materialized params than `paramsLen`). Such an
-            # offer can't be serialized — skip it (the consumer re-instantiates,
-            # the prior behaviour) rather than emit a nil type reference.
-            var hasNil = false
-            for ct in inst.concreteTypes:
-              if ct == nil: hasNil = true; break
-            if not hasNil:
-              genericOffers.add (inst.sym.instantiatedFrom, inst.sym,
-                                 inst.concreteTypes, inst.genericParamsCount)
-      # The module's REAL resolved direct imports (incl. macro/template-generated
-      # ones with no surviving syntactic node). Passed to writeNifModule so the
-      # NIF `deps` section is complete (the backend closure walk needs it), and
-      # reused below for the `.s.deps` sidecar (frontend graph re-derivation).
-      let resolvedImportDeps = graph.importDeps.getOrDefault(module.position.FileIndex, @[])
-      writeNifModule(graph.config, module.position.int32, topLevelStmts, graph.opsLog,
-                     replayActions, implDeps, reexportedModuleSyms(graph, module),
-                     genericOffers, resolvedImportDeps)
-      # The module's REAL direct imports (incl. macro-generated) for `nim ic`'s
-      # graph re-derivation; see ast2nif.writeSemDeps / semdata.addImportFileDep.
-      var semDepPaths: seq[string] = @[]
-      for f in resolvedImportDeps:
-        semDepPaths.add toFullPath(graph.config, f)
-      writeSemDeps(graph.config, module.position.int32, semDepPaths)
+      writeNifModule(graph.config, module.position.int32, topLevelStmts, graph.opsLog, replayActions)
 
+  if graph.config.backend notin {backendC, backendCpp, backendObjc} and graph.config.cmd != cmdM:
+    # We only write rod files here if no C-like backend is active.
+    # The C-like backends have been patched to support the IC mechanism.
+    # They are responsible for closing the rod files. See `cbackend.nim`.
+    # cmdM uses NIF files only, not ROD files.
+    closeRodFile(graph, module)
   result = true
 
-proc loadedDefSym(defs: PNode): PSym =
-  ## The defined symbol of a let/var entry as it loads back from a NIF: the
-  ## section child is a bare `nkSym` (the `(sd …)` reference), but be defensive
-  ## about the from-source shapes too (`nkIdentDefs`, a pragma-wrapped name).
-  case defs.kind
-  of nkSym: result = defs.sym
-  of nkPragmaExpr:
-    result = if defs.len > 0: loadedDefSym(defs[0]) else: nil
-  of nkIdentDefs, nkConstDef:
-    result = if defs.len > 0: loadedDefSym(defs[0]) else: nil
-  else: result = nil
-
-proc initLoadedCompileTimeGlobals(graph: ModuleGraph; module: PSym; topLevel: PNode) =
-  ## Eagerly initialize the compile-time globals (`let/var {.compileTime.}`) of a
-  ## module restored from a NIF. In a normal sem these VM slots are filled by
-  ## `setupCompileTimeVar` (semstmts) as the section is semchecked; a NIF-loaded
-  ## module is never semchecked, so without this a macro or compile-time proc that
-  ## reads such a global finds a nil slot. The lazy `vmgen.genGlobalInit` fallback
-  ## is order-fragile across proc boundaries (it emits the init at the first
-  ## VM-gen'd reference, which need not be the first one executed), so the init has
-  ## to happen here, once, before any of the module's code can run. The symbol's
-  ## own `ast` is the `nkIdentDefs` (initializer included); re-wrap it in a section
-  ## exactly as semstmts does and hand it to the same evaluator.
-  if topLevel == nil: return
-  let idgen = idGeneratorFromModule(module)
-  for stmt in topLevel:
-    if stmt.kind notin {nkLetSection, nkVarSection}: continue
-    for defs in stmt:
-      let s = loadedDefSym(defs)
-      if s != nil and s.kind in {skLet, skVar} and
-         {sfCompileTime, sfGlobal} <= s.flags and
-         s.ast != nil and s.ast.kind == nkIdentDefs:
-        var sect = newNodeI(stmt.kind, s.info)
-        sect.add s.ast
-        setupCompileTimeVar(module, idgen, graph, sect)
-
 proc compilePipelineModule*(graph: ModuleGraph; fileIdx: FileIndex; flags: TSymFlags; fromModule: PSym = nil): PSym =
   var flags = flags
   if fileIdx == graph.config.projectMainIdx2: flags.incl sfMainModule
   result = graph.getModule(fileIdx)
 
   template processModuleAux(moduleStatus) =
-    when defined(icDbg):
-      block:
-        let dbgf = open("/tmp/defdbg.txt", fmAppend)
-        dbgf.writeLine toFullPath(graph.config, fileIdx) &
-          " nimStackTraceOverride=" & $isDefined(graph.config, "nimStackTraceOverride") &
-          " nimscript=" & $isDefined(graph.config, "nimscript") &
-          " optCompress=" & $(optCompress in graph.config.globalOptions) &
-          " cmd=" & $graph.config.cmd
-        dbgf.close()
     onProcessing(graph, fileIdx, moduleStatus, fromModule = fromModule)
     var s: PLLStream = nil
     if sfMainModule in flags:
@@ -364,74 +279,24 @@ proc compilePipelineModule*(graph: ModuleGraph; fileIdx: FileIndex; flags: TSymF
       elif graph.config.projectIsCmd: s = llStreamOpen(graph.config.cmdInput)
     discard processPipelineModule(graph, result, idGeneratorFromModule(result), s)
   if result == nil:
+    var cachedModules: seq[FileIndex] = @[]
     when not defined(nimKochBootstrap):
       # For cmdM: load imports from NIF files (but compile the main module from source)
-      # Skip when withinSystem is true (compiling system.nim itself).
-      # Also skip for members of the current strongly-connected import group
-      # (`--icGroup`): those are mutually recursive with the main module and have
-      # no precompiled NIF yet, so they must be compiled from source in this same
-      # process (falling through below) — that resolves the cycle in-memory, the
-      # same way the non-incremental compiler handles recursive module imports.
+      # Skip when withinSystem is true (compiling system.nim itself)
       if graph.config.cmd == cmdM and
          sfMainModule notin flags and
          not graph.withinSystem and
-         not graph.config.isDefined("nimscript") and
-         (graph.config.icGroup.len == 0 or
-          toFullPath(graph.config, fileIdx) notin graph.config.icGroup):
+         not graph.config.isDefined("nimscript"):
         let precomp = moduleFromNifFile(graph, fileIdx)
         if precomp.module == nil:
           let nifPath = toNifFilename(graph.config, fileIdx)
-          # Macro-generated imports (e.g. chronicles' parseStmt("import
-          # chronicles/textlines") driven by the chronicles_sinks define) are
-          # invisible to the static scanner, so this module's NIF was never
-          # built. The importer already recorded this import via
-          # addImportFileDep, so flush every module's `.s.deps`: `nim ic` reads
-          # it, re-derives the graph with the missing node + edge, and reruns
-          # the frontend. We still error — this process cannot finish sem
-          # without the import — but the discovery is structured data now, not
-          # a side-channel file.
-          for importer, deps in graph.importDeps.pairs:
-            var paths: seq[string] = @[]
-            for f in deps: paths.add toFullPath(graph.config, f)
-            writeSemDeps(graph.config, importer.int32, paths)
-          globalError(graph.config, unknownLineInfo,
+          localError(graph.config, unknownLineInfo,
             "nim m requires precompiled NIF for import: " & toFullPath(graph.config, fileIdx) &
             " (expected: " & nifPath & ")")
           return nil  # Don't fall through to compile from source
-        else:
-          # Module successfully loaded from NIF file - use it and skip processing
-          result = precomp.module
-          if sfSystemModule in flags:
-            graph.systemModule = result
-          partialInitModule(result, graph, fileIdx, AbsoluteFile(toFullPath(graph.config, fileIdx)))
-          # Replay the module's recorded state changes: macro-cache operations
-          # (std/macrocache puts/incs/adds/incls) plus a few pragmas. The loader
-          # parsed them into `precomp.topLevel` (mixed with other top-level nodes),
-          # so filter to the replay actions. A loaded module's `ast` is never
-          # rebuilt, so this used to be skipped (`result.ast == nil`) and a
-          # NIF-loaded module's macro cache was lost — e.g. nim-serialization's
-          # flavor registration became invisible to dependents (`DefaultFlavor:
-          # automatic serialization is not enabled`).
-          var replayList = newNodeI(nkStmtList, result.info)
-          for n in precomp.topLevel:
-            # Only macro-cache ops (put/inc/add/incl). The pragma replay actions
-            # (compile/link/passc/hint/...) are a backend/link concern handled by
-            # the nifc closure, and re-emitting a loaded module's hints/warnings on
-            # every import would be wrong — so they are deliberately skipped here.
-            if n.kind == nkReplayAction and n.len >= 1 and n[0].kind == nkStrLit and
-               n[0].strVal in ["put", "inc", "add", "incl"]:
-              replayList.add n
-          # Plus the macro-cache actions of the module's transitive import closure
-          # (collected by the moduleFromNifFile call above via loadTransitiveHooks),
-          # so a flavor/type registered in an indirectly-imported module is visible.
-          for n in graph.transitiveReplayActions: replayList.add n
-          graph.transitiveReplayActions.setLen 0
-          if replayList.len > 0:
-            replayStateChanges(result, graph, replayList)
-          # Fill the VM slots of the module's `{.compileTime.}` globals now (sem
-          # would have, but a NIF-loaded module is never semchecked).
-          initLoadedCompileTimeGlobals(graph, result, precomp.topLevel)
-          return result  # Return early, don't process from source
+    if result == nil and graph.config.cmd != cmdM:
+      # Fall back to ROD file loading (not used for cmdM which uses NIF only)
+      result = moduleFromRodFile(graph, fileIdx, cachedModules)
     let path = toFullPath(graph.config, fileIdx)
     let filename = AbsoluteFile path
     # it could be a stdinfile/cmdfile
@@ -450,6 +315,16 @@ proc compilePipelineModule*(graph: ModuleGraph; fileIdx: FileIndex; flags: TSymF
         registerModule(graph, result)
         processModuleAux("import")
       partialInitModule(result, graph, fileIdx, filename)
+    for m in cachedModules:
+      registerModuleById(graph, m)
+      if graph.config.cmd == cmdM:
+        # cmdM uses NIF files - replay from module AST loaded by loadNifModule
+        let module = graph.getModule(m)
+        if module != nil and module.ast != nil:
+          replayStateChanges(module, graph)
+      else:
+        replayStateChanges(graph.packed.pm[m.int].module, graph)
+        replayGenericCacheInformation(graph, m.int)
   elif graph.isDirty(result):
     result.excl sfDirty
     # reset module fields:
@@ -496,14 +371,7 @@ proc compilePipelineProject*(graph: ModuleGraph; projectFileIdx = InvalidFileIdx
   let projectFile = if projectFileIdx == InvalidFileIdx: conf.projectMainIdx else: projectFileIdx
   conf.projectMainIdx2 = projectFile
 
-  var packSym = getPackage(graph, projectFile)
-  if graph.config.cmd in {cmdM, cmdNifC} and graph.config.icProject.len > 0:
-    # per-module IC children: the process' project file is the MODULE being
-    # compiled, which would make its package the "main package" and unfilter
-    # foreign-package diagnostics (a vendored package's hintAsError promotion
-    # then aborts builds the whole-program compilation accepts). Use the
-    # original project, forwarded by deps.nim via --icproject.
-    packSym = getPackage(graph, fileInfoIdx(graph.config, AbsoluteFile graph.config.icProject))
+  let packSym = getPackage(graph, projectFile)
   graph.config.mainPackageId = packSym.getPackageId
   graph.importStack.add projectFile
 
@@ -514,11 +382,9 @@ proc compilePipelineProject*(graph: ModuleGraph; projectFileIdx = InvalidFileIdx
   elif graph.config.cmd == cmdM:
     # For cmdM: load system.nim from NIF first, then compile the main module
     connectPipelineCallbacks(graph)
-    # Record the main module so the IC loader won't materialise duplicate stubs
-    # for its own symbols when a dependency (e.g. system) re-exports them.
-    setIcMainModule(projectFile)
     graph.config.m.systemFileIdx = fileInfoIdx(graph.config,
         graph.config.libpath / RelativeFile"system.nim")
+    var cachedModules: seq[FileIndex] = @[]
     when not defined(nimKochBootstrap):
       let precomp = moduleFromNifFile(graph, graph.config.m.systemFileIdx)
       graph.systemModule = precomp.module

compiler/pipelineutils.nim

@@ -1,4 +1,3 @@
-import std/intsets
 import ast, options, lineinfos, pathutils, msgs, modulegraphs, packages
 
 proc skipCodegen*(config: ConfigRef; n: PNode): bool {.inline.} =
@@ -24,3 +23,4 @@ proc prepareConfigNotes*(graph: ModuleGraph; module: PSym) =
 
 proc moduleHasChanged*(graph: ModuleGraph; module: PSym): bool {.inline.} =
   result = true
+  #module.id >= 0 or isDefined(graph.config, "nimBackendAssumesChange")

compiler/platform.nim

@@ -211,7 +211,7 @@ type
     cpuPowerpc64el, cpuSparc, cpuVm, cpuHppa, cpuIa64, cpuAmd64, cpuMips,
     cpuMipsel, cpuArm, cpuArm64, cpuJS, cpuNimVM, cpuAVR, cpuMSP430,
     cpuSparc64, cpuS390x, cpuMips64, cpuMips64el, cpuRiscV32, cpuRiscV64,
-    cpuEsp, cpuWasm32, cpuE2k, cpuLoongArch64, cpuWasm64
+    cpuEsp, cpuWasm32, cpuE2k, cpuLoongArch64
 
 type
   TInfoCPU* = tuple[name: string, intSize: int, endian: Endianness,
@@ -249,8 +249,7 @@ const
     (name: "esp", intSize: 32, endian: littleEndian, floatSize: 64, bit: 32),
     (name: "wasm32", intSize: 32, endian: littleEndian, floatSize: 64, bit: 32),
     (name: "e2k", intSize: 64, endian: littleEndian, floatSize: 64, bit: 64),
-    (name: "loongarch64", intSize: 64, endian: littleEndian, floatSize: 64, bit: 64),
-    (name: "wasm64", intSize: 64, endian: littleEndian, floatSize: 64, bit: 64)]
+    (name: "loongarch64", intSize: 64, endian: littleEndian, floatSize: 64, bit: 64)]
 
 type
   Target* = object

compiler/pragmas.nim

@@ -21,6 +21,8 @@ import std/[os, math, strutils]
 when defined(nimPreviewSlimSystem):
   import std/assertions
 
+from ic / ic import addCompilerProc
+
 const
   FirstCallConv* = wNimcall
   LastCallConv* = wNoconv
@@ -567,7 +569,7 @@ proc processCompile(c: PContext, n: PNode) =
     n[i] = c.semConstExpr(c, n[i])
     case n[i].kind
     of nkStrLit, nkRStrLit, nkTripleStrLit:
-      when defined(gcArc) or defined(gcOrc) or defined(gcAtomicArc) or defined(gcYrc):
+      when defined(gcArc) or defined(gcOrc) or defined(gcAtomicArc):
         result = n[i].strVal
       else:
         shallowCopy(result, n[i].strVal)
@@ -765,6 +767,8 @@ proc markCompilerProc(c: PContext; s: PSym) =
   incl(s, sfCompilerProc)
   incl(s.flagsImpl, sfUsed)
   registerCompilerProc(c.graph, s)
+  if c.config.symbolFiles != disabledSf:
+    addCompilerProc(c.encoder, c.packedRepr, s)
 
 proc deprecatedStmt(c: PContext; outerPragma: PNode) =
   let pragma = outerPragma[1]

compiler/renderer.nim

@@ -14,7 +14,7 @@
 {.used.}
 
 import
-  lexer, options, idents, ast, msgs, lineinfos, wordrecg, trees
+  lexer, options, idents, ast, msgs, lineinfos, wordrecg
 
 import std/[strutils]
 
@@ -66,359 +66,6 @@ proc renderTree*(n: PNode, renderFlags: TRenderFlags = {}): string
 # determines how long the subtree will likely be, the second
 # phase appends to a buffer that will be the output.
 
-type
-  TPreferedDesc* = enum
-    preferName, # default
-    preferDesc, # probably should become what preferResolved is
-    preferExported,
-    preferModuleInfo, # fully qualified
-    preferGenericArg,
-    preferTypeName,
-    preferResolved, # fully resolved symbols
-    preferMixed,
-      # most useful, shows: symbol + resolved symbols if it differs, e.g.:
-      # tuple[a: MyInt{int}, b: float]
-    preferInlayHint,
-    preferInferredEffects,
-
-proc typeToString*(typ: PType; prefer: TPreferedDesc = preferName): string
-template `$`*(typ: PType): string = typeToString(typ)
-
-proc valueToString(a: PNode): string =
-  case a.kind
-  of nkCharLit, nkUIntLit..nkUInt64Lit:
-    result = $cast[uint64](a.intVal)
-  of nkIntLit..nkInt64Lit:
-    result = $a.intVal
-  of nkFloatLit..nkFloat128Lit: result = $a.floatVal
-  of nkStrLit..nkTripleStrLit: result = a.strVal
-  of nkStaticExpr: result = "static(" & a[0].renderTree & ")"
-  else: result = "<invalid value>"
-
-proc rangeToStr(n: PNode): string =
-  assert(n.kind == nkRange)
-  result = valueToString(n[0]) & ".." & valueToString(n[1])
-
-const preferToResolveSymbols = {preferName, preferTypeName, preferModuleInfo,
-  preferGenericArg, preferResolved, preferMixed, preferInlayHint, preferInferredEffects}
-
-
-const
-  typeToStr: array[TTypeKind, string] = ["None", "bool", "char", "empty",
-    "Alias", "typeof(nil)", "untyped", "typed", "typeDesc",
-    # xxx typeDesc=>typedesc: typedesc is declared as such, and is 10x more common.
-    "GenericInvocation", "GenericBody", "GenericInst", "GenericParam",
-    "distinct $1", "enum", "ordinal[$1]", "array[$1, $2]", "object", "tuple",
-    "set[$1]", "range[$1]", "ptr ", "ref ", "var ", "seq[$1]", "proc",
-    "pointer", "OpenArray[$1]", "string", "cstring", "Forward",
-    "int", "int8", "int16", "int32", "int64",
-    "float", "float32", "float64", "float128",
-    "uint", "uint8", "uint16", "uint32", "uint64",
-    "owned", "sink",
-    "lent ", "varargs[$1]", "UncheckedArray[$1]", "Error Type",
-    "BuiltInTypeClass", "UserTypeClass",
-    "UserTypeClassInst", "CompositeTypeClass", "inferred",
-    "and", "or", "not", "any", "static", "TypeFromExpr", "concept", # xxx bugfix
-    "void", "iterable"]
-
-proc addTypeFlags(name: var string, typ: PType) {.inline.} =
-  if tfNotNil in typ.flags: name.add(" not nil")
-
-proc isIntLit*(t: PType): bool {.inline.} =
-  result = t.kind == tyInt and t.n != nil and t.n.kind == nkIntLit
-
-proc isFloatLit*(t: PType): bool {.inline.} =
-  result = t.kind == tyFloat and t.n != nil and t.n.kind == nkFloatLit
-
-# TODO: It would be a good idea to kill the special state of a resolved
-# concept by switching to tyAlias within the instantiated procs.
-# Currently, tyAlias is always skipped with skipModifier, which means that
-# we can store information about the matched concept in another position.
-# Then builtInFieldAccess can be modified to properly read the derived
-# consts and types stored within the concept.
-template isResolvedUserTypeClass*(t: PType): bool =
-  tfResolved in t.flags
-
-proc typeToString(typ: PType, prefer: TPreferedDesc = preferName): string =
-  let preferToplevel = prefer
-  proc getPrefer(prefer: TPreferedDesc): TPreferedDesc =
-    if preferToplevel in {preferResolved, preferMixed}:
-      preferToplevel # sticky option
-    else:
-      prefer
-
-  proc typeToString(typ: PType, prefer: TPreferedDesc = preferName): string =
-    result = ""
-    let prefer = getPrefer(prefer)
-    let t = typ
-    if t == nil: return
-    if prefer in preferToResolveSymbols and t.sym != nil and
-         sfAnon notin t.sym.flags and t.kind notin {tySequence, tyInferred}:
-      if t.kind == tyInt and isIntLit(t):
-        if prefer == preferInlayHint:
-          result = t.sym.name.s
-        else:
-          result = t.sym.name.s & " literal(" & $t.n.intVal & ")"
-      elif t.kind == tyAlias and t.elementType.kind != tyAlias:
-        result = typeToString(t.elementType)
-      elif prefer in {preferResolved, preferMixed}:
-        case t.kind
-        of IntegralTypes + {tyFloat..tyFloat128} + {tyString, tyCstring}:
-          result = typeToStr[t.kind]
-        of tyGenericBody:
-          result = typeToString(t.last)
-        of tyCompositeTypeClass:
-          # avoids showing `A[any]` in `proc fun(a: A)` with `A = object[T]`
-          result = typeToString(t.last.last)
-        else:
-          result = t.sym.name.s
-        if prefer == preferMixed and result != t.sym.name.s:
-          result = t.sym.name.s & "{" & result & "}"
-      elif prefer in {preferName, preferTypeName, preferInlayHint, preferInferredEffects} or t.sym.owner.isNil:
-        # note: should probably be: {preferName, preferTypeName, preferGenericArg}
-        result = t.sym.name.s
-        if t.kind == tyGenericParam and t.genericParamHasConstraints:
-          result.add ": "
-          result.add t.elementType.typeToString
-      else:
-        result = t.sym.owner.name.s & '.' & t.sym.name.s
-      result.addTypeFlags(t)
-      return
-    case t.kind
-    of tyInt:
-      if not isIntLit(t) or prefer == preferExported:
-        result = typeToStr[t.kind]
-      else:
-        case prefer:
-        of preferGenericArg:
-          result = $t.n.intVal
-        of preferInlayHint:
-          result = "int"
-        else:
-          result = "int literal(" & $t.n.intVal & ")"
-    of tyGenericInst:
-      result = typeToString(t.genericHead) & '['
-      for needsComma, a in t.genericInstParams:
-        if needsComma: result.add(", ")
-        result.add(typeToString(a, preferGenericArg))
-      result.add(']')
-    of tyGenericInvocation:
-      result = typeToString(t.genericHead) & '['
-      for needsComma, a in t.genericInvocationParams:
-        if needsComma: result.add(", ")
-        result.add(typeToString(a, preferGenericArg))
-      result.add(']')
-    of tyGenericBody:
-      result = typeToString(t.typeBodyImpl) & '['
-      for i, a in t.genericBodyParams:
-        if i > 0: result.add(", ")
-        result.add(typeToString(a, preferTypeName))
-      result.add(']')
-    of tyTypeDesc:
-      if t.elementType.kind == tyNone: result = "typedesc"
-      else: result = "typedesc[" & typeToString(t.elementType) & "]"
-    of tyStatic:
-      if prefer == preferGenericArg and t.n != nil:
-        result = t.n.renderTree
-      else:
-        result = "static[" & (if t.hasElementType: typeToString(t.skipModifier) else: "") & "]"
-        if t.n != nil: result.add "(" & renderTree(t.n) & ")"
-    of tyUserTypeClass:
-      if t.sym != nil and t.sym.owner != nil:
-        if t.isResolvedUserTypeClass: return typeToString(t.last)
-        return t.sym.owner.name.s
-      else:
-        result = "<invalid tyUserTypeClass>"
-    of tyBuiltInTypeClass:
-      result =
-        case t.base.kind
-        of tyVar: "var"
-        of tyRef: "ref"
-        of tyPtr: "ptr"
-        of tySequence: "seq"
-        of tyArray: "array"
-        of tySet: "set"
-        of tyRange: "range"
-        of tyDistinct: "distinct"
-        of tyProc: "proc"
-        of tyObject: "object"
-        of tyTuple: "tuple"
-        of tyOpenArray: "openArray"
-        else: typeToStr[t.base.kind]
-    of tyInferred:
-      let concrete = t.previouslyInferred
-      if concrete != nil: result = typeToString(concrete)
-      else: result = "inferred[" & typeToString(t.base) & "]"
-    of tyUserTypeClassInst:
-      let body = t.base
-      result = body.sym.name.s & "["
-      for needsComma, a in t.userTypeClassInstParams:
-        if needsComma: result.add(", ")
-        result.add(typeToString(a))
-      result.add "]"
-    of tyAnd:
-      for i, son in t.ikids:
-        if i > 0: result.add(" and ")
-        result.add(typeToString(son))
-    of tyOr:
-      for i, son in t.ikids:
-        if i > 0: result.add(" or ")
-        result.add(typeToString(son))
-    of tyNot:
-      result = "not " & typeToString(t.elementType)
-    of tyUntyped:
-      #internalAssert t.len == 0
-      result = "untyped"
-    of tyFromExpr:
-      if t.n == nil:
-        result = "unknown"
-      else:
-        result = "typeof(" & renderTree(t.n) & ")"
-    of tyArray:
-      result = "array"
-      if t.hasElementType:
-        if t.indexType.kind == tyRange:
-          result &= "[" & rangeToStr(t.indexType.n) & ", " &
-              typeToString(t.elementType) & ']'
-        else:
-          result &= "[" & typeToString(t.indexType) & ", " &
-              typeToString(t.elementType) & ']'
-    of tyUncheckedArray:
-      result = "UncheckedArray"
-      if t.hasElementType:
-        result &= "[" & typeToString(t.elementType) & ']'
-    of tySequence:
-      if t.sym != nil and prefer != preferResolved:
-        result = t.sym.name.s
-      else:
-        result = "seq"
-        if t.hasElementType:
-          result &= "[" & typeToString(t.elementType) & ']'
-    of tyOrdinal:
-      result = "ordinal"
-      if t.hasElementType:
-        result &= "[" & typeToString(t.skipModifier) & ']'
-    of tySet:
-      result = "set"
-      if t.hasElementType:
-        result &= "[" & typeToString(t.elementType) & ']'
-    of tyOpenArray:
-      result = "openArray"
-      if t.hasElementType:
-        result &= "[" & typeToString(t.elementType) & ']'
-    of tyDistinct:
-      result = "distinct " & typeToString(t.elementType,
-        if prefer == preferModuleInfo: preferModuleInfo else: preferTypeName)
-    of tyIterable:
-      # xxx factor this pattern
-      result = "iterable"
-      if t.hasElementType:
-        result &= "[" & typeToString(t.skipModifier) & ']'
-    of tyTuple:
-      # we iterate over t.sons here, because t.n may be nil
-      if t.n != nil:
-        result = "tuple["
-        for i in 0..<t.n.len:
-          assert(t.n[i].kind == nkSym)
-          result.add(t.n[i].sym.name.s & ": " & typeToString(t.n[i].sym.typ))
-          if i < t.n.len - 1: result.add(", ")
-        result.add(']')
-      elif t.isEmptyTupleType:
-        result = "tuple[]"
-      elif t.isSingletonTupleType:
-        result = "("
-        for son in t.kids:
-          result.add(typeToString(son))
-        result.add(",)")
-      else:
-        result = "("
-        for i, son in t.ikids:
-          if i > 0: result.add ", "
-          result.add(typeToString(son))
-        result.add(')')
-    of tyPtr, tyRef, tyVar, tyLent:
-      result = if isOutParam(t): "out " else: typeToStr[t.kind]
-      result.add typeToString(t.elementType)
-    of tyRange:
-      result = "range "
-      if t.n != nil and t.n.kind == nkRange:
-        result.add rangeToStr(t.n)
-      if prefer != preferExported:
-        result.add("(" & typeToString(t.elementType) & ")")
-    of tyProc:
-      result = if tfIterator in t.flags: "iterator "
-               elif t.owner != nil:
-                 case t.owner.kind
-                 of skTemplate: "template "
-                 of skMacro: "macro "
-                 of skConverter: "converter "
-                 else: "proc "
-              else:
-                "proc "
-      if tfUnresolved in t.flags: result.add "[*missing parameters*]"
-      result.add "("
-      for i, a in t.paramTypes:
-        if i > FirstParamAt: result.add(", ")
-        let j = paramTypeToNodeIndex(i)
-        if t.n != nil and j < t.n.len and t.n[j].kind == nkSym:
-          result.add(t.n[j].sym.name.s)
-          result.add(": ")
-        result.add(typeToString(a))
-      result.add(')')
-      if t.returnType != nil: result.add(": " & typeToString(t.returnType))
-      var prag = if t.callConv == ccNimCall and tfExplicitCallConv notin t.flags: "" else: $t.callConv
-      var hasImplicitRaises = false
-      if not isNil(t.owner) and not isNil(t.owner.ast) and (t.owner.ast.len - 1) >= pragmasPos:
-        let pragmasNode = t.owner.ast[pragmasPos]
-        let raisesSpec = effectSpec(pragmasNode, wRaises)
-        if not isNil(raisesSpec):
-          addSep(prag)
-          prag.add("raises: ")
-          prag.add(renderTree raisesSpec)
-          hasImplicitRaises = true
-      if tfNoSideEffect in t.flags:
-        addSep(prag)
-        prag.add("noSideEffect")
-      if tfThread in t.flags:
-        addSep(prag)
-        prag.add("gcsafe")
-      var effectsOfStr = ""
-      for i, a in t.paramTypes:
-        let j = paramTypeToNodeIndex(i)
-        if t.n != nil and j < t.n.len and t.n[j].kind == nkSym and t.n[j].sym.kind == skParam and sfEffectsDelayed in t.n[j].sym.flags:
-          addSep(effectsOfStr)
-          effectsOfStr.add(t.n[j].sym.name.s)
-      if effectsOfStr != "":
-        addSep(prag)
-        prag.add("effectsOf: ")
-        prag.add(effectsOfStr)
-      if not hasImplicitRaises and prefer == preferInferredEffects and not isNil(t.owner) and not isNil(t.owner.typ) and not isNil(t.owner.typ.n) and (t.owner.typ.n.len > 0):
-        let effects = t.n[0]
-        if effects.kind == nkEffectList and effects.len == effectListLen:
-          var inferredRaisesStr = ""
-          let effs = effects[exceptionEffects]
-          if not isNil(effs):
-            for eff in items(effs):
-              if not isNil(eff):
-                addSep(inferredRaisesStr)
-                inferredRaisesStr.add($eff.typ)
-          addSep(prag)
-          prag.add("raises: <inferred> [")
-          prag.add(inferredRaisesStr)
-          prag.add("]")
-      if prag.len != 0: result.add("{." & prag & ".}")
-    of tyVarargs:
-      result = typeToStr[t.kind] % typeToString(t.elementType)
-    of tySink:
-      result = "sink " & typeToString(t.skipModifier)
-    of tyOwned:
-      result = "owned " & typeToString(t.elementType)
-    else:
-      result = typeToStr[t.kind]
-    result.addTypeFlags(t)
-  result = typeToString(typ, prefer)
-
-
 proc disamb(g: var TSrcGen; s: PSym): int =
   # we group by 's.name.s' to compute the stable name ID.
   result = 0
@@ -582,7 +229,6 @@ proc put(g: var TSrcGen, kind: TokType, s: string; sym: PSym = nil) =
   inc(g.lineLen, s.len)
 
 proc putComment(g: var TSrcGen, s: string) =
-  const SpecialWhitespace = {' ', '\t', '\r', '\n', '\0'}
   if s.len == 0: return
   var i = 0
   let hi = s.len - 1
@@ -612,12 +258,12 @@ proc putComment(g: var TSrcGen, s: string) =
       # gets too long:
       # compute length of the following word:
       var j = i
-      while j <= hi and s[j] notin SpecialWhitespace: inc(j)
+      while j <= hi and s[j] > ' ': inc(j)
       if not isCode and (g.col + (j - i) > MaxLineLen):
         put(g, tkComment, com)
         optNL(g, ind)
         com = "## "
-      while i <= hi and s[i] notin SpecialWhitespace:
+      while i <= hi and s[i] > ' ':
         com.add(s[i])
         inc(i)
   put(g, tkComment, com)
@@ -1216,28 +862,10 @@ proc genSymSuffix(result: var string, s: PSym) {.inline.} =
     result.add '_'
     result.addInt s.id
 
-proc gsemmedParams(g: var TSrcGen, n: PNode) =
-  put(g, tkParLe, "(")
-  for i in 1..<n.len:
-    if i > 1:
-      putWithSpace(g, tkComma, ";")
-    let x {.cursor.} = n[i]
-    if x.kind == nkSym:
-      put g, tkSymbol, renderDefinitionName(x.sym)
-      putWithSpace(g, tkColon, ":")
-      put g, tkSymbol, typeToString(x.sym.typ)
-    else:
-      gsub(g, x)
-  put(g, tkParRi, ")")
-  if not isEmptyType(n[0].typ):
-    putWithSpace(g, tkColon, ":")
-    gsub(g, n[0])
-
 proc gproc(g: var TSrcGen, n: PNode) =
   var c: TContext = initContext()
-  var s: PSym = nil
   if n[namePos].kind == nkSym:
-    s = n[namePos].sym
+    let s = n[namePos].sym
     var ret = renderDefinitionName(s)
     ret.genSymSuffix(s)
     put(g, tkSymbol, ret)
@@ -1252,10 +880,7 @@ proc gproc(g: var TSrcGen, n: PNode) =
       gsub(g, n[miscPos][1])
     else:
       gsub(g, n[genericParamsPos])
-  if n[paramsPos].len == 0 and s != nil and s.typ != nil and s.typ.n != nil:
-    gsemmedParams(g, s.typ.n)
-  else:
-    gsub(g, n[paramsPos])
+  gsub(g, n[paramsPos])
   if renderNoPragmas notin g.flags:
     gsub(g, n[pragmasPos])
   if renderNoBody notin g.flags:

compiler/scriptconfig.nim

@@ -231,7 +231,7 @@ proc runNimScript*(cache: IdentCache; scriptName: AbsoluteFile;
   if optOwnedRefs in oldGlobalOptions:
     conf.globalOptions.incl {optTinyRtti, optOwnedRefs, optSeqDestructors}
     defineSymbol(conf.symbols, "nimv2")
-  if conf.selectedGC in {gcArc, gcOrc, gcYrc, gcAtomicArc}:
+  if conf.selectedGC in {gcArc, gcOrc, gcAtomicArc}:
     conf.globalOptions.incl {optTinyRtti, optSeqDestructors}
     defineSymbol(conf.symbols, "nimv2")
     defineSymbol(conf.symbols, "gcdestructors")
@@ -241,8 +241,6 @@ proc runNimScript*(cache: IdentCache; scriptName: AbsoluteFile;
       defineSymbol(conf.symbols, "gcarc")
     of gcOrc:
       defineSymbol(conf.symbols, "gcorc")
-    of gcYrc:
-      defineSymbol(conf.symbols, "gcyrc")
     of gcAtomicArc:
       defineSymbol(conf.symbols, "gcatomicarc")
     else:

compiler/sem.nim

@@ -105,12 +105,9 @@ proc fitNode(c: PContext, formal: PType, arg: PNode; info: TLineInfo): PNode =
     result.typ = formal
   elif arg.kind in nkSymChoices and formal.skipTypes(abstractInst).kind == tyEnum:
     # Pick the right 'sym' from the sym choice by looking at 'formal' type:
-    # The choice candidates may be wrapped in `var`/`lent` when they come from
-    # a loop-local view, but for enum disambiguation only the underlying enum
-    # type matters.
     result = nil
     for ch in arg:
-      if sameType(ch.typ.skipTypes({tyVar, tyLent}), formal):
+      if sameType(ch.typ, formal):
         return ch
     typeMismatch(c.config, info, formal, arg.typ, arg)
   else:
@@ -250,26 +247,6 @@ proc newSymG*(kind: TSymKind, n: PNode, c: PContext): PSym =
     if result.kind notin {kind, skTemp}:
       localError(c.config, n.info, "cannot use symbol of kind '$1' as a '$2'" %
         [result.kind.toHumanStr, kind.toHumanStr])
-    # bug #25693: a local declared inside a template/macro operand (recorded in
-    # `shadowDiscardedDefs`) can be captured by a `{.dirty.}` template and
-    # re-emitted as a definition more than once. The first emission keeps the
-    # original symbol (so a leaked dirty-template name still resolves); every
-    # later emission gets a fresh copy, so distinct emissions don't share one
-    # symbol - which the destructor/liveness analysis would otherwise miscompile.
-    # Unlike a plain redefinition check this is control-flow agnostic, so the
-    # common "emit a `typed` body in several mutually-exclusive branches" pattern
-    # keeps working. gensym'ed locals (and ones derived from a gensym name) are
-    # excluded: the gensym machinery already keeps their names unique, and a
-    # fresh copy would reuse the unique name and clash in the same scope.
-    if kind in {skVar, skLet, skForVar} and
-        {sfGenSym, sfWasGenSym} * result.flags == {} and
-        result.id in c.shadowDiscardedDefs:
-      if containsOrIncl(c.realizedDefs, result.id):
-        let fresh = copySym(result, c.idgen)
-        fresh.ast = result.ast
-        put(c.p, result, fresh)
-        c.hasSymRedefs = true
-        result = fresh
     when false:
       if sfGenSym in result.flags and result.kind notin {skTemplate, skMacro, skParam}:
         # declarative context, so produce a fresh gensym:
@@ -878,7 +855,7 @@ proc semStmtAndGenerateGenerics(c: PContext, n: PNode): PNode =
     appendToModule(c.module, result)
   trackStmt(c, c.module, result, isTopLevel = true)
   if optMultiMethods notin c.config.globalOptions and
-      c.config.selectedGC in {gcArc, gcOrc, gcAtomicArc, gcYrc} and
+      c.config.selectedGC in {gcArc, gcOrc, gcAtomicArc} and
       Feature.vtables in c.config.features:
     sortVTableDispatchers(c.graph)
 
@@ -912,6 +889,8 @@ proc semWithPContext*(c: PContext, n: PNode): PNode =
       else:
         result = newNodeI(nkEmpty, n.info)
       #if c.config.cmd == cmdIdeTools: findSuggest(c, n)
+  storeRodNode(c, result)
+
 
 proc reportUnusedModules(c: PContext) =
   if c.config.cmd == cmdM: return

compiler/semcall.nim

@@ -90,14 +90,8 @@ proc addTypeBoundSymbols(graph: ModuleGraph, arg: PType, name: PIdent,
     # argument must be typed first, meaning arguments always
     # matching `untyped` are ignored
     let t = nominalRoot(arg)
-    if t != nil and t.owner.kind == skModule and
-        t.owner.position >= 0 and t.owner.position < graph.ifaces.len:
-      # search module for routines attachable to `t`.
-      # Under IC the nominal type may have been loaded from a NIF file, in which
-      # case its owner module is a stub whose `position` (a NIF-suffix file index)
-      # has no `ifaces` slot; such type-bound ops are reachable through normal
-      # imports instead, so skip the direct module scan to avoid an out-of-range
-      # access.
+    if t != nil and t.owner.kind == skModule:
+      # search module for routines attachable to `t`
       let module = t.owner
       var iter = default(ModuleIter)
       var s = initModuleIter(iter, graph, module, name)
@@ -137,7 +131,7 @@ proc pickBestCandidate(c: PContext, headSymbol: PNode,
   var sym = syms[0].s
   let name = sym.name
   var scope = syms[0].scope
-  c.openShadowScope
+
   if allowTypeBoundOps:
     for a in 1 ..< n.len:
       # for every already typed argument, add type bound ops
@@ -166,13 +160,9 @@ proc pickBestCandidate(c: PContext, headSymbol: PNode,
           addTypeBoundSymbols(c.graph, arg.typ, name, filter, symMarker, syms)
 
       if z.state == csMatch:
-        # Iterator preference is heuristic in iterator-admitting contexts.
-        # The dedicated iterable path uses `iteratorPreference`, other
-        # context use exact-match bump
+        # little hack so that iterators are preferred over everything else:
         if sym.kind == skIterator:
-          if efPreferIteratorForIterable in flags:
-            inc(z.iteratorPreference)
-          elif not (efWantIterator notin flags and efWantIterable in flags):
+          if not (efWantIterator notin flags and efWantIterable in flags):
             inc(z.exactMatches, 200)
           else:
             dec(z.exactMatches, 200)
@@ -224,10 +214,6 @@ proc pickBestCandidate(c: PContext, headSymbol: PNode,
     scope = syms[nextSymIndex].scope
     inc(nextSymIndex)
 
-  if best.state == csMatch and best.calleeSym != nil and best.calleeSym.kind in {skTemplate, skMacro}:
-    c.closeShadowScope
-  else:
-    c.mergeShadowScope
 
 proc effectProblem(f, a: PType; result: var string; c: PContext) =
   if f.kind == tyProc and a.kind == tyProc:
@@ -685,7 +671,7 @@ proc bracketNotFoundError(c: PContext; n: PNode; flags: TExprFlags) =
   # copied from semOverloadedCallAnalyzeEffects, might be overkill:
   const baseFilter = {skProc, skFunc, skMethod, skConverter, skMacro, skTemplate}
   let filter =
-    if flags*{efInTypeof, efWantIterator, efWantIterable, efPreferIteratorForIterable} != {}:
+    if flags*{efInTypeof, efWantIterator, efWantIterable} != {}:
       baseFilter + {skIterator}
     else: baseFilter
   # this will add the errors:
@@ -732,15 +718,6 @@ proc indexTypesMatch(c: PContext, f, a: PType, arg: PNode): PNode =
   result = paramTypesMatch(m, f, a, arg, nil)
   if m.genericConverter and result != nil:
     instGenericConvertersArg(c, result, m)
-  when defined(icDbg):
-    if result == nil and f != nil and a != nil and f.kind == tyEnum:
-      echo "INDEXMISMATCH f=", typeToString(f), " itemId=", f.itemId,
-        " uniqueId=", f.uniqueId, " mod=", toFullPath(c.config, f.itemId.module.FileIndex),
-        " sym=", (if f.sym != nil: $f.sym.itemId else: "nil"), " state=", f.state
-      let a2 = a.skipTypes({tyRange})
-      echo "  a=", typeToString(a), " itemId=", a2.itemId, " uniqueId=", a2.uniqueId,
-        " mod=", toFullPath(c.config, a2.itemId.module.FileIndex),
-        " sym=", (if a2.sym != nil: $a2.sym.itemId else: "nil"), " state=", a2.state
 
 proc inferWithMetatype(c: PContext, formal: PType,
                        arg: PNode, coerceDistincts = false): PNode =
@@ -853,21 +830,6 @@ proc inheritBindings(c: PContext, x: var TCandidate, expectedType: PType) =
   for i in 0 ..< flatUnbound.len():
     x.bindings.put(flatUnbound[i], flatBound[i])
 
-proc compactVoidArgs(n: PNode): PNode =
-  # deletes void args from the argument list, which are created by `setSon`
-  var hasNil = false
-  for i in 0..<n.len:
-    if n[i] == nil:
-      hasNil = true
-      break
-  if not hasNil:
-    result = n
-  else:
-    result = copyNode(n)
-    for i in 0..<n.len:
-      if n[i] != nil:
-        result.add n[i]
-
 proc semResolvedCall(c: PContext, x: var TCandidate,
                      n: PNode, flags: TExprFlags;
                      expectedType: PType = nil): PNode =
@@ -918,7 +880,7 @@ proc semResolvedCall(c: PContext, x: var TCandidate,
   markUsed(c, info, finalCallee, isGenericInstance = true)
   onUse(info, finalCallee, isGenericInstance = true)
 
-  result = compactVoidArgs(x.call)
+  result = x.call
   instGenericConvertersSons(c, result, x)
   markConvertersUsed(c, result)
   result[0] = newSymNode(finalCallee, getCallLineInfo(result[0]))
@@ -983,12 +945,7 @@ proc explicitGenericSym(c: PContext, n: PNode, s: PSym, errors: var CandidateErr
         diagnostics: m.diagnostics))
     return nil
   var newInst = generateInstance(c, s, m.bindings, n.info)
-  # `generateInstance` may return an instance REUSED from another module's NIF
-  # `(offer …)` — its type is Sealed (immutable). Such an instance is already
-  # fully resolved (`tfUnresolved` cleared at its original instantiation), so the
-  # `excl` is a no-op; skip it rather than assert on a Sealed-type mutation.
-  if newInst.typ.state != Sealed:
-    newInst.typ.excl tfUnresolved
+  newInst.typ.excl tfUnresolved
   let info = getCallLineInfo(n)
   markUsed(c, info, s, isGenericInstance = false)
   onUse(info, s, isGenericInstance = false)
@@ -1009,7 +966,7 @@ proc setGenericParams(c: PContext, n, expectedParams: PNode) =
     if e.typ == nil:
       n[i].typ = errorType(c)
     else:
-      n[i].typ = e.typ
+      n[i].typ = e.typ.skipTypes({tyTypeDesc})
 
 proc explicitGenericInstantiation(c: PContext, n: PNode, s: PSym, doError: bool): PNode =
   assert n.kind == nkBracketExpr

compiler/semdata.nim

@@ -19,6 +19,8 @@ import
   magicsys, vmdef, modulegraphs, lineinfos, pathutils, layeredtable,
   types, lowerings, trees, parampatterns, astalgo
 
+import ic / ic
+
 type
   TOptionEntry* = object      # entries to put on a stack for pragma parsing
     options*: TOptions
@@ -54,18 +56,7 @@ type
     inst*: PInstantiation
 
   TExprFlag* = enum
-    efLValue,
-      # The expression is used as an assignable location.
-    efWantIterator,
-      # Admit iterator candidates and prefer them during overload resolution.
-    efWantIterable,
-      # Admit iterator candidates for expressions that may feed iterable-style
-      # chaining.
-    efPreferIteratorForIterable,
-      # Prefer iterator candidates for `iterable[T]` matching and wrap a
-      # successful iterator call as `tyIterable`.
-    efInTypeof,
-      # The expression is being semchecked under `typeof`.
+    efLValue, efWantIterator, efWantIterable, efInTypeof,
     efNeedStatic,
       # Use this in contexts where a static value is mandatory
     efPreferStatic,
@@ -180,27 +171,12 @@ type
     sideEffects*: Table[int, seq[(TLineInfo, PSym)]] # symbol.id index
     inUncheckedAssignSection*: int
     importModuleLookup*: Table[int, seq[int]] # (module.ident.id, [module.id])
-    forwardTypeUpdates*: seq[(PSym, PType, PNode)]
-      # top-level owner, type, and type node for delayed retries inside a
-      # type section due to containing forward types
-    forwardFieldUpdates*: seq[(PType, PNode, PType)]
-      # object/tuple field definitions whose default values mention forward
-      # types and need delayed const checking
+    forwardTypeUpdates*: seq[(PType, PNode)]
+      # types that need to be updated in a type section
+      # due to containing forward types, and their corresponding nodes
     inTypeofContext*: int
 
     semAsgnOpr*: proc (c: PContext; n: PNode; k: TNodeKind): PNode {.nimcall.}
-    shadowDiscardedDefs*: IntSet
-      # ids of local symbols that were declared inside a template/macro operand's
-      # shadow scope and then discarded; re-emitting such a symbol as a
-      # definition gives a fresh copy so distinct emissions don't share a symbol.
-      # See bug #25693 and `rememberShadowDefs`.
-    realizedDefs*: IntSet
-      # ids from `shadowDiscardedDefs` already realized once; the first emission
-      # keeps the original symbol (so leaked dirty-template names still resolve),
-      # later emissions get a fresh copy.
-    hasSymRedefs*: bool
-      # set once a redefinition mapping has been installed; makes `getGenSym`
-      # consult the proc-con mapping for non-gensym symbols too.
 
   TBorrowState* = enum
     bsNone, bsReturnNotMatch, bsNoDistinct, bsGeneric, bsNotSupported, bsMatch
@@ -293,10 +269,7 @@ proc get*(p: PProcCon; key: PSym): PSym =
   result = p.mapping.getOrDefault(key.itemId)
 
 proc getGenSym*(c: PContext; s: PSym): PSym =
-  # `c.hasSymRedefs` additionally routes ordinary (non-gensym) symbols through
-  # the mapping so a re-emitted definition can redirect them to its fresh copy,
-  # see bug #25693 and `newSymG`.
-  if sfGenSym notin s.flags and not c.hasSymRedefs: return s
+  if sfGenSym notin s.flags: return s
   var it = c.p
   while it != nil:
     result = get(it, s)
@@ -358,30 +331,33 @@ proc newContext*(graph: ModuleGraph; module: PSym): PContext =
     userPragmas: initStrTable(),
     generics: @[],
     unknownIdents: initIntSet(),
-    shadowDiscardedDefs: initIntSet(),
-    realizedDefs: initIntSet(),
     cache: graph.cache,
     graph: graph,
     signatures: initStrTable(),
     features: graph.config.features
   )
+  if graph.config.symbolFiles != disabledSf:
+    let id = module.position
+    if graph.config.cmd != cmdM:
+      assert graph.packed[id].status in {undefined, outdated}
+    graph.packed[id].status = storing
+    graph.packed[id].module = module
+    initEncoder graph, module
+
+template packedRepr*(c): untyped = c.graph.packed[c.module.position].fromDisk
+template encoder*(c): untyped = c.graph.encoders[c.module.position]
 
 proc addIncludeFileDep*(c: PContext; f: FileIndex) =
-  discard
+  if c.config.symbolFiles != disabledSf:
+    addIncludeFileDep(c.encoder, c.packedRepr, f)
 
 proc addImportFileDep*(c: PContext; f: FileIndex) =
-  # Under `nim m` (the IC frontend) record the REAL direct imports of the
-  # current module as sem resolves them — including imports a macro generated
-  # (e.g. chronicles' `parseStmt("import chronicles/textlines")`), which the
-  # static dependency scanner never sees. `nim ic` writes this set as the
-  # module's `.s.deps` sidecar and re-derives the build graph from it, so the
-  # discovery is structured data instead of a build-failure side channel.
-  if c.config.cmd == cmdM:
-    let importer = c.module.position.FileIndex
-    var deps = addr c.graph.importDeps.mgetOrPut(importer, @[])
-    if f notin deps[]: deps[].add f
+  if c.config.symbolFiles != disabledSf:
+    addImportFileDep(c.encoder, c.packedRepr, f)
 
 proc addPragmaComputation*(c: PContext; n: PNode) =
+  if c.config.symbolFiles != disabledSf:
+    addPragmaComputation(c.encoder, c.packedRepr, n)
   # Also store for NIF-based IC (cmdM mode or optCompress)
   if optCompress in c.config.globalOptions or c.config.cmd == cmdM:
     addNifReplayAction(c.graph, c.module.position.int32, n)
@@ -392,47 +368,38 @@ proc inclSym(sq: var seq[PSym], s: PSym): bool =
   sq.add s
   result = true
 
-proc addConverter*(c: PContext, conv: PSym) =
-  assert conv != nil
-  if inclSym(c.converters, conv):
+proc addConverter*(c: PContext, conv: LazySym) =
+  assert conv.sym != nil
+  if inclSym(c.converters, conv.sym):
     add(c.graph.ifaces[c.module.position].converters, conv)
-    # Record for IC: the loader rebuilds Iface.converters from the NIF's
-    # (repconverter ...) entries (moduleFromNifFile). This must capture not only
-    # converters DEFINED in this module (addConverterDef) but also ones IMPORTED
-    # from another module here (importer.addUnnamedIt re-adds a re-exported
-    # module's converters via this proc). Otherwise a loaded module's
-    # re-exported converters were invisible to importers and implicit
-    # conversions silently stopped matching at a consumer that reaches the
-    # converter only through this module's re-export chain (e.g. faststreams'
-    # `InputStreamHandle -> InputStream` via ssz_serialization, breaking
-    # `SSZ.decode`/`encode`). `inclSym` guards against duplicate log entries.
-    c.graph.opsLog.add LogEntry(kind: ConverterEntry, module: c.module.position,
-                                key: "", sym: conv)
 
-proc addConverterDef*(c: PContext, conv: PSym) =
+proc addConverterDef*(c: PContext, conv: LazySym) =
   addConverter(c, conv)
+  if c.config.symbolFiles != disabledSf:
+    addConverter(c.encoder, c.packedRepr, conv.sym)
 
-proc addPureEnum*(c: PContext, e: PSym) =
-  assert e != nil
+proc addPureEnum*(c: PContext, e: LazySym) =
+  assert e.sym != nil
   add(c.graph.ifaces[c.module.position].pureEnums, e)
-  # record for IC: a NIF-loaded module rebuilds `Iface.pureEnums` from these log
-  # entries (moduleFromNifFile); without it a loaded module's pure enums were
-  # invisible to importers, so `importPureEnumFields` never offered their fields
-  # and unqualified pure-enum values stopped resolving. (Same pattern as
-  # `addConverterDef`.)
-  c.graph.opsLog.add LogEntry(kind: PureEnumEntry, module: c.module.position,
-                              key: "", sym: e)
+  if c.config.symbolFiles != disabledSf:
+    addPureEnum(c.encoder, c.packedRepr, e.sym)
 
-proc addPattern*(c: PContext, p: PSym) =
-  assert p != nil
-  if inclSym(c.patterns, p):
+proc addPattern*(c: PContext, p: LazySym) =
+  assert p.sym != nil
+  if inclSym(c.patterns, p.sym):
     add(c.graph.ifaces[c.module.position].patterns, p)
+  if c.config.symbolFiles != disabledSf:
+    addTrmacro(c.encoder, c.packedRepr, p.sym)
 
 proc exportSym*(c: PContext; s: PSym) =
   strTableAdds(c.graph, c.module, s)
+  if c.config.symbolFiles != disabledSf:
+    addExported(c.encoder, c.packedRepr, s)
 
 proc reexportSym*(c: PContext; s: PSym) =
   strTableAdds(c.graph, c.module, s)
+  if c.config.symbolFiles != disabledSf:
+    addReexport(c.encoder, c.packedRepr, s)
 
 proc newLib*(kind: TLibKind): PLib =
   result = PLib(kind: kind)   #result.syms = initObjectSet()
@@ -647,11 +614,19 @@ template addExport*(c: PContext; s: PSym) =
   ## convenience to export a symbol from the current module
   addExport(c.graph, c.module, s)
 
+proc storeRodNode*(c: PContext, n: PNode) =
+  if c.config.symbolFiles != disabledSf:
+    toPackedNodeTopLevel(n, c.encoder, c.packedRepr)
+
 proc addToGenericProcCache*(c: PContext; s: PSym; inst: PInstantiation) =
-  c.graph.procInstCache.mgetOrPut(s.itemId, @[]).add inst
+  c.graph.procInstCache.mgetOrPut(s.itemId, @[]).add LazyInstantiation(module: c.module.position, inst: inst)
+  if c.config.symbolFiles != disabledSf:
+    storeInstantiation(c.encoder, c.packedRepr, s, inst)
 
 proc addToGenericCache*(c: PContext; s: PSym; inst: PType) =
-  c.graph.typeInstCache.mgetOrPut(s.itemId, @[]).add inst
+  c.graph.typeInstCache.mgetOrPut(s.itemId, @[]).add LazyType(typ: inst)
+  if c.config.symbolFiles != disabledSf:
+    storeTypeInst(c.encoder, c.packedRepr, s, inst)
 
 proc sealRodFile*(c: PContext) =
   if c.config.symbolFiles != disabledSf:
@@ -667,8 +642,9 @@ proc rememberExpansion*(c: PContext; info: TLineInfo; expandedSym: PSym) =
   ## in the sem'checked AST. This is very bad for IDE-like tooling
   ## ("find all usages of this template" would not work). We need special
   ## logic to remember macro/template expansions. This is done here and
-  ## delegated to the "NIF" file mechanism.
-  discard "XXX To implement"
+  ## delegated to the "rod" file mechanism.
+  if c.config.symbolFiles != disabledSf:
+    storeExpansion(c.encoder, c.packedRepr, info, expandedSym)
 
 const
   errVarForOutParamNeededX = "for a 'var' type a variable needs to be passed; but '$1' is immutable"
@@ -682,11 +658,6 @@ proc renderNotLValue*(n: PNode): string =
   elif n.kind in {nkHiddenStdConv, nkHiddenSubConv} and n.len == 2:
     result = typeToString(n.typ.skipTypes(abstractVar)) & "(" & result & ")"
 
-proc isSsoStringIndex*(conf: ConfigRef; n: PNode): bool =
-  result = conf.usesSso() and n.kind == nkBracketExpr and n.len >= 1 and
-      n[0].typ != nil and
-      n[0].typ.skipTypes(abstractVar + abstractInst - {tyTypeDesc}).kind == tyString
-
 proc isAssignable(c: PContext, n: PNode): TAssignableResult =
   result = parampatterns.isAssignable(c.p.owner, n)
 
@@ -794,7 +765,7 @@ proc replaceHookMagic*(c: PContext, n: PNode, kind: TTypeAttachedOp): PNode =
   case kind
   of attachedDestructor:
     result = n
-    let t = n[1].typ.skipTypes({tyAlias, tyVar, tySink})
+    let t = n[1].typ.skipTypes(abstractVar)
     let op = getAttachedOp(c.graph, t, attachedDestructor)
     if op != nil:
       result[0] = newSymNode(op)
@@ -806,13 +777,13 @@ proc replaceHookMagic*(c: PContext, n: PNode, kind: TTypeAttachedOp): PNode =
           result[1] = skipAddr(n[1])
   of attachedTrace:
     result = n
-    let t = n[1].typ.skipTypes({tyAlias, tyVar, tySink})
+    let t = n[1].typ.skipTypes(abstractVar)
     let op = getAttachedOp(c.graph, t, attachedTrace)
     if op != nil:
       result[0] = newSymNode(op)
   of attachedDup:
     result = n
-    let t = n[1].typ.skipTypes({tyAlias, tyVar, tySink})
+    let t = n[1].typ.skipTypes(abstractVar)
     let op = getAttachedOp(c.graph, t, attachedDup)
     if op != nil:
       result[0] = newSymNode(op)
@@ -822,26 +793,18 @@ proc replaceHookMagic*(c: PContext, n: PNode, kind: TTypeAttachedOp): PNode =
         result.add boolLit
   of attachedWasMoved:
     result = n
-    let t = n[1].typ.skipTypes({tyAlias, tyVar, tySink})
+    let t = n[1].typ.skipTypes(abstractVar)
     let op = getAttachedOp(c.graph, t, attachedWasMoved)
     if op != nil:
       result[0] = newSymNode(op)
       analyseIfAddressTakenInCall(c, result, false)
   of attachedSink:
-    result = n
-    let t = n[1].typ.skipTypes({tyAlias, tyVar, tySink})
-    let op = getAttachedOp(c.graph, t, kind)
-    if op != nil:
-      result[0] = newSymNode(op)
+    result = c.semAsgnOpr(c, n, nkSinkAsgn)
   of attachedAsgn:
-    result = n
-    let t = n[1].typ.skipTypes({tyAlias, tyVar, tySink})
-    let op = getAttachedOp(c.graph, t, kind)
-    if op != nil:
-      result[0] = newSymNode(op)
+    result = c.semAsgnOpr(c, n, nkAsgn)
   of attachedDeepCopy:
     result = n
-    let t = n[1].typ.skipTypes({tyAlias, tyVar, tySink})
+    let t = n[1].typ.skipTypes(abstractVar)
     let op = getAttachedOp(c.graph, t, kind)
     if op != nil:
       result[0] = newSymNode(op)

compiler/semexprs.nim

@@ -27,11 +27,6 @@ const
 proc semTemplateExpr(c: PContext, n: PNode, s: PSym,
                      flags: TExprFlags = {}; expectedType: PType = nil): PNode =
   rememberExpansion(c, n.info, s)
-  # IC: this expands `s`'s body into the current module's sem, so the module
-  # depends on that body — record a NeedsImpl (strong) edge to `s`'s module.
-  # The iface cookie hashes only signatures now, so a template body edit moves
-  # only the impl cookie, and just the modules that expanded it re-sem.
-  recordIcImplDep(c.graph, s)
   let info = getCallLineInfo(n)
   markUsed(c, info, s)
   onUse(info, s)
@@ -62,16 +57,6 @@ proc semOperand(c: PContext, n: PNode, flags: TExprFlags = {}): PNode =
   elif {efWantStmt, efAllowStmt} * flags != {}:
     result.typ = newTypeS(tyVoid, c)
   else:
-    when defined(icDbgRefc):
-      echo "[icNoType] semOperand: ", renderTree(result, {renderNoComments}),
-        " kind=", result.kind,
-        (if result.kind in {nkCall, nkCommand} and result[0].kind == nkSym:
-          " calleeTyp=" & (if result[0].sym.typ == nil: "NIL" else:
-            $result[0].sym.typ.kind & " ret=" &
-            (if result[0].sym.typ.returnType == nil: "NIL"
-             else: $result[0].sym.typ.returnType.kind))
-         else: "")
-      echo getStackTrace()
     localError(c.config, n.info, errExprXHasNoType %
                renderTree(result, {renderNoComments}))
     result.typ = errorType(c)
@@ -98,17 +83,6 @@ proc semExprWithType(c: PContext, n: PNode, flags: TExprFlags = {}, expectedType
   if result.typ == nil and efInTypeof in flags:
     result.typ = c.voidType
   elif result.typ == nil or result.typ == c.enforceVoidContext:
-    when defined(icDbgRefc):
-      echo "[icNoType] semExprWithType: ", renderTree(result, {renderNoComments}),
-        " kind=", result.kind,
-        (if result.kind in {nkCall, nkCommand} and result[0].kind == nkSym:
-          " callee=" & result[0].sym.name.s &
-          " calleeTyp=" & (if result[0].sym.typ == nil: "NIL" else:
-            $result[0].sym.typ.kind & " ret=" &
-            (if result[0].sym.typ.returnType == nil: "NIL"
-             else: $result[0].sym.typ.returnType.kind))
-         else: "")
-      echo getStackTrace()
     localError(c.config, n.info, errExprXHasNoType %
                 renderTree(result, {renderNoComments}))
     result.typ = errorType(c)
@@ -132,9 +106,7 @@ proc semExprWithType(c: PContext, n: PNode, flags: TExprFlags = {}, expectedType
 
 proc semExprNoDeref(c: PContext, n: PNode, flags: TExprFlags = {}): PNode =
   result = semExprCheck(c, n, flags)
-  if result.typ == nil and efInTypeof in flags:
-    result.typ = c.voidType
-  elif result.typ == nil:
+  if result.typ == nil:
     localError(c.config, n.info, errExprXHasNoType %
                renderTree(result, {renderNoComments}))
     result.typ = errorType(c)
@@ -225,29 +197,6 @@ proc semOpenSym(c: PContext, n: PNode, flags: TExprFlags, expectedType: PType,
       # set symchoice node type back to None
       n.typ = newTypeS(tyNone, c)
 
-proc resolveOpenSymDotRhs(c: PContext, n: PNode): PNode =
-  ## Resolves an `nkOpenSym` in the field position of a dot expression.
-  ## The dot handling (`builtinFieldAccess`, `dotTransformation`) matches on
-  ## the node kind of the RHS directly, so the wrapper cannot be left for
-  ## `semExpr` to unwrap; without this the captured symbol degrades to a
-  ## plain identifier that is then only looked up in the instantiation
-  ## context. Mirrors `semOpenSym`: a symbol injected during instantiation
-  ## under the current proc replaces the captured symbol, otherwise the
-  ## captured node is used.
-  let inner = n[0]
-  result = inner
-  if inner.kind != nkSym: return
-  let id = newIdentNode(inner.sym.name, n.info)
-  c.isAmbiguous = false
-  let s2 = qualifiedLookUp(c, id, {})
-  if s2 != nil and not c.isAmbiguous and s2 != inner.sym:
-    # only consider symbols defined under the current proc:
-    var o = s2.owner
-    while o != nil:
-      if o == c.p.owner:
-        return id
-      o = o.owner
-
 proc semSymChoice(c: PContext, n: PNode, flags: TExprFlags = {}, expectedType: PType = nil): PNode =
   if n.kind == nkOpenSymChoice:
     result = semOpenSym(c, n, flags, expectedType,
@@ -384,7 +333,7 @@ proc isCastable(c: PContext; dst, src: PType, info: TLineInfo): bool =
   if skipTypes(dst, abstractInst).kind == tyBuiltInTypeClass:
     return false
   let conf = c.config
-  if conf.selectedGC in {gcArc, gcOrc, gcAtomicArc, gcYrc}:
+  if conf.selectedGC in {gcArc, gcOrc, gcAtomicArc}:
     let d = skipTypes(dst, abstractInst)
     let s = skipTypes(src, abstractInst)
     if d.kind == tyRef and s.kind == tyRef and s[0].isFinal != d[0].isFinal:
@@ -703,9 +652,6 @@ proc overloadedCallOpr(c: PContext, n: PNode): PNode =
     result = semExpr(c, result, flags = {efNoUndeclared})
 
 proc changeType(c: PContext; n: PNode, newType: PType, check: bool) =
-  template isViewTarget(t: PType): bool =
-    t.skipTypes({tyGenericInst, tyAlias, tySink}).kind in {tyVar, tyLent}
-
   case n.kind
   of nkCurly:
     for i in 0..<n.len:
@@ -734,15 +680,12 @@ proc changeType(c: PContext; n: PNode, newType: PType, check: bool) =
           if f == nil:
             globalError(c.config, m.info, "unknown identifier: " & m.sym.name.s)
             return
-          if not isViewTarget(f.typ):
-            changeType(c, n[i][1], f.typ, check)
+          changeType(c, n[i][1], f.typ, check)
         else:
-          if not isViewTarget(tup[i]):
-            changeType(c, n[i][1], tup[i], check)
+          changeType(c, n[i][1], tup[i], check)
     else:
       for i in 0..<n.len:
-        if not isViewTarget(tup[i]):
-          changeType(c, n[i], tup[i], check)
+        changeType(c, n[i], tup[i], check)
         when false:
           var m = n[i]
           var a = newNodeIT(nkExprColonExpr, m.info, newType[i])
@@ -765,7 +708,6 @@ proc changeType(c: PContext; n: PNode, newType: PType, check: bool) =
         localError(c.config, n.info, "cannot convert '" & n.sym.name.s &
                                          "' to '" & typeNameAndDesc(newType) & "'")
   else: discard
-
   n.typ = newType
 
 proc arrayConstrType(c: PContext, n: PNode): PType =
@@ -871,7 +813,7 @@ proc semArrayConstr(c: PContext, n: PNode, flags: TExprFlags; expectedType: PTyp
       inc(lastIndex)
     if isGeneric:
       for i in 0..<result.len:
-        if result[i].typ != nil and isIntLit(result[i].typ):
+        if isIntLit(result[i].typ):
           # generic instantiation strips int lit type which makes conversions fail
           result[i].typ = nil
       result.typ = nil # current result.typ is invalid, index type is nil
@@ -890,6 +832,9 @@ proc semArrayConstr(c: PContext, n: PNode, flags: TExprFlags; expectedType: PTyp
 proc fixAbstractType(c: PContext, n: PNode) =
   for i in 1..<n.len:
     let it = n[i]
+    if it == nil:
+      localError(c.config, n.info, "'$1' has nil child at index $2" % [renderTree(n, {renderNoComments}), $i])
+      return
     # do not get rid of nkHiddenSubConv for OpenArrays, the codegen needs it:
     if it.kind == nkHiddenSubConv and
         skipTypes(it.typ, abstractVar).kind notin {tyOpenArray, tyVarargs}:
@@ -1021,15 +966,12 @@ proc evalAtCompileTime(c: PContext, n: PNode): PNode =
     #  echo "SUCCESS evaluated at compile time: ", call.renderTree
 
 proc semStaticExpr(c: PContext, n: PNode; expectedType: PType = nil): PNode =
-  let oldErrorCount = c.config.errorCounter
   inc c.inStaticContext
   openScope(c)
   let a = semExprWithType(c, n, expectedType = expectedType)
   closeScope(c)
   dec c.inStaticContext
-  if a.findUnresolvedStatic != nil or
-      c.config.errorCounter != oldErrorCount:
-    return a
+  if a.findUnresolvedStatic != nil: return a
   result = evalStaticExpr(c.module, c.idgen, c.graph, a, c.p.owner)
   if result.isNil:
     localError(c.config, n.info, errCannotInterpretNodeX % renderTree(n))
@@ -1040,7 +982,7 @@ proc semStaticExpr(c: PContext, n: PNode; expectedType: PType = nil): PNode =
 
 proc semOverloadedCallAnalyseEffects(c: PContext, n: PNode, nOrig: PNode,
                                      flags: TExprFlags; expectedType: PType = nil): PNode =
-  if flags*{efInTypeof, efWantIterator, efWantIterable, efPreferIteratorForIterable} != {}:
+  if flags*{efInTypeof, efWantIterator, efWantIterable} != {}:
     # consider: 'for x in pReturningArray()' --> we don't want the restriction
     # to 'skIterator' anymore; skIterator is preferred in sigmatch already
     # for typeof support.
@@ -1067,8 +1009,7 @@ proc semOverloadedCallAnalyseEffects(c: PContext, n: PNode, nOrig: PNode,
         # See bug #2051:
         result[0] = newSymNode(errorSym(c, n))
       elif callee.kind == skIterator:
-        if result.typ.kind != tyIterable and
-            flags * {efWantIterable, efPreferIteratorForIterable} != {}:
+        if efWantIterable in flags:
           let typ = newTypeS(tyIterable, c)
           rawAddSon(typ, result.typ)
           result.typ = typ
@@ -1214,7 +1155,7 @@ proc semIndirectOp(c: PContext, n: PNode, flags: TExprFlags; expectedType: PType
           localError(c.config, n.info, msg)
         return errorNode(c, n)
     else:
-      result = compactVoidArgs(m.call)
+      result = m.call
       instGenericConvertersSons(c, result, m)
       markConvertersUsed(c, result)
 
@@ -1575,9 +1516,6 @@ proc builtinFieldAccess(c: PContext; n: PNode; flags: var TExprFlags): PNode =
       suggestExpr(c, n)
       if exactEquals(c.config.m.trackPos, n[1].info): suggestExprNoCheck(c, n)
 
-  if n[1].kind == nkOpenSym:
-    n[1] = resolveOpenSymDotRhs(c, n[1])
-
   var s = qualifiedLookUp(c, n, {checkAmbiguity, checkUndeclared, checkModule})
   if s != nil:
     if s.kind in OverloadableSyms:
@@ -1590,7 +1528,7 @@ proc builtinFieldAccess(c: PContext; n: PNode; flags: var TExprFlags): PNode =
     return
 
   # extra flags since LHS may become a call operand:
-  n[0] = semExprWithType(c, n[0], flags + {efDetermineType, efWantIterable, efAllowSymChoice})
+  n[0] = semExprWithType(c, n[0], flags+{efDetermineType, efWantIterable, efAllowSymChoice})
   #restoreOldStyleType(n[0])
   var i = considerQuotedIdent(c, n[1], n)
   var ty = n[0].typ
@@ -1723,9 +1661,6 @@ proc semDeref(c: PContext, n: PNode, flags: TExprFlags): PNode =
     n[0] = a
   result = n
   var t = skipTypes(n[0].typ, {tyGenericInst, tyVar, tyLent, tyAlias, tySink, tyOwned})
-  if t.kind == tyTypeDesc:
-    localError(c.config, n.info, "missing generic parameter")
-    return nil
   case t.kind
   of tyRef, tyPtr: n.typ = t.elementType
   of tyMetaTypes, tyFromExpr:
@@ -1905,22 +1840,6 @@ proc takeImplicitAddr(c: PContext, n: PNode; isLent: bool): PNode =
     n.typ = n.typ.elementType
   result.add(n)
 
-proc markResultVarIsPtr(c: PContext, x: PNode) {.inline.} =
-  ## Set `tfVarIsPtr` on the (result) sym node's type. Under IC that type can be a
-  ## NIF-loaded (Sealed) and interned instance which must not be mutated in place
-  ## (it could corrupt other users of the shared type, and the assert forbids it):
-  ## give this result its own copy carrying the flag, exactly like a from-source
-  ## compile has a fresh result type here.
-  if tfVarIsPtr in x.typ.flags: return
-  if x.typ.state == Sealed:
-    let fresh = copyType(x.typ, c.idgen, x.typ.owner)
-    fresh.incl tfVarIsPtr
-    x.typ = fresh
-    if x.kind == nkSym and x.sym.state != Sealed:
-      x.sym.typ = fresh
-  else:
-    x.typ.incl tfVarIsPtr
-
 proc asgnToResultVar(c: PContext, n, le, ri: PNode) {.inline.} =
   if le.kind == nkHiddenDeref:
     var x = le[0]
@@ -1928,10 +1847,10 @@ proc asgnToResultVar(c: PContext, n, le, ri: PNode) {.inline.} =
       if x.sym.kind == skResult and (x.typ.kind in {tyVar, tyLent} or classifyViewType(x.typ) != noView):
         n[0] = x # 'result[]' --> 'result'
         n[1] = takeImplicitAddr(c, ri, x.typ.kind == tyLent)
-        markResultVarIsPtr(c, x)
+        x.typ.incl tfVarIsPtr
         #echo x.info, " setting it for this type ", typeToString(x.typ), " ", n.info
       elif sfGlobal in x.sym.flags:
-        markResultVarIsPtr(c, x)
+        x.typ.incl tfVarIsPtr
 
 proc borrowCheck(c: PContext, n, le, ri: PNode) =
   const
@@ -2188,12 +2107,6 @@ proc semProcBody(c: PContext, n: PNode; expectedType: PType = nil): PNode =
 
   if c.p.owner.kind notin {skMacro, skTemplate} and
      c.p.resultSym != nil and c.p.resultSym.typ.isMetaType:
-    when defined(icDbgRefc):
-      echo "[icMetaRet] meta result type for ", c.p.owner.name.s, ": ",
-        typeToString(c.p.resultSym.typ), " kind=", c.p.resultSym.typ.kind,
-        " flags=", c.p.resultSym.typ.flags,
-        " uid=", c.p.resultSym.typ.uniqueId.module, ".", c.p.resultSym.typ.uniqueId.item,
-        " state=", c.p.resultSym.typ.state
     if isEmptyType(result.typ):
       # we inferred a 'void' return type:
       c.p.resultSym.typ = errorType(c)
@@ -2887,7 +2800,7 @@ proc semSetConstr(c: PContext, n: PNode, expectedType: PType = nil): PNode =
           expectedElementType = typ
     if isGeneric:
       for i in 0..<n.len:
-        if n[i].typ != nil and isIntLit(n[i].typ):
+        if isIntLit(n[i].typ):
           # generic instantiation strips int lit type which makes conversions fail
           n[i].typ = nil
         result.add n[i]
@@ -3000,7 +2913,7 @@ proc semTupleFieldsConstr(c: PContext, n: PNode, flags: TExprFlags; expectedType
     result.add n[i]
   if isGeneric:
     for i in 0..<result.len:
-      if result[i][1].typ != nil and isIntLit(result[i][1].typ):
+      if isIntLit(result[i][1].typ):
         # generic instantiation strips int lit type which makes conversions fail
         result[i][1].typ = nil
     result.typ = makeTypeFromExpr(c, result.copyTree)
@@ -3041,7 +2954,7 @@ proc semTuplePositionsConstr(c: PContext, n: PNode, flags: TExprFlags; expectedT
     addSonSkipIntLit(typ, n[i].typ.skipTypes({tySink}), c.idgen)
   if isGeneric:
     for i in 0..<result.len:
-      if result[i].typ != nil and isIntLit(result[i].typ):
+      if isIntLit(result[i].typ):
         # generic instantiation strips int lit type which makes conversions fail
         result[i].typ = nil
     result.typ = makeTypeFromExpr(c, result.copyTree)
@@ -3100,9 +3013,9 @@ proc semExportExcept(c: PContext, n: PNode): PNode =
 
 proc semExport(c: PContext, n: PNode): PNode =
   proc specialSyms(c: PContext; s: PSym) {.inline.} =
-    if s.kind == skConverter: addConverter(c, s)
+    if s.kind == skConverter: addConverter(c, LazySym(sym: s))
     elif s.kind == skType and s.typ != nil and s.typ.kind == tyEnum and sfPure in s.flags:
-      addPureEnum(c, s)
+      addPureEnum(c, LazySym(sym: s))
 
   result = newNodeI(nkExportStmt, n.info)
   for i in 0..<n.len:

compiler/semfold.nim

@@ -610,21 +610,10 @@ proc getConstExpr(m: PSym, n: PNode; idgen: IdGenerator; g: ModuleGraph): PNode
     var s = n.sym
     case s.kind
     of skEnumField:
-      when defined(icDbg):
-        if n.typ == nil:
-          echo "ENUMFIELD niltyp sym=", s.name.s, " symtyp=",
-            (if s.typ == nil: "nil" else: $s.typ.kind), " lazy=", nfLazyType in n.flags,
-            " symstate=", s.state, " symid=", s.itemId
       result = newIntNodeT(toInt128(s.position), n, idgen, g)
     of skConst:
       case s.magic
-      of mIsMainModule:
-        # Under `nim m` (IC) `sfMainModule` is set on every module that is being
-        # compiled (so it writes its own NIF), so it cannot answer `isMainModule`;
-        # the IC build file marks the real entry point with `--isMainModule:on`.
-        let isMain = if g.config.cmd == cmdM: g.config.isMainModule
-                     else: sfMainModule in m.flags
-        result = newIntNodeT(toInt128(ord(isMain)), n, idgen, g)
+      of mIsMainModule: result = newIntNodeT(toInt128(ord(sfMainModule in m.flags)), n, idgen, g)
       of mCompileDate: result = newStrNodeT(getDateStr(), n, g)
       of mCompileTime: result = newStrNodeT(getClockStr(), n, g)
       of mCpuEndian: result = newIntNodeT(toInt128(ord(CPU[g.config.target.targetCPU].endian)), n, idgen, g)

compiler/semgnrc.nim

@@ -129,14 +129,7 @@ proc semGenericStmtSymbol(c: PContext, n: PNode, s: PSym,
           result.typ = nil
     onUse(n.info, s)
   of skParam:
-    if s.owner == c.p.owner:
-      # Parameters of the routine currently being semchecked stay as local
-      # identifiers
-      result = n
-    else:
-      # Preserve captured outer parameters so nested generic procs can still
-      # see them after the generic pre-pass.
-      result = newSymNode(s, n.info)
+    result = n
     onUse(n.info, s)
   of skType:
     if (s.typ != nil) and

compiler/seminst.nim

@@ -119,44 +119,11 @@ proc freshGenSyms(c: PContext; n: PNode, owner, orig: PSym, symMap: var SymMappi
 
 proc addParamOrResult(c: PContext, param: PSym, kind: TSymKind)
 
-proc aliasLoadedTypedescParams(c: PContext, instantiated, orig: PSym): bool =
-  ## When the generic being instantiated had its body LOADED from a NIF (only
-  ## `nim m`/`nim nifc`, only for a generic owned by another module), that body
-  ## re-sems from plain identifiers — ast2nif serialises locals/params as idents,
-  ## not `nkSym`. A `T: typedesc[...]` param referenced as a type must then
-  ## resolve `T` to the bound type, but the instantiated skParam carries the
-  ## concrete type `instantiateProcType` typedesc-skipped it to, which an ident
-  ## lookup cannot use as a type name. Shadow each such param with an `skType`
-  ## alias of the same name in a fresh scope layer (the alias is exactly how Nim
-  ## models "this name denotes a type"). In-process bodies reach the param as
-  ## `nkSym` and never take this path, hence the command gate.
-  ##
-  ## Returns true iff a scope layer was opened; the caller must `closeScope`.
-  if c.config.cmd notin {cmdM, cmdNifC} or orig == nil or
-      orig.itemId.module == c.module.position or
-      orig.typ == nil or orig.typ.n == nil:
-    return false
-  result = false
-  let procParams = instantiated.typ.n
-  for i in 1..<min(procParams.len, orig.typ.n.len):
-    if orig.typ.n[i].kind != nkSym: continue
-    let origParamTyp = orig.typ.n[i].sym.typ
-    if origParamTyp != nil and origParamTyp.kind == tyTypeDesc and
-        tfUnresolved in origParamTyp.flags:
-      if not result:
-        openScope(c)
-        result = true
-      let p = procParams[i].sym
-      let alias = newSym(skType, p.name, c.idgen, instantiated, p.info)
-      alias.typ = p.typ
-      addDecl(c, alias)
-
 proc instantiateBody(c: PContext, n, params: PNode, result, orig: PSym) =
   if n[bodyPos].kind != nkEmpty:
     let procParams = result.typ.n
     for i in 1..<procParams.len:
       addDecl(c, procParams[i].sym)
-    let aliasLayer = aliasLoadedTypedescParams(c, result, orig)
     maybeAddResult(c, result, result.ast)
 
     inc c.inGenericInst
@@ -185,7 +152,6 @@ proc instantiateBody(c: PContext, n, params: PNode, result, orig: PSym) =
     excl(result, sfForward)
     trackProc(c, result, result.ast[bodyPos])
     dec c.inGenericInst
-    if aliasLayer: closeScope(c)
 
 proc fixupInstantiatedSymbols(c: PContext, s: PSym) =
   for i in 0..<c.generics.len:
@@ -279,7 +245,7 @@ proc instantiateProcType(c: PContext, pt: LayeredIdTable,
   let originalParams = result.n
   result.n = originalParams.shallowCopy
   for i in 1 ..< originalParams.len:
-    var resulti = originalParams[i].sym.typ
+    let resulti = originalParams[i].sym.typ
     # twrong_field_caching requires these 'resetIdTable' calls:
     if i > FirstParamAt:
       resetIdTable(cl.symMap)
@@ -292,11 +258,6 @@ proc instantiateProcType(c: PContext, pt: LayeredIdTable,
     let needsStaticSkipping = resulti.kind == tyFromExpr
     let needsTypeDescSkipping = resulti.kind == tyTypeDesc and tfUnresolved in resulti.flags
     if resulti.kind == tyFromExpr:
-      if resulti.state == Sealed:
-        # The generic was loaded from a NIF; do not brand the shared original.
-        # A tyFromExpr is a placeholder that `replaceTypeVarsT` resolves away,
-        # so a copy carries no identity that later comparisons could miss.
-        resulti = copyType(resulti, c.idgen, resulti.owner)
       resulti.incl tfNonConstExpr
     var paramType = replaceTypeVarsT(cl, resulti)
     if needsStaticSkipping:
@@ -315,12 +276,6 @@ proc instantiateProcType(c: PContext, pt: LayeredIdTable,
     let param = copySym(oldParam, c.idgen)
     setOwner(param, prc)
     param.typ = paramType
-    when defined(icDbgRefc):
-      echo "[icInst] ", prc.name.s, " param ", oldParam.name.s,
-        ": ", typeToString(resulti), " (kind=", resulti.kind,
-        " uid=", resulti.uniqueId.module, ".", resulti.uniqueId.item,
-        " flags=", resulti.flags, ") -> ", typeToString(paramType),
-        " (kind=", paramType.kind, ")"
 
     # The default value is instantiated and fitted against the final
     # concrete param type. We avoid calling `replaceTypeVarsN` on the
@@ -328,9 +283,6 @@ proc instantiateProcType(c: PContext, pt: LayeredIdTable,
     if oldParam.ast != nil:
       var def = oldParam.ast.copyTree
       if def.typ.kind == tyFromExpr:
-        if def.typ.state == Sealed:
-          # `copyTree` shares types; see the `resulti` comment above.
-          def.typ = copyType(def.typ, c.idgen, def.typ.owner)
         def.typ.incl tfNonConstExpr
       if not isIntLit(def.typ):
         def = prepareNode(cl, def)
@@ -422,11 +374,6 @@ proc generateInstance(c: PContext, fn: PSym, pt: LayeredIdTable,
   ## parameters to their concrete types within the generic instance.
   # no need to instantiate generic templates/macros:
   internalAssert c.config, fn.kind notin {skMacro, skTemplate}
-  # IC: instantiating `fn` consumes its generic body in the current module's
-  # sem — record a NeedsImpl (strong) edge to `fn`'s module. The iface cookie
-  # hashes only signatures now, so a generic body edit moves only the impl
-  # cookie, and just the modules that instantiated it re-sem.
-  recordIcImplDep(c.graph, fn)
   # generates an instantiated proc
   if c.instCounter > 50:
     globalError(c.config, info, "generic instantiation too nested")
@@ -508,10 +455,6 @@ proc generateInstance(c: PContext, fn: PSym, pt: LayeredIdTable,
     # This is needed for cyclic module dependencies where generic instances
     # may be created in one module but referenced from another.
     logGenericInstance(c.graph, result)
-    # Under IC the instance's NIF name must be canonical across modules:
-    # derive its `disamb` from the instantiation identity (generic +
-    # concrete types) instead of the per-module counter.
-    setInstanceDisamb(c.graph, result, fn, entry.concreteTypes)
     # bug #12985 bug #22913
     # TODO: use the context of the declaration of generic functions instead
     # TODO: consider fixing options as well

compiler/semmagic.nim

@@ -35,16 +35,23 @@ proc semAddr(c: PContext; n: PNode): PNode =
   let x = semExprWithType(c, n)
   if x.kind == nkSym:
     x.sym.flagsImpl.incl(sfAddrTaken)
-  let aa = isAssignable(c, x)
-  if aa notin {arLValue, arLocalLValue, arAddressableConst, arLentValue} and
-     (aa != arDiscriminant or c.inUncheckedAssignSection <= 0):
+  if isAssignable(c, x) notin {arLValue, arLocalLValue, arAddressableConst, arLentValue}:
     localError(c.config, n.info, errExprHasNoAddress)
   result.add x
   result.typ = makePtrType(c, x.typ.skipTypes({tySink}))
 
 proc semTypeOf(c: PContext; n: PNode): PNode =
-  let typExpr = semTypeOfImpl(c, n)
+  var m = BiggestInt 1 # typeOfIter
+  if n.len == 3:
+    let mode = semConstExpr(c, n[2])
+    if mode.kind != nkIntLit:
+      localError(c.config, n.info, "typeof: cannot evaluate 'mode' parameter at compile-time")
+    else:
+      m = mode.intVal
   result = newNodeI(nkTypeOfExpr, n.info)
+  inc c.inTypeofContext
+  defer: dec c.inTypeofContext # compiles can raise an exception
+  let typExpr = semExprWithType(c, n[1], if m == 1: {efInTypeof} else: {})
   result.add typExpr
   if typExpr.typ.kind == tyFromExpr:
     typExpr.typ.incl tfNonConstExpr
@@ -225,9 +232,10 @@ proc evalTypeTrait(c: PContext; traitCall: PNode, operand: PType, context: PSym)
   of "stripGenericParams":
     result = uninstantiate(operand).toNode(traitCall.info)
   of "supportsCopyMem":
-    result = newIntNodeT(toInt128(ord(supportsCopyMem(operand))), traitCall, c.idgen, c.graph)
-  of "canFormCycles":
-    result = newIntNodeT(toInt128(ord(types.canFormAcycle(c.graph, operand))), traitCall, c.idgen, c.graph)
+    let t = operand.skipTypes({tyVar, tyLent, tyGenericInst, tyAlias, tySink, tyInferred})
+    let complexObj = containsGarbageCollectedRef(t) or
+                     hasDestructor(t)
+    result = newIntNodeT(toInt128(ord(not complexObj)), traitCall, c.idgen, c.graph)
   of "hasDefaultValue":
     result = newIntNodeT(toInt128(ord(not operand.requiresInit)), traitCall, c.idgen, c.graph)
   of "isNamedTuple":
@@ -239,13 +247,10 @@ proc evalTypeTrait(c: PContext; traitCall: PNode, operand: PType, context: PSym)
     assert operand.kind == tyTuple, $operand.kind
     result = newIntNodeT(toInt128(operand.len), traitCall, c.idgen, c.graph)
   of "distinctBase":
-    var arg = operand.skipTypes(skippedTypes)
+    var arg = operand.skipTypes({tyGenericInst})
     let rec = semConstExpr(c, traitCall[2]).intVal != 0
-    while true:
-      let distinctArg = arg.skipTypes(skippedTypes + {tyGenericInst})
-      if distinctArg.kind != tyDistinct:
-        break
-      arg = distinctArg.base.skipTypes(skippedTypes)
+    while arg.kind == tyDistinct:
+      arg = arg.base.skipTypes(skippedTypes + {tyGenericInst})
       if not rec: break
     result = getTypeDescNode(c, arg, operand.owner, traitCall.info)
   of "rangeBase":
@@ -609,9 +614,9 @@ proc magicsAfterOverloadResolution(c: PContext, n: PNode,
   of mAsgn:
     case n[0].sym.name.s
     of "=", "=copy":
-      result = replaceHookMagic(c, n, attachedAsgn)
+      result = semAsgnOpr(c, n, nkAsgn)
     of "=sink":
-      result = replaceHookMagic(c, n, attachedSink)
+      result = semAsgnOpr(c, n, nkSinkAsgn)
     else:
       result = semShallowCopy(c, n, flags)
   of mIsPartOf: result = semIsPartOf(c, n, flags)

compiler/semobjconstr.nim

@@ -486,11 +486,6 @@ proc semObjConstr(c: PContext, n: PNode, flags: TExprFlags; expectedType: PType
       # we have to watch out, there are also 'owned proc' types that can be used
       # multiple times as long as they don't have closures.
       result.typ.incl tfHasOwned
-  if t.kind == tyForward and efDetermineType in flags:
-    # a forward object type does not error during determine-type analysis;
-    # it now stays unresolved long enough for the existing delayed field-default pass to resolve it after the type section finishes.
-    result.typ = t
-    return result
   if t.kind != tyObject:
     return localErrorNode(c, result, if t.kind != tyGenericBody:
       "object constructor needs an object type".dup(addTypeNodeDeclaredLoc(c.config, t))

compiler/sempass2.nim

@@ -84,8 +84,6 @@ type
     gcUnsafe, isRecursive, isTopLevel, hasSideEffect, inEnforcedGcSafe: bool
     isInnerProc: bool
     inEnforcedNoSideEffects: bool
-    isArrayIndexing: bool
-    currentExceptType: PType
     unknownRaises: seq[(PSym, TLineInfo)]
     currOptions: TOptions
     optionsStack: seq[(TOptions, TNoteKinds)]
@@ -149,49 +147,6 @@ proc isLocalSym(a: PEffects, s: PSym): bool =
   s.typ != nil and (s.kind in {skLet, skVar, skResult} or (s.kind == skParam and isOutParam(s.typ))) and
     sfGlobal notin s.flags and s.owner == a.owner
 
-proc isRangeSupertype(conf: ConfigRef; wider, narrower: PType): bool =
-  ## Check if `wider` type fully contains `narrower` type
-  ## Returns true if narrower fits entirely within wider (safe conversion)
-  if wider.isOrdinalType:
-    let wideFirst = firstOrd(conf, wider)
-    let wideLast = lastOrd(conf, wider)
-    let narrowFirst = firstOrd(conf, narrower)
-    let narrowLast = lastOrd(conf, narrower)
-    result = narrowFirst >= wideFirst and narrowLast <= wideLast
-  elif not narrower.isOrdinalType:
-    let wideFirst = firstFloat(wider)
-    let wideLast = lastFloat(wider)
-    let narrowFirst = firstFloat(narrower)
-    let narrowLast = lastFloat(narrower)
-    result = narrowFirst >= wideFirst and narrowLast <= wideLast
-  else:
-    # int -> float ranges; warn
-    result = false
-
-proc shouldWarnRangeConversion(conf: ConfigRef; info: TLineInfo; formalType, argType: PType): bool =
-  ## Determine if an implicit range conversion should warn
-  ## We warn on conversions that are likely to cause panics
-  let f = formalType.skipTypes({tyGenericInst, tyAlias, tySink, tyDistinct})
-  let a = argType.skipTypes({tyGenericInst, tyAlias, tySink, tyDistinct})
-  if f.kind == tyRange:
-    # Only warn if formal range doesn't fully contain argument range
-    # Check if the ranges don't perfectly overlap
-    if a.kind == tyInt and f.sym != nil and f.sym.owner != nil and
-        sfSystemModule in f.sym.owner.flags and
-        (f.sym.name.s == "Positive" or
-          f.sym.name.s == "Natural"):
-      # Positive and Natural are special cases that we do not warn on with
-      # ImplicitRangeConversion, but may warn on with systemRangeConversion
-      # if that warning is enabled.
-      if conf.hasWarn(warnSystemRangeConversion):
-        message(conf, info, warnSystemRangeConversion,
-              typeToString(argType) & " -> " & typeToString(formalType))
-      result = false
-    else:
-      result = not isRangeSupertype(conf, f, a)
-  else:
-    result = false
-
 proc lockLocations(a: PEffects; pragma: PNode) =
   if pragma.kind != nkExprColonExpr:
     localError(a.config, pragma.info, "locks pragma without argument")
@@ -497,33 +452,6 @@ proc addRaiseEffect(a: PEffects, e, comesFrom: PNode) =
     if not isDefectException(e.typ):
       throws(a.exc, e, comesFrom)
 
-proc skipHiddenConv(n: PNode): PNode =
-  result = n
-  while true:
-    case result.kind
-    of nkHiddenStdConv, nkHiddenSubConv:
-      result = result[1]
-    else: break
-
-proc addRaiseEffectsFromExpr(a: PEffects, e, comesFrom: PNode) =
-  if e.isNil:
-    return
-  case e.kind
-  of nkStmtList, nkStmtListExpr, nkBlockStmt, nkBlockExpr:
-    if e.len > 0:
-      addRaiseEffectsFromExpr(a, e.lastSon.skipHiddenConv, comesFrom)
-  of nkIfExpr, nkIfStmt:
-    for branch in items(e):
-      if branch.len > 0:
-        addRaiseEffectsFromExpr(a, branch.lastSon.skipHiddenConv, comesFrom)
-  of nkCaseStmt:
-    for i in 1..<e.len:
-      let branch = e[i]
-      if branch.len > 0:
-        addRaiseEffectsFromExpr(a, branch.lastSon.skipHiddenConv, comesFrom)
-  else:
-    addRaiseEffect(a, e, comesFrom)
-
 proc addTag(a: PEffects, e, comesFrom: PNode) =
   var aa = a.tags
   for i in 0..<aa.len:
@@ -649,25 +577,11 @@ proc trackTryStmt(tracked: PEffects, n: PNode) =
     let b = n[i]
     if b.kind == nkExceptBranch:
       setLen(tracked.init, oldState)
-      # If this except branch catches exactly one type, record it so an
-      # empty `raise` inside the branch can be inferred as re-raising that
-      # specific exception type instead of the generic `Exception`.
-      var savedExcept: PType = tracked.currentExceptType
-      var inferredExcept: PType = nil
-      if b.len == 2:
-        if b[0].isInfixAs():
-          assert(b[0][1].kind == nkType)
-          inferredExcept = b[0][1].typ
-        else:
-          assert(b[0].kind == nkType)
-          inferredExcept = b[0].typ
-      tracked.currentExceptType = inferredExcept
       for j in 0..<b.len - 1:
         if b[j].isInfixAs(): # skips initialization checks
           assert(b[j][2].kind == nkSym)
           tracked.init.add b[j][2].sym.id
       track(tracked, b[^1])
-      tracked.currentExceptType = savedExcept
       for i in oldState..<tracked.init.len:
         addToIntersection(inter, tracked.init[i], bsNone)
     else:
@@ -836,10 +750,6 @@ proc trackOperandForIndirectCall(tracked: PEffects, n: PNode, formals: PType; ar
         markSideEffect(tracked, a, n.info)
   let paramType = if formals != nil and argIndex < formals.signatureLen: formals[argIndex] else: nil
   if paramType != nil and paramType.kind in {tyVar}:
-    let arg = n.skipAddr()
-    if isSsoStringIndex(tracked.config, arg):
-      localError(tracked.config, arg.info,
-        "expression '$1' is immutable, not 'var'" % renderNotLValue(arg))
     invalidateFacts(tracked.guards, n)
     if n.kind == nkSym and isLocalSym(tracked, n.sym):
       makeVolatile(tracked, n.sym)
@@ -1195,7 +1105,7 @@ proc trackCall(tracked: PEffects; n: PNode) =
     var (isHook, opKind) = findHookKind(a.sym.name.s)
     if isHook:
       # rebind type bounds operations after createTypeBoundOps call
-      let t = n[1].typ.skipTypes({tyAlias, tyVar, tySink})
+      let t = n[1].typ.skipTypes({tyAlias, tyVar})
       if a.sym != getAttachedOp(tracked.graph, t, opKind):
         createTypeBoundOps(tracked, t, n.info, explicit = true)
         # replace builtin hooks with lifted ones
@@ -1235,7 +1145,6 @@ type
     enforcedGcSafety, enforceNoSideEffects: bool
     oldExc, oldTags, oldForbids: int
     exc, tags, forbids: PNode
-    excSource, tagsSource, forbidsSource: PNode
 
 proc createBlockContext(tracked: PEffects): PragmaBlockContext =
   var oldForbidsLen = 0
@@ -1258,18 +1167,17 @@ proc unapplyBlockContext(tracked: PEffects; bc: PragmaBlockContext) =
     # anything about 'raises' in the 'cast' at all. Same applies for 'tags'.
     setLen(tracked.exc.sons, bc.oldExc)
     for e in bc.exc:
-      addRaiseEffect(tracked, e, if bc.excSource != nil: bc.excSource else: e)
+      addRaiseEffect(tracked, e, e)
   if bc.tags != nil:
     setLen(tracked.tags.sons, bc.oldTags)
     for t in bc.tags:
-      addTag(tracked, t, if bc.tagsSource != nil: bc.tagsSource else: t)
+      addTag(tracked, t, t)
   if bc.forbids != nil:
     setLen(tracked.forbids.sons, bc.oldForbids)
     for t in bc.forbids:
-      addNotTag(tracked, t, if bc.forbidsSource != nil: bc.forbidsSource else: t)
+      addNotTag(tracked, t, t)
 
-proc castBlock(tracked: PEffects, castPragma: PNode, bc: var PragmaBlockContext) =
-  let pragma = castPragma[1]
+proc castBlock(tracked: PEffects, pragma: PNode, bc: var PragmaBlockContext) =
   case whichPragma(pragma)
   of wGcSafe:
     bc.enforcedGcSafety = true
@@ -1282,7 +1190,6 @@ proc castBlock(tracked: PEffects, castPragma: PNode, bc: var PragmaBlockContext)
     else:
       bc.tags = newNodeI(nkArgList, pragma.info)
       bc.tags.add n
-    bc.tagsSource = castPragma
   of wForbids:
     let n = pragma[1]
     if n.kind in {nkCurly, nkBracket}:
@@ -1290,7 +1197,6 @@ proc castBlock(tracked: PEffects, castPragma: PNode, bc: var PragmaBlockContext)
     else:
       bc.forbids = newNodeI(nkArgList, pragma.info)
       bc.forbids.add n
-    bc.forbidsSource = castPragma
   of wRaises:
     let n = pragma[1]
     if n.kind in {nkCurly, nkBracket}:
@@ -1298,7 +1204,6 @@ proc castBlock(tracked: PEffects, castPragma: PNode, bc: var PragmaBlockContext)
     else:
       bc.exc = newNodeI(nkArgList, pragma.info)
       bc.exc.add n
-    bc.excSource = castPragma
   of wUncheckedAssign:
     discard "handled in sempass1"
   else:
@@ -1335,8 +1240,6 @@ proc allowCStringConv(n: PNode): bool =
 
 proc track(tracked: PEffects, n: PNode) =
   case n.kind
-  of nkTypeOfExpr:
-    discard "typeof() never evaluates its operand; not a definite-assignment use"
   of nkSym:
     useVar(tracked, n)
     if n.sym.typ != nil and tfHasAsgn in n.sym.typ.flags:
@@ -1353,7 +1256,7 @@ proc track(tracked: PEffects, n: PNode) =
     if n[0].kind != nkEmpty:
       n[0].info = n.info
       #throws(tracked.exc, n[0])
-      addRaiseEffectsFromExpr(tracked, n[0], n)
+      addRaiseEffect(tracked, n[0], n)
       for i in 0..<n.safeLen:
         track(tracked, n[i])
       createTypeBoundOps(tracked, n[0].typ, n.info)
@@ -1361,14 +1264,7 @@ proc track(tracked: PEffects, n: PNode) =
       # A `raise` with no arguments means we're going to re-raise the exception
       # being handled or, if outside of an `except` block, a `ReraiseDefect`.
       # Here we add a `Exception` tag in order to cover both the cases.
-      if tracked.currentExceptType != nil:
-        var en = newNode(nkType)
-        en.typ = tracked.currentExceptType
-        en.info = n.info
-        addRaiseEffect(tracked, en, nil)
-        createTypeBoundOps(tracked, tracked.currentExceptType, n.info)
-      else:
-        addRaiseEffect(tracked, createRaise(tracked.graph, n), nil)
+      addRaiseEffect(tracked, createRaise(tracked.graph, n), nil)
   of nkCallKinds:
     trackCall(tracked, n)
   of nkDotExpr:
@@ -1554,7 +1450,7 @@ proc track(tracked: PEffects, n: PNode) =
       of wNoSideEffect:
         bc.enforceNoSideEffects = true
       of wCast:
-        castBlock(tracked, pragmaList[i], bc)
+        castBlock(tracked, pragmaList[i][1], bc)
       else:
         discard
     applyBlockContext(tracked, bc)
@@ -1586,12 +1482,6 @@ proc track(tracked: PEffects, n: PNode) =
       message(tracked.config, n.info, warnPtrToCstringConv,
           $n[1].typ)
 
-    # Check for implicit range conversions
-    if n.kind == nkHiddenStdConv and (not tracked.isArrayIndexing) and
-          n[1].kind notin {nkCharLit..nkUInt64Lit, nkFloatLit..nkFloat128Lit} and
-          shouldWarnRangeConversion(tracked.config, n.info, n.typ, n[1].typ):
-      message(tracked.config, n.info, warnImplicitRangeConversion,
-              typeToString(n[1].typ) & " -> " & typeToString(n.typ))
 
     let t = n.typ.skipTypes(abstractInst)
     if t.kind == tyEnum:
@@ -1630,12 +1520,7 @@ proc track(tracked: PEffects, n: PNode) =
         checkBounds(tracked, n[0], n[1])
     track(tracked, n[0])
     dec tracked.leftPartOfAsgn
-    for i in 1 ..< n.len:
-      if i == 1:
-        tracked.isArrayIndexing = true
-      track(tracked, n[i])
-      if i == 1:
-        tracked.isArrayIndexing = false
+    for i in 1 ..< n.len: track(tracked, n[i])
     inc tracked.leftPartOfAsgn
   of nkError:
     localError(tracked.config, n.info, errorToString(tracked.config, n))
@@ -1807,7 +1692,7 @@ proc trackProc*(c: PContext; s: PSym, body: PNode) =
       let param = params[i].sym
       let typ = param.typ
       if isSinkTypeForParam(typ) or
-          (t.config.selectedGC in {gcArc, gcOrc, gcYrc, gcAtomicArc} and
+          (t.config.selectedGC in {gcArc, gcOrc, gcAtomicArc} and
             (isClosure(typ.skipTypes(abstractInst)) or param.id in t.escapingParams)):
         createTypeBoundOps(t, typ, param.info)
       if isOutParam(typ) and param.id notin t.init and s.magic == mNone:

compiler/semstmts.nim

@@ -1096,12 +1096,7 @@ proc symForVar(c: PContext, n: PNode): PSym =
 proc semForVars(c: PContext, n: PNode; flags: TExprFlags): PNode =
   result = n
   let iterBase = n[^2].typ
-  let iterType =
-    if iterBase.kind == tyIterable:
-      iterBase.skipModifier
-    else:
-      skipTypes(iterBase, {tyAlias, tySink, tyOwned})
-  var iter = skipTypes(iterType, {tyGenericInst})
+  var iter = skipTypes(iterBase, {tyGenericInst, tyAlias, tySink, tyOwned})
   var iterAfterVarLent = iter.skipTypes({tyGenericInst, tyAlias, tyLent, tyVar})
   # n.len == 3 means that there is one for loop variable
   # and thus no tuple unpacking:
@@ -1134,9 +1129,10 @@ proc semForVars(c: PContext, n: PNode; flags: TExprFlags): PNode =
       else:
         var v = symForVar(c, n[0])
         if getCurrOwner(c).kind == skModule: incl(v, sfGlobal)
-        # Use `iterType` here: it removes outer `tyIterable` / alias-like wrappers
-        # from the loop source, but still preserves `tyGenericInst` for the loop var.
-        v.typ = iterType
+        # BUGFIX: don't use `iter` here as that would strip away
+        # the ``tyGenericInst``! See ``tests/compile/tgeneric.nim``
+        # for an example:
+        v.typ = iterBase
         n[0] = newSymNode(v)
         if sfGenSym notin v.flags and not isDiscardUnderscore(v): addDecl(c, v)
         elif v.owner == nil: setOwner(v, getCurrOwner(c))
@@ -1200,14 +1196,14 @@ proc semForVars(c: PContext, n: PNode; flags: TExprFlags): PNode =
   c.p.breakInLoop = oldBreakInLoop
   dec(c.p.nestedLoopCounter)
 
-proc implicitIterator(c: PContext, it: string, arg: PNode, flags: TExprFlags): PNode =
+proc implicitIterator(c: PContext, it: string, arg: PNode): PNode =
   result = newNodeI(nkCall, arg.info)
   result.add(newIdentNode(getIdent(c.cache, it), arg.info))
   if arg.typ != nil and arg.typ.kind in {tyVar, tyLent}:
     result.add newDeref(arg)
   else:
     result.add arg
-  result = semExprNoDeref(c, result, flags + {efWantIterator})
+  result = semExprNoDeref(c, result, {efWantIterator})
 
 proc isTrivalStmtExpr(n: PNode): bool =
   for i in 0..<n.len-1:
@@ -1293,8 +1289,7 @@ proc semFor(c: PContext, n: PNode; flags: TExprFlags): PNode =
   if result != nil: return result
   openScope(c)
   result = n
-  let iteratorFlags = flags * {efPreferIteratorForIterable}
-  n[^2] = semExprNoDeref(c, n[^2], iteratorFlags + {efWantIterator})
+  n[^2] = semExprNoDeref(c, n[^2], {efWantIterator})
   var call = n[^2]
 
   if call.kind == nkStmtListExpr and (isTrivalStmtExpr(call) or (call.lastSon.kind in nkCallKinds and call.lastSon[0].sym.kind == skIterator)):
@@ -1314,16 +1309,14 @@ proc semFor(c: PContext, n: PNode; flags: TExprFlags): PNode =
   elif not isCallExpr or call[0].kind != nkSym or
       call[0].sym.kind != skIterator:
     if n.len == 3:
-      n[^2] = implicitIterator(c, "items", n[^2], iteratorFlags)
+      n[^2] = implicitIterator(c, "items", n[^2])
     elif n.len == 4:
-      n[^2] = implicitIterator(c, "pairs", n[^2], iteratorFlags)
+      n[^2] = implicitIterator(c, "pairs", n[^2])
     else:
       localError(c.config, n[^2].info, "iterator within for loop context expected")
     result = semForVars(c, n, flags)
   else:
     result = semForVars(c, n, flags)
-  if n[^2].typ != nil and n[^2].typ.kind == tyIterable:
-    n[^2].typ = n[^2].typ.skipModifier
   # propagate any enforced VoidContext:
   if n[^1].typ == c.enforceVoidContext:
     result.typ = c.enforceVoidContext
@@ -1808,35 +1801,15 @@ proc checkForMetaFields(c: PContext; n: PNode; hasError: var bool) =
     internalAssert c.config, false
 
 proc typeSectionFinalPass(c: PContext, n: PNode) =
-  # each top level type needs to be processed, each epoch should reify at least one
-  var remainingOwners = initIntSet()
-  for (owner, _, _) in c.forwardTypeUpdates:
-    remainingOwners.incl owner.id
-  
-  while c.forwardTypeUpdates.len > 0:
-    let pending = move c.forwardTypeUpdates
-    var madeProgress = false
-
-    for (owner, typ, typeNode) in pending:
-      # types that need to be updated due to containing forward types
-      # and their corresponding type nodes
-      # for example generic invocations of forward types end up here
-      var reified = semTypeNode(c, typeNode, nil)
-      assert reified != nil
-      assignType(typ, reified)
-      typ.itemId = reified.itemId  # same id
-      if containsForwardType(typ):
-        c.forwardTypeUpdates.add (owner, typ, typeNode)
-      elif not remainingOwners.missingOrExcl(owner.id):
-        madeProgress = true
-    
-    if not madeProgress:
-      # can't error here unfortunately
-      break
-
-  for (owner, field, expectedType) in c.forwardFieldUpdates:
-    semDelayedFieldDefault(c, owner, expectedType, field)
-  c.forwardFieldUpdates = @[]
+  for (typ, typeNode) in c.forwardTypeUpdates:
+    # types that need to be updated due to containing forward types
+    # and their corresponding type nodes
+    # for example generic invocations of forward types end up here
+    var reified = semTypeNode(c, typeNode, nil)
+    assert reified != nil
+    assignType(typ, reified)
+    typ.itemId = reified.itemId     # same id
+  c.forwardTypeUpdates = @[]
   for i in 0..<n.len:
     var a = n[i]
     if a.kind == nkCommentStmt: continue
@@ -1872,13 +1845,6 @@ proc typeSectionFinalPass(c: PContext, n: PNode) =
           let baseType = s.typ.safeSkipTypes(abstractPtrs)
           if baseType.kind in {tyObject, tyTuple} and not baseType.n.isNil:
             checkForMetaFields(c, baseType.n, hasError)
-
-        if s.typ.kind in {tySet, tyArray, tySequence, tyUncheckedArray} and s.typ.elementType.kind == tyNone:
-          # magic generics are not filled but tyNone is added to its elements by default,
-          # we lift them to tyBuiltInTypeClass here
-          s.typ = newTypeS(tyBuiltInTypeClass, c,
-                    newTypeS(s.typ.kind, c))
-
         if not hasError:
           checkConstructedType(c.config, s.info, s.typ)
   #instAllTypeBoundOp(c, n.info)
@@ -2202,7 +2168,7 @@ proc bindTypeHook(c: PContext; s: PSym; n: PNode; op: TTypeAttachedOp) =
   template notRefc: bool =
     # fixes refc with non-var destructor; cancel warnings (#23156)
     c.config.backend == backendJs or
-      c.config.selectedGC in {gcArc, gcAtomicArc, gcOrc, gcYrc}
+      c.config.selectedGC in {gcArc, gcAtomicArc, gcOrc}
   let cond = case op
              of attachedWasMoved:
                t.len == 2 and t.returnType == nil and t.firstParamType.kind == tyVar
@@ -2579,9 +2545,6 @@ proc semProcAux(c: PContext, n: PNode, kind: TSymKind,
   if not hasProto:
     implicitPragmas(c, s, n.info, validPragmas)
 
-  if {sfError, sfExportc} * s.flags == {sfError, sfExportc}:
-    localError(c.config, n.info, "{.error.} and {.exportc.} pragmas are incompatible")
-
   if n[pragmasPos].kind != nkEmpty and sfBorrow notin s.flags:
     setEffectsForProcType(c.graph, s.typ, n[pragmasPos], s)
   s.typ.incl tfEffectSystemWorkaround
@@ -2625,14 +2588,6 @@ proc semProcAux(c: PContext, n: PNode, kind: TSymKind,
     n[genericParamsPos] = proto.ast[genericParamsPos]
     n[paramsPos] = proto.ast[paramsPos]
     n[pragmasPos] = proto.ast[pragmasPos]
-    # miscPos holds this definition's *original* generic-param node (kept for
-    # error messages, see setGenericParamsMisc / issue #1713). For an impl that
-    # resolves to a forward decl, that node was analysed under the now-discarded
-    # impl symbol and its generic-param constraint types are owned by it. Adopt
-    # the prototype's miscPos so the discarded impl sym is fully unreachable —
-    # otherwise it leaks (via `proto.ast = n` below) as a type owner and gets
-    # serialized as a phantom duplicate overload under IC.
-    n[miscPos] = proto.ast[miscPos]
     if n[namePos].kind != nkSym: internalError(c.config, n.info, "semProcAux")
     n[namePos].sym = proto
     if importantComments(c.config) and proto.ast.comment.len > 0:
@@ -2650,11 +2605,6 @@ proc semProcAux(c: PContext, n: PNode, kind: TSymKind,
       elif s.name.s == "()" and callOperator notin c.features:
         localError(c.config, n.info, "the overloaded " & s.name.s &
           " operator has to be enabled with {.experimental: \"callOperator\".}")
-    elif sfImportc notin s.flags and (s.name.s == ">" or s.name.s == ">=" or s.name.s == "!="):
-      # ignore imported procs as these operators in backend language might have different semantics
-      let op1 = if s.name.s == "!=": "==" elif s.name.s == ">": "<" else: "<="
-      message(c.config, n.info, warnInvalidCmpOp, "define `" & op1 & "` instead of `" & s.name.s & "` to implement user defined comparison operator. " &
-              "it allows you to use `" & s.name.s & "` automatically.")
 
   if sfBorrow in s.flags and c.config.cmd notin cmdDocLike:
     result[bodyPos] = c.graph.emptyNode
@@ -2826,7 +2776,7 @@ proc semConverterDef(c: PContext, n: PNode): PNode =
   var t = s.typ
   if t.returnType == nil: localError(c.config, n.info, errXNeedsReturnType % "converter")
   if t.len != 2: localError(c.config, n.info, "a converter takes exactly one argument")
-  addConverterDef(c, s)
+  addConverterDef(c, LazySym(sym: s))
 
 proc semMacroDef(c: PContext, n: PNode): PNode =
   result = semProcAux(c, n, skMacro, macroPragmas)
@@ -2949,15 +2899,13 @@ proc semPragmaBlock(c: PContext, n: PNode; expectedType: PType = nil): PNode =
 proc semStaticStmt(c: PContext, n: PNode): PNode =
   #echo "semStaticStmt"
   #writeStackTrace()
-  let oldErrorCount = c.config.errorCounter
   inc c.inStaticContext
   openScope(c)
   let a = semStmt(c, n[0], {})
   closeScope(c)
   dec c.inStaticContext
   n[0] = a
-  if c.config.errorCounter == oldErrorCount:
-    evalStaticStmt(c.module, c.idgen, c.graph, a, c.p.owner)
+  evalStaticStmt(c.module, c.idgen, c.graph, a, c.p.owner)
   when false:
     # for incremental replays, keep the AST as required for replays:
     result = n

compiler/semtempl.nim

@@ -925,4 +925,4 @@ proc semPattern(c: PContext, n: PNode; s: PSym): PNode =
     elif result.len == 0:
       localError(c.config, n.info, "a pattern cannot be empty")
   closeScope(c)
-  addPattern(c, s)
+  addPattern(c, LazySym(sym: s))

compiler/semtypes.nim

@@ -210,7 +210,7 @@ proc semEnum(c: PContext, n: PNode, prev: PType): PType =
     )
 
   if isPure and sfExported in result.sym.flags:
-    addPureEnum(c, result.sym)
+    addPureEnum(c, LazySym(sym: result.sym))
   if tfNotNil in e.typ.flags and not hasNull:
     result.incl tfRequiresInit
   setToStringProc(c.graph, result, genEnumToStrProc(result, n.info, c.graph, c.idgen))
@@ -223,7 +223,7 @@ proc semSet(c: PContext, n: PNode, prev: PType): PType =
     if base.kind in {tyGenericInst, tyAlias, tySink}: base = skipModifier(base)
     if base.kind notin {tyGenericParam, tyGenericInvocation}:
       if base.kind == tyForward:
-        c.forwardTypeUpdates.add (getCurrOwner(c), result, n)
+        c.forwardTypeUpdates.add (base, n[1])
       elif not isOrdinalType(base, allowEnumWithHoles = true):
         localError(c.config, n.info, errOrdinalTypeExpected % typeToString(base, preferDesc))
       elif lengthOrd(c.config, base) > MaxSetElements:
@@ -318,62 +318,6 @@ proc fitDefaultNode(c: PContext, n: var PNode, expectedType: PType) =
     typeAllowedCheck(c, n.info, n.typ, skConst, {taProcContextIsNotMacro, taIsDefaultField})
   dec c.inStaticContext
 
-proc containsForwardTypeAux(t: PType; seen: var IntSet): bool
-
-proc containsForwardTypeAux(n: PNode; seen: var IntSet): bool =
-  result = false
-  if n.isNil or n.kind in nkLiterals + {nkNilLit, nkEmpty, nkType}:
-    return
-  if containsForwardTypeAux(n.typ, seen) or
-     (n.kind == nkSym and n.sym.typ != n.typ and containsForwardTypeAux(n.sym.typ, seen)):
-    return true
-
-  for i in 0 ..< n.safeLen:
-    if containsForwardTypeAux(n[i], seen):
-      return true
-
-proc containsForwardTypeAux(t: PType; seen: var IntSet): bool =
-  result = false
-  if t.isNil:
-    return
-  if t.kind == tyForward:
-    return true
-
-  if not containsOrIncl(seen, t.id):
-    if containsForwardTypeAux(t.n, seen):
-      return true
-
-    for i in 0 ..< t.len:
-      if containsForwardTypeAux(t[i], seen):
-        return true
-
-proc containsForwardType(arg: PNode): bool =
-  var seen = initIntSet()
-  containsForwardTypeAux(arg, seen)
-
-proc containsForwardType(t: PType): bool =
-  var seen = initIntSet()
-  containsForwardTypeAux(t, seen)
-
-proc semFieldDefault(c: PContext; owner, expectedType: PType; field: PNode): PType =
-  result = expectedType
-  field[^1] = semExprWithType(c, field[^1], {efDetermineType, efAllowSymChoice}, result)
-  if result == nil:
-    result = field[^1].typ
-
-  if c.inGenericContext == 0:
-    if containsForwardType(field[^1]):
-      c.forwardFieldUpdates.add (owner, field, result)
-    else:
-      fitDefaultNode(c, field[^1], result)
-      result = field[^1].typ.skipIntLit(c.idgen)
-      propagateToOwner(owner, result)
-
-proc semDelayedFieldDefault(c: PContext; owner, expectedType: PType; field: PNode) =
-  resetSemFlag(field[^1])
-  fitDefaultNode(c, field[^1], expectedType)
-  propagateToOwner(owner, field[^1].typ.skipIntLit(c.idgen))
-
 proc isRecursiveType*(t: PType): bool =
   # handle simple recusive types before typeFinalPass
   var cycleDetector = initIntSet()
@@ -512,13 +456,7 @@ proc semArrayIndex(c: PContext, n: PNode): PType =
         if c.inGenericContext > 0: result.incl tfUnresolved
       else:
         result = e.typ.skipTypes({tyTypeDesc})
-        if result.state != Sealed:
-          # For a type loaded from the IC cache we skip the flag instead of
-          # mutating (or copying) the type: tfImplicitStatic has no readers in
-          # the compiler, and a copy would get a fresh itemId, breaking enum
-          # identity (`sameEnumTypes` compares ids) — `arr[enumVal]` on an
-          # `array[LoadedEnum, T]` would no longer typecheck.
-          result.incl tfImplicitStatic
+        result.incl tfImplicitStatic
     elif e.kind in (nkCallKinds + {nkBracketExpr}) and hasUnresolvedArgs(c, e):
       if not isOrdinalType(e.typ.skipTypes({tyStatic, tyAlias, tyGenericInst, tySink})):
         localError(c.config, n[1].info, errOrdinalTypeExpected % typeToString(e.typ, preferDesc))
@@ -612,7 +550,13 @@ proc semTuple(c: PContext, n: PNode, prev: PType): PType =
     var hasDefaultField = a[^1].kind != nkEmpty
     if hasDefaultField:
       typ = if a[^2].kind != nkEmpty: semTypeNode(c, a[^2], nil) else: nil
-      typ = semFieldDefault(c, result, typ, a)
+      if c.inGenericContext > 0:
+        a[^1] = semExprWithType(c, a[^1], {efDetermineType, efAllowSymChoice}, typ)
+        if typ == nil:
+          typ = a[^1].typ
+      else:
+        fitDefaultNode(c, a[^1], typ)
+        typ = a[^1].typ.skipIntLit(c.idgen)
     elif a[^2].kind != nkEmpty:
       typ = semTypeNode(c, a[^2], nil)
       if c.graph.config.isDefined("nimPreviewRangeDefault") and typ.skipTypes(abstractInst).kind == tyRange:
@@ -978,7 +922,14 @@ proc semRecordNodeAux(c: PContext, n: PNode, check: var IntSet, pos: var int,
     var hasDefaultField = n[^1].kind != nkEmpty
     if hasDefaultField:
       typ = if n[^2].kind != nkEmpty: semTypeNode(c, n[^2], nil) else: nil
-      typ = semFieldDefault(c, rectype, typ, n)
+      if c.inGenericContext > 0:
+        n[^1] = semExprWithType(c, n[^1], {efDetermineType, efAllowSymChoice}, typ)
+        if typ == nil:
+          typ = n[^1].typ
+      else:
+        fitDefaultNode(c, n[^1], typ)
+        typ = n[^1].typ.skipIntLit(c.idgen)
+        propagateToOwner(rectype, typ)
     elif n[^2].kind == nkEmpty:
       localError(c.config, n.info, errTypeExpected)
       typ = errorType(c)
@@ -1063,7 +1014,7 @@ proc skipGenericInvocation(t: PType): PType {.inline.} =
 proc tryAddInheritedFields(c: PContext, check: var IntSet, pos: var int,
                         obj: PType, n: PNode, isPartial = false, innerObj: PType = nil): bool =
   if ((not isPartial) and (obj.kind notin {tyObject, tyGenericParam} or tfFinal in obj.flags)) or
-    (innerObj != nil and obj.id == innerObj.id):
+    (innerObj != nil and obj.sym.id == innerObj.sym.id):
     localError(c.config, n.info, "Cannot inherit from: '" & $obj & "'")
     result = false
   elif obj.kind == tyObject:
@@ -1121,7 +1072,7 @@ proc semObjectNode(c: PContext, n: PNode, prev: PType; flags: TTypeFlags): PType
   if needsForwardUpdate:
     # if the inherited object is a forward type,
     # the entire object needs to be checked again
-    c.forwardTypeUpdates.add (getCurrOwner(c), result, n) # we retry in the final pass
+    c.forwardTypeUpdates.add (result, n) # we retry in the final pass
   rawAddSon(result, realBase)
   if realBase == nil and tfInheritable in flags:
     result.incl tfInheritable
@@ -1198,7 +1149,7 @@ proc semAnyRef(c: PContext; n: PNode; kind: TTypeKind; prev: PType): PType =
       result = t
     else: discard
     if result.kind == tyRef and
-        c.config.selectedGC in {gcArc, gcOrc, gcAtomicArc, gcYrc} and
+        c.config.selectedGC in {gcArc, gcOrc, gcAtomicArc} and
         tfTriggersCompileTime notin result.flags:
       result.incl tfHasAsgn
 
@@ -1252,15 +1203,7 @@ proc addImplicitGeneric(c: PContext; typeClass: PType, typId: PIdent;
   # is this a bindOnce type class already present in the param list?
   for i in 0..<genericParams.len:
     if genericParams[i].sym.name.id == finalTypId.id:
-      if typeClass.kind == tyStatic and genericParams[i].typ.kind != tyStatic:
-        # The base type (e.g. from `auto`) was already added as a generic param,
-        # but `static[auto]` requires upgrading it to a `tyStatic` wrapper so
-        # it is instantiated as a compile-time value (`skConst`).
-        genericParams[i].sym.linkTo(typeClass)
-        typeClass.incl tfImplicitTypeParam
-        return typeClass
-      else:
-        return genericParams[i].typ
+      return genericParams[i].typ
 
   let owner = if typeClass.sym != nil: typeClass.sym
               else: getCurrOwner(c)
@@ -1361,7 +1304,7 @@ proc liftParamType(c: PContext, procKind: TSymKind, genericParams: PNode,
 
     for i in 0..<paramType.len - 1:
       if paramType[i].kind == tyStatic:
-        var staticCopy = paramType[i].exactReplica(c.idgen)
+        var staticCopy = paramType[i].exactReplica
         staticCopy.incl tfInferrableStatic
         result.rawAddSon staticCopy
       else:
@@ -1769,7 +1712,7 @@ proc semGeneric(c: PContext, n: PNode, s: PSym, prev: PType): PType =
     for i in 1..<n.len:
       var elem = semGenericParamInInvocation(c, n[i])
       addToResult(elem, true)
-    c.forwardTypeUpdates.add (getCurrOwner(c), result, n)
+    c.forwardTypeUpdates.add (result, n)
     return
   elif t.kind != tyGenericBody:
     # we likely got code of the form TypeA[TypeB] where TypeA is
@@ -1796,7 +1739,6 @@ proc semGeneric(c: PContext, n: PNode, s: PSym, prev: PType): PType =
     var isConcrete = true
     let rType = m.call[0].typ
     let mIndex = if rType != nil: rType.len - 1 else: -1
-    var hasForwardTypeParam = false
     for i in 1..<m.call.len:
       var typ = m.call[i].typ
       # is this a 'typedesc' *parameter*? If so, use the typedesc type,
@@ -1813,40 +1755,13 @@ proc semGeneric(c: PContext, n: PNode, s: PSym, prev: PType): PType =
           skip = false
         addToResult(typ, skip)
 
-      if typ.kind == tyForward:
-        hasForwardTypeParam = true
-
     if isConcrete:
       if s.ast == nil and s.typ.kind != tyCompositeTypeClass:
         # XXX: What kind of error is this? is it still relevant?
         localError(c.config, n.info, errCannotInstantiateX % s.name.s)
         result = newOrPrevType(tyError, prev, c)
-      elif containsGenericInvocationWithForward(n[0]) or hasForwardTypeParam:
-        # isConcrete == false means this generic type is not instanciated here because
-        # it invoked with generic parameters.
-        # Even if isConcrete == true, don't instanciate it now if there are
-        # unresolved `tyForward` type params.
-        # Such `tyForward` type params will be semchecked later and we can
-        # instanciate this next time.
-        # Some generic types like std/options.Option[T] need the kind of the
-        # given type argument before their fields can be resolved.
-
-        # return `tyForward` instead of `tyGenericInvocation` because:
-        # ```nim
-        #   type Foo = object
-        #     x: Option[Foo]
-        # ```
-        # returning `tyGenericInvocation` makes `Option[Foo]` to `tyGenericInvocation` and
-        # next time `semGeneric` is called with `Option[Foo]`, containsGenericType(typeof(`Foo`)) == true
-        # and `isConcrete == false`.
-        if prev == nil:
-          result = newTypeS(tyForward, c)
-          result.sym = s
-        else:
-          assignType(result, newTypeS(tyForward, c))
-          result.sym = s
-        c.forwardTypeUpdates.add (getCurrOwner(c), result, n) #fixes 1500
-        return
+      elif containsGenericInvocationWithForward(n[0]):
+        c.forwardTypeUpdates.add (result, n) #fixes 1500
       else:
         result = instGenericContainer(c, n.info, result,
                                       allowMetaTypes = false)
@@ -1897,12 +1812,6 @@ proc semTypeExpr(c: PContext, n: PNode; prev: PType): PType =
         # by macros. Only macros can summon unnamed types
         # and cast spell upon AST. Here we need to give
         # it a name taken from left hand side's node
-        if result.state == Sealed:
-          # The unnamed type was loaded from a dependency's NIF and must not
-          # be mutated in place; attach the name to a fresh copy instead.
-          let orig = result
-          result = copyType(orig, c.idgen, getCurrOwner(c))
-          copyTypeProps(c.graph, c.idgen.module, result, orig)
         result.sym = prev.sym
         result.sym.typ = result
       else:
@@ -2075,57 +1984,6 @@ proc semStaticType(c: PContext, childNode: PNode, prev: PType): PType =
   result.rawAddSon(base)
   result.incl tfHasStatic
 
-proc semTypeOfImpl(c: PContext; n: PNode): PNode =
-  var m = BiggestInt 1 # typeOfIter
-  var modifierMode = BiggestInt 0 # CompatibleTypeModifiers
-  type
-    TypeOfParams = enum
-      topMode
-      topModifier
-  if n.len in 3 .. 4:
-    for i in 2 ..< n.len:
-      var argKind = topMode
-      var arg: PNode = nil
-      if n[i].kind == nkExprEqExpr and n[i][0].kind == nkIdent:
-        # named param
-        case n[i][0].ident.s
-        of "mode": argKind = topMode
-        of "modifierMode": argKind = topModifier
-        else:
-          localError(c.config, n.info, "typeof: got unknown parameter name")
-        arg = n[i][1]
-      else:
-        if i == 2:
-          argKind = topMode
-        else:
-          argKind = topModifier
-        arg = n[i]
-      case argKind
-      of topMode:
-        let mode = semConstExpr(c, arg)
-        if mode.kind != nkIntLit:
-          localError(c.config, n.info, "typeof: cannot evaluate 'mode' parameter at compile-time")
-        else:
-          m = mode.intVal
-      of topModifier:
-        let modMode = semConstExpr(c, arg)
-        if modMode.kind != nkIntLit:
-          localError(c.config, n.info, "typeof: cannot evaluate 'modifierMode' parameter at compile-time")
-        else:
-          modifierMode = modMode.intVal
-
-  inc c.inTypeofContext
-  defer: dec c.inTypeofContext # compiles can raise an exception
-  var typExpr = semExprNoDeref(c, n[1], if m == 1: {efInTypeof} else: {})
-  if modifierMode == 0:
-    # CompatibleTypeModifiers
-    typExpr.typ = typExpr.typ.skipTypes({tyVar, tyLent})
-  elif modifierMode == 1:
-    # RemoveTypeModifiers
-    typExpr.typ = typExpr.typ.skipTypes({tyVar, tyLent, tySink})
-
-  result = typExpr
-
 proc semTypeOf(c: PContext; n: PNode; prev: PType): PType =
   openScope(c)
   inc c.inTypeofContext
@@ -2146,7 +2004,16 @@ proc semTypeOf(c: PContext; n: PNode; prev: PType): PType =
 
 proc semTypeOf2(c: PContext; n: PNode; prev: PType): PType =
   openScope(c)
-  let ex = semTypeOfImpl(c, n)
+  var m = BiggestInt 1 # typeOfIter
+  if n.len == 3:
+    let mode = semConstExpr(c, n[2])
+    if mode.kind != nkIntLit:
+      localError(c.config, n.info, "typeof: cannot evaluate 'mode' parameter at compile-time")
+    else:
+      m = mode.intVal
+  inc c.inTypeofContext
+  defer: dec c.inTypeofContext # compiles can raise an exception
+  let ex = semExprWithType(c, n[1], if m == 1: {efInTypeof} else: {})
   closeScope(c)
   result = ex.typ
   if result.kind == tyFromExpr:
@@ -2182,15 +2049,13 @@ proc semTypeIdent(c: PContext, n: PNode): PSym =
         # proc signature for example
         if c.inGenericInst > 0:
           let bound = result.typ.elementType.sym
-          # the symbol may still point to the uninstantiated generic body type 
-          if bound != nil and bound.typ == result.typ.elementType:
-            return bound
+          if bound != nil: return bound
           return result
         if result.typ.sym == nil:
           localError(c.config, n.info, errTypeExpected)
           return errorSym(c, n)
         result = result.typ.sym.copySym(c.idgen)
-        result.typ = exactReplica(result.typ, c.idgen)
+        result.typ = exactReplica(result.typ)
         result.typ.incl tfUnresolved
 
       if result.kind == skGenericParam:
@@ -2335,9 +2200,6 @@ proc semTypeNode(c: PContext, n: PNode, prev: PType): PType =
         result = semAnyRef(c, n, tyPtr, prev)
       elif op.id == ord(wRef):
         result = semAnyRef(c, n, tyRef, prev)
-      elif op.id == ord(wStatic):
-        checkSonsLen(n, 2, c.config)
-        result = semStaticType(c, n[1], prev)
       elif op.id == ord(wType):
         checkSonsLen(n, 2, c.config)
         result = semTypeOf(c, n[1], prev)
@@ -2357,8 +2219,7 @@ proc semTypeNode(c: PContext, n: PNode, prev: PType): PType =
     else:
       result = semTypeNode(c, whenResult, prev)
   of nkBracketExpr:
-    # Actually len >= 2 is required, but it doesn't print errors nicely with empty brackets
-    checkMinSonsLen(n, 1, c.config)
+    checkMinSonsLen(n, 2, c.config)
     var head = n[0]
     var s = if head.kind notin nkCallKinds: semTypeIdent(c, head)
             else: symFromExpectedTypeNode(c, semExpr(c, head))
@@ -2376,21 +2237,10 @@ proc semTypeNode(c: PContext, n: PNode, prev: PType): PType =
         incl result, tfHasAsgn
     of mVarargs: result = semVarargs(c, n, prev)
     of mTypeDesc, mType, mTypeOf:
-      if n.len != 2:
-        let name = case s.magic:
-                   of mTypeDesc: "typedesc"
-                   of mType: "type"
-                   of mTypeOf: "typeof"
-                   else: ""
-        localError(c.config, n.info, errXExpectsOneTypeParam % name)
-      else:
-        result = makeTypeDesc(c, semTypeNode(c, n[1], nil))
-        result.incl tfExplicit
+      result = makeTypeDesc(c, semTypeNode(c, n[1], nil))
+      result.incl tfExplicit
     of mStatic:
-      if n.len != 2:
-        localError(c.config, n.info, errXExpectsOneTypeParam % "static")
-      else:
-        result = semStaticType(c, n[1], prev)
+      result = semStaticType(c, n[1], prev)
     of mExpr:
       result = semTypeNode(c, n[0], nil)
       if result != nil:
@@ -2400,11 +2250,9 @@ proc semTypeNode(c: PContext, n: PNode, prev: PType): PType =
         for i in 1..<n.len:
           result.rawAddSon(semTypeNode(c, n[i], nil))
     of mDistinct:
-      checkSonsLen(n, 2, c.config)
       result = newOrPrevType(tyDistinct, prev, c)
       addSonSkipIntLit(result, semTypeNode(c, n[1], nil), c.idgen)
     of mVar:
-      checkSonsLen(n, 2, c.config)
       result = newOrPrevType(tyVar, prev, c)
       var base = semTypeNode(c, n[1], nil)
       if base.kind in {tyVar, tyLent}:
@@ -2435,7 +2283,7 @@ proc semTypeNode(c: PContext, n: PNode, prev: PType): PType =
     else:
       result = typeExpr.typ.base
       if result.isMetaType and
-         result.kind notin tyTypeClasses:
+         result.kind != tyUserTypeClass:
            # the dot expression may refer to a concept type in
            # a different module. allow a normal alias then.
         let preprocessed = semGenericStmt(c, n)
@@ -2528,7 +2376,7 @@ proc semTypeNode(c: PContext, n: PNode, prev: PType): PType =
 
       if n.kind == nkIteratorTy and result.kind == tyProc:
         result.incl(tfIterator)
-      if result.callConv == ccClosure and c.config.selectedGC in {gcArc, gcOrc, gcAtomicArc, gcYrc}:
+      if result.callConv == ccClosure and c.config.selectedGC in {gcArc, gcOrc, gcAtomicArc}:
         result.incl tfHasAsgn
   of nkEnumTy: result = semEnum(c, n, prev)
   of nkType: result = n.typ

compiler/semtypinst.nim

@@ -272,17 +272,10 @@ proc replaceTypeVarsN(cl: var TReplTypeVars, n: PNode; start=0; expectedType: PT
   if n == nil: return
   result = copyNode(n)
   if n.typ != nil:
-    var nodeTyp = n.typ
-    if nodeTyp.kind == tyFromExpr:
+    if n.typ.kind == tyFromExpr:
       # type of node should not be evaluated as a static value
-      if nodeTyp.state == Sealed:
-        # IC: do not brand the loaded shared original — a tyFromExpr is a
-        # placeholder that `replaceTypeVarsT` resolves away, so the copy
-        # carries no identity later comparisons could miss (mirrors
-        # `instantiateProcType`)
-        nodeTyp = copyType(nodeTyp, cl.c.idgen, nodeTyp.owner)
-      nodeTyp.incl tfNonConstExpr
-    result.typ = replaceTypeVarsT(cl, nodeTyp)
+      n.typ.incl tfNonConstExpr
+    result.typ = replaceTypeVarsT(cl, n.typ)
     checkMetaInvariants(cl, result.typ)
   case n.kind
   of nkNone..pred(nkSym), succ(nkSym)..nkNilLit:
@@ -380,7 +373,6 @@ proc replaceTypeVarsS(cl: var TReplTypeVars, s: PSym, t: PType): PSym =
       var g: G[string]
 
   ]#
-  # XXX FIXME This causes system.Natural to be duplicated during compilation of system.nim as cl.owner == nil!
   result = copySym(s, cl.c.idgen)
   incl(result.flagsImpl, sfFromGeneric)
   #idTablePut(cl.symMap, s, result)
@@ -394,13 +386,6 @@ proc lookupTypeVar(cl: var TReplTypeVars, t: PType): PType =
     # don't bind `auto` return type to a previous binding of `auto`
     return nil
   result = cl.typeMap.lookup(t)
-  when defined(icDbgRefc):
-    if t.kind in {tyGenericParam, tyTypeDesc}:
-      echo "[icBind] lookup ", t.kind, " ", typeToString(t), " uid=", t.uniqueId.module, ".",
-        t.uniqueId.item, " itemId=", t.itemId.module, ".", t.itemId.item,
-        " state=", t.state, " flags=", t.flags, " -> ",
-        (if result != nil: typeToString(result) else: "MISS"),
-        " allowMeta=", cl.allowMetaTypes
   if result == nil:
     if cl.allowMetaTypes or tfRetType in t.flags: return
     localError(cl.c.config, t.sym.info, "cannot instantiate: '" & typeToString(t) & "'")
@@ -415,7 +400,7 @@ proc lookupTypeVar(cl: var TReplTypeVars, t: PType): PType =
 proc instCopyType*(cl: var TReplTypeVars, t: PType): PType =
   # XXX: relying on allowMetaTypes is a kludge
   if cl.allowMetaTypes:
-    result = t.exactReplica(cl.c.idgen)
+    result = t.exactReplica
   else:
     result = copyType(t, cl.c.idgen, t.owner)
     copyTypeProps(cl.c.graph, cl.c.idgen.module, result, t)
@@ -460,13 +445,6 @@ proc handleGenericInvocation(cl: var TReplTypeVars, t: PType): PType =
         header[i] = x
         propagateToOwner(header, x)
     else:
-      # Under IC `t` may be a loaded dep type (Sealed/immutable); mutating it
-      # would assert, so propagate into a copy. For non-Sealed types keep
-      # devel's in-place propagation: unconditionally copying here changes
-      # `header != t` and with it the cached-instance lookup below, which
-      # regressed non-IC generic instantiations (arraymancer: a cached
-      # NimSeqV2 instance with stale flags was returned for a cast target).
-      if header == t and t.state == Sealed: header = instCopyType(cl, t)
       propagateToOwner(header, x)
 
   if header != t:
@@ -518,14 +496,8 @@ proc handleGenericInvocation(cl: var TReplTypeVars, t: PType): PType =
   let bbody = last body
   var newbody = replaceTypeVarsT(cl, bbody, isInstValue = true)
   cl.skipTypedesc = oldSkipTypedesc
-  let newbodyFlags = newbody.flags + (t.flags + body.flags - tfInstClearedFlags)
-  if newbody.state != Sealed:
-    newbody.flags = newbodyFlags
-  # else: `newbody` is a type loaded from a dep module (it can even be a
-  # builtin like `int` when the generic's body is computed by a macro) and is
-  # immutable under IC. Skip the in-place flag accumulation on the shared
-  # type; the instance `result` still receives the flags below.
-  result.flags = result.flags + newbodyFlags - tfInstClearedFlags
+  newbody.flags = newbody.flags + (t.flags + body.flags - tfInstClearedFlags)
+  result.flags = result.flags + newbody.flags - tfInstClearedFlags
 
   setToPreviousLayer(cl.typeMap)
 
@@ -545,11 +517,8 @@ proc handleGenericInvocation(cl: var TReplTypeVars, t: PType): PType =
       # generics *when the type is constructed*:
       cl.c.graph.setAttachedOp(cl.c.module.position, newbody, attachedDeepCopy,
           cl.c.instTypeBoundOp(cl.c, dc, result, cl.info, attachedDeepCopy, 1))
-    if newbody.typeInst == nil and newbody.state != Sealed:
+    if newbody.typeInst == nil:
       # doAssert newbody.typeInst == nil
-      # An IC-loaded (Sealed) `newbody` keeps whatever `typeInst` its defining
-      # module serialized; recording this process's first instantiation on the
-      # shared type is not possible (and was always first-wins anyway).
       newbody.typeInst = result
       if tfRefsAnonObj in newbody.flags and newbody.kind != tyGenericInst:
         # can come here for tyGenericInst too, see tests/metatype/ttypeor.nim
@@ -593,26 +562,6 @@ proc eraseVoidParams*(t: PType) =
       setLen t.n.sons, pos
       break
 
-proc eraseTupleVoidFields*(t: PType) =
-  ## Remove void fields from a named tuple type, compacting both `t.n`
-  ## (the field symbol nodes) and `t.sonsImpl` (the child types).
-  if t.n == nil: return  # anonymous tuple, nothing to compact
-  for i in 0..<t.kidsLen:
-    if t.n[i].kind == nkRecList or t[i].kind == tyVoid:
-      # found first void field, compact from here
-      var pos = i
-      for j in i+1..<t.kidsLen:
-        if t[j].kind != tyVoid and j < t.n.len and t.n[j].kind != nkRecList:
-          t.n[pos] = t.n[j]
-          t[pos] = t[j]
-          if t.n[pos].kind == nkSym:
-            t.n[pos].sym.position = pos
-          inc pos
-        # else: skip void entries
-      setLen t.n.sons, pos
-      t.setSonsLen pos
-      break
-
 proc skipIntLiteralParams*(t: PType; idgen: IdGenerator) =
   for i, p in t.ikids:
     if p == nil: continue
@@ -818,8 +767,6 @@ proc replaceTypeVarsTAux(cl: var TReplTypeVars, t: PType, isInstValue = false):
         propagateFieldFlags(result, result.n)
         if result.kind == tyObject and cl.c.computeRequiresInit(cl.c, result):
           result.incl tfRequiresInit
-        if result.kind == tyTuple:
-          eraseTupleVoidFields(result)
 
       of tyProc:
         eraseVoidParams(result)
@@ -838,11 +785,7 @@ proc replaceTypeVarsTAux(cl: var TReplTypeVars, t: PType, isInstValue = false):
       if t.kind == tyRef and t.hasElementType and t.elementType.kind == tyObject and t.elementType.n != nil:
         discard replaceObjBranches(cl, t.elementType.n)
 
-      elif result.n != nil and t.kind == tyObject and result.state != Sealed:
-        # A type loaded from the IC cache already had its object branches
-        # resolved when it was originally compiled, and must not be mutated in
-        # place (nor copied, which would break object-inheritance identity), so
-        # only non-Sealed types are processed here.
+      elif result.n != nil and t.kind == tyObject:
         # Invalidate the type size as we may alter its structure
         result.size = -1
         result.n = replaceObjBranches(cl, result.n)
@@ -894,10 +837,7 @@ proc recomputeFieldPositions*(t: PType; obj: PNode; currPosition: var int) =
     for i in 1..<obj.len:
       recomputeFieldPositions(nil, lastSon(obj[i]), currPosition)
   of nkSym:
-    # A field loaded from the IC cache is already at its final position and must
-    # not be mutated; only freshly instantiated fields need (re)positioning.
-    if obj.sym.state != Sealed:
-      obj.sym.position = currPosition
+    obj.sym.position = currPosition
     inc currPosition
   else: discard "cannot happen"
 

compiler/sighashes.nim

@@ -41,7 +41,6 @@ type
     CoType
     CoOwnerSig
     CoIgnoreRange
-    CoIgnoreRangeInArray
     CoConsiderOwned
     CoDistinct
     CoHashTypeInsideNode
@@ -52,17 +51,7 @@ proc hashSym(c: var MD5Context, s: PSym) =
     c &= ":anon"
   else:
     var it = s
-    when defined(icDbgHash):
-      var ownerSteps = 0
     while it != nil:
-      when defined(icDbgHash):
-        inc ownerSteps
-        if ownerSteps >= 1000 and ownerSteps <= 1030:
-          echo "OWNERLOOP(hashSym) n=", ownerSteps, " sym=", it.name.s, " kind=", it.kind,
-            " id=", it.itemId, " flags=", it.flags, " state=", it.state,
-            " start=", s.name.s, " startId=", s.itemId
-        elif ownerSteps == 1031:
-          raiseAssert "owner-chain cycle detected, see OWNERLOOP dump above"
       c &= it.name.s
       c &= "."
       it = it.owner
@@ -75,17 +64,7 @@ proc hashTypeSym(c: var MD5Context, s: PSym; conf: ConfigRef) =
   else:
     var it = s
     c &= customPath(conf.toFullPath(s.info))
-    when defined(icDbgHash):
-      var ownerSteps = 0
     while it != nil:
-      when defined(icDbgHash):
-        inc ownerSteps
-        if ownerSteps >= 1000 and ownerSteps <= 1030:
-          echo "OWNERLOOP n=", ownerSteps, " sym=", it.name.s, " kind=", it.kind,
-            " id=", it.itemId, " flags=", it.flags, " state=", it.state,
-            " start=", s.name.s, " startId=", s.itemId
-        elif ownerSteps == 1031:
-          raiseAssert "owner-chain cycle detected, see OWNERLOOP dump above"
       if sfFromGeneric in it.flags and it.kind in routineKinds and
           it.typ != nil:
         hashType c, it.typ, {CoProc}, conf
@@ -122,44 +101,15 @@ proc hashTree(c: var MD5Context, n: PNode; flags: set[ConsiderFlag]; conf: Confi
   else:
     for i in 0..<n.len: hashTree(c, n[i], flags, conf)
 
-when defined(icDbgHash):
-  var hashDepth = 0
-  var hashCalls = 0
-  var hashMaxDepth = 0
-
 proc hashType(c: var MD5Context, t: PType; flags: set[ConsiderFlag]; conf: ConfigRef) =
   if t == nil:
     c &= "\254"
     return
-  when defined(icDbgHash):
-    inc hashDepth
-    inc hashCalls
-    if hashDepth > hashMaxDepth: hashMaxDepth = hashDepth
-    if hashCalls >= 500_000_000 and hashCalls <= 500_000_300:
-      echo "HASHLOOP n=", hashCalls, " d=", hashDepth, " kind=", t.kind, " id=", t.itemId,
-        " uniq=", t.uniqueId, " sym=", (if t.sym != nil: t.sym.name.s else: "NIL"),
-        " state=", t.state, " owner=", (if t.owner != nil: t.owner.name.s else: "NIL")
-    elif hashCalls == 500_000_301:
-      echo "HASHLOOP maxDepth=", hashMaxDepth
-      raiseAssert "hashType runaway detected, see HASHLOOP dump above"
-    defer:
-      dec hashDepth
 
   # Ensure type is fully loaded before hashing to avoid hash changing
   # as properties are accessed and trigger lazy loading.
   backendEnsureMutable(t)
 
-  # Bare type-class keywords used as a typedesc without arguments (e.g. `array`,
-  # `range`, `distinct` passed to `signatureHash`) have no children, so the
-  # structural branches below would index a non-existent `elementType`. Hash them
-  # by kind (+ sym for an extra, stable distinction) — enough for a stable,
-  # distinct identity. (`seq`/`openArray`/`tuple` already fall through the empty
-  # `else` loop unharmed; this covers the branches that index `elementType`.)
-  if t.kind in {tyArray, tyRange, tyDistinct} and not t.hasElementType:
-    c &= char(t.kind)
-    if t.sym != nil: c.hashSym(t.sym)
-    return
-
   case t.kind
   of tyGenericInvocation:
     for a in t.kids:
@@ -204,7 +154,7 @@ proc hashType(c: var MD5Context, t: PType; flags: set[ConsiderFlag]; conf: Confi
       assert inst.kind == tyGenericInst
       c.hashType inst.genericHead, flags, conf
       for _, a in inst.genericInstParams:
-        c.hashType a, flags+{CoDistinct}, conf
+        c.hashType a, flags, conf
       t.typeInstImpl = inst
       return
     c &= char(t.kind)
@@ -270,17 +220,10 @@ proc hashType(c: var MD5Context, t: PType; flags: set[ConsiderFlag]; conf: Confi
     else:
       for a in t.kids: c.hashType a, flags+{CoIgnoreRange}, conf
   of tyRange:
-    if {CoIgnoreRange, CoIgnoreRangeInArray} * flags == {}:
+    if CoIgnoreRange notin flags:
       c &= char(t.kind)
       c.hashTree(t.n, {}, conf)
-      c.hashType(t.elementType, flags, conf)
-    elif CoIgnoreRangeInArray in flags:
-      # include only the length of the range (not its specific bounds)
-      c &= char(t.kind)
-      let l = lengthOrd(conf, t)
-      lowlevel l
-    else:
-      c.hashType(t.elementType, flags, conf)
+    c.hashType(t.elementType, flags, conf)
   of tyStatic:
     c &= char(t.kind)
     c.hashTree(t.n, {}, conf)
@@ -297,29 +240,6 @@ proc hashType(c: var MD5Context, t: PType; flags: set[ConsiderFlag]; conf: Confi
         c.hashType(param.typ, flags, conf)
         c &= ','
       c.hashType(t.returnType, flags, conf)
-    elif t.n != nil and t.n.kind == nkFormalParams:
-      # Under IC a loaded proc type stores its parameters only in `n`; `sons`
-      # holds just the return type. Hashing `t.signature` would silently drop
-      # every parameter, collapsing distinct proc types onto one hash, so the
-      # same logical type got different C struct names in different TUs
-      # ("incompatible type for argument" on closure args). Hash the return
-      # type first and then the parameter types from `n` — for from-source
-      # types `n`'s param types equal `sons[1..]`, so non-IC hashes are
-      # unchanged. (Same fix as typekeys' tyProc branch.)
-      c.hashType(t.returnType, flags, conf)
-      for i in 1..<t.n.len:
-        let p = t.n[i]
-        if p.kind == nkSym:
-          backendEnsureMutable(p.sym)
-          # The hidden closure env param: under IC, lambda lifting shares the
-          # routine's AST params with `typ.n`, so the lifted `:envP` leaks into
-          # the TYPE's params (from-source types never carry it). It is not part
-          # of the type's identity — `genProcParams` skips it the same way.
-          if t.callConv == ccClosure and p.sym.name.s == ":envP":
-            continue
-          c.hashType(p.sym.typ, flags, conf)
-        else:
-          c.hashType(p.typ, flags, conf)
     else:
       for a in t.signature: c.hashType(a, flags, conf)
     c &= char(t.callConv)
@@ -333,23 +253,8 @@ proc hashType(c: var MD5Context, t: PType; flags: set[ConsiderFlag]; conf: Confi
     if tfVarargs in t.flags: c &= ".varargs"
   of tyArray:
     c &= char(t.kind)
-    c.hashType(t.indexType, flags-{CoIgnoreRange}+{CoIgnoreRangeInArray}, conf)
+    c.hashType(t.indexType, flags-{CoIgnoreRange}, conf)
     c.hashType(t.elementType, flags-{CoIgnoreRange}, conf)
-  of tyBuiltInTypeClass:
-    # A builtin type class (`object`, `tuple`, `proc`, `ref`, `seq`, ...) is
-    # identified solely by the *kind* of its single placeholder son plus a few
-    # flags/callConv (see `sameType`). That son is a fresh, field-less, sym-less
-    # type, so the generic `else` below would recurse into it and hash its
-    # process-local `t.id` — unstable across the NIF boundary. nim-serialization
-    # keys auto-serialization on `signatureHash(object)`/`tuple`/... and missed
-    # under IC because the registering and consuming modules minted different
-    # placeholder ids. Hash the class identity that `sameType` actually compares.
-    c &= char(t.kind)
-    let elem = t.elementType
-    c &= char(elem.kind)
-    for f in eqTypeFlags * elem.flags: c &= char(ord(f))
-    if elem.kind == tyProc and tfExplicitCallConv in elem.flags:
-      c &= char(elem.callConv)
   else:
     c &= char(t.kind)
     for a in t.kids: c.hashType(a, flags, conf)

compiler/sigmatch.nim

@@ -46,8 +46,7 @@ type
 
   TCandidate* = object
     c*: PContext
-    exactMatches*: int
-    iteratorPreference*: int # prefer iterators in iterator-oriented contexts
+    exactMatches*: int       # also misused to prefer iters over procs
     genericMatches: int      # also misused to prefer constraints
     subtypeMatches: int
     intConvMatches: int      # conversions to int are not as expensive
@@ -111,8 +110,7 @@ proc markOwnerModuleAsUsed*(c: PContext; s: PSym)
 proc initCandidateAux(ctx: PContext,
                       callee: PType): TCandidate {.inline.} =
   result = TCandidate(c: ctx, exactMatches: 0, subtypeMatches: 0,
-                      iteratorPreference: 0, convMatches: 0, intConvMatches: 0,
-                      genericMatches: 0,
+                      convMatches: 0, intConvMatches: 0, genericMatches: 0,
                       state: csEmpty, firstMismatch: MismatchInfo(),
                       callee: callee, call: nil, baseTypeMatch: false,
                       genericConverter: false, inheritancePenalty: -1
@@ -135,11 +133,6 @@ proc put(c: var TCandidate, key, val: PType) {.inline.} =
         writeStackTrace()
     if c.c.module.name.s == "temp3":
       echo "binding ", key, " -> ", val
-  when defined(icDbgRefc):
-    if key.kind in {tyGenericParam, tyTypeDesc}:
-      echo "[icBind] put ", key.kind, " ", typeToString(key), " uid=", key.uniqueId.module, ".",
-        key.uniqueId.item, " itemId=", key.itemId.module, ".", key.itemId.item,
-        " state=", key.state, " -> ", typeToString(val)
   put(c.bindings, key, val.skipIntLit(c.c.idgen))
 
 proc typeRel*(c: var TCandidate, f, aOrig: PType,
@@ -167,7 +160,8 @@ proc matchGenericParam(m: var TCandidate, formal: PType, n: PNode) =
       arg = newTypeS(tyStatic, m.c, son = evaluated.typ)
       arg.n = evaluated
   elif formalBase.kind == tyTypeDesc:
-    discard # if arg is not tyTypeDesc, typeRel will report the mismatch
+    if arg.kind != tyTypeDesc:
+      arg = makeTypeDesc(m.c, arg)
   else:
     arg = arg.skipTypes({tyTypeDesc})
   let tm = typeRel(m, formal, arg)
@@ -400,7 +394,6 @@ proc complexDisambiguation(a, b: PType): int =
 proc writeMatches*(c: TCandidate) =
   echo "Candidate '", c.calleeSym.name.s, "' at ", c.c.config $ c.calleeSym.info
   echo "  exact matches: ", c.exactMatches
-  echo "  iterator preference: ", c.iteratorPreference
   echo "  generic matches: ", c.genericMatches
   echo "  subtype matches: ", c.subtypeMatches
   echo "  intconv matches: ", c.intConvMatches
@@ -419,8 +412,6 @@ proc cmpInheritancePenalty(a, b: int): int =
 proc cmpCandidates*(a, b: TCandidate, isFormal=true): int =
   result = a.exactMatches - b.exactMatches
   if result != 0: return
-  result = a.iteratorPreference - b.iteratorPreference
-  if result != 0: return
   result = a.genericMatches - b.genericMatches
   if result != 0: return
   result = a.subtypeMatches - b.subtypeMatches
@@ -624,8 +615,6 @@ proc isGenericObjectOf(f, a: PType): bool =
   # use sym equality to check if the `tyGenericBody` types are equal
   result = aRoot != nil and f.sym == aRoot.sym
 
-
-
 proc isObjectSubtype(c: var TCandidate; a, f, fGenericOrigin: PType): int =
   var t = a
   assert t.kind == tyObject
@@ -789,19 +778,6 @@ proc procParamTypeRel(c: var TCandidate; f, a: PType): TTypeRelation =
     # if f is metatype.
     result = typeRel(c, f, a)
 
-  if result == isEqual and
-      procParamTypeBackendAliases notin c.c.config.legacyFeatures:
-    # Ensure types that are semantically equal also match at the backend level.
-    # E.g. reject assigning proc(csize_t) to proc(uint) since these map to
-    # different C types (size_t vs unsigned long long).
-    let fCheck = concreteType(c, f)
-    let aCheck = concreteType(c, a)
-    # Note that `result` is equal; now check whether they have the same
-    # backend type.
-    if fCheck != nil and aCheck != nil and
-      not sameBackendTypePickyAliases(fCheck, aCheck, {IgnoreFlags}):
-      result = isNone
-
   if result <= isSubrange or inconsistentVarTypes(f, a):
     result = isNone
 
@@ -916,7 +892,7 @@ proc matchUserTypeClass*(m: var TCandidate; ff, a: PType): PType =
         case typ.kind
         of tyStatic:
           param = paramSym skConst
-          param.typ = typ.exactReplica(m.c.idgen)
+          param.typ = typ.exactReplica
           #copyType(typ, c.idgen, typ.owner)
           if typ.n == nil:
             param.typ.incl tfInferrableStatic
@@ -924,7 +900,7 @@ proc matchUserTypeClass*(m: var TCandidate; ff, a: PType): PType =
             param.ast = typ.n
         of tyFromExpr:
           param = paramSym skVar
-          param.typ = typ.exactReplica(m.c.idgen)
+          param.typ = typ.exactReplica
           #copyType(typ, c.idgen, typ.owner)
         else:
           param = paramSym skType
@@ -977,7 +953,7 @@ proc matchUserTypeClass*(m: var TCandidate; ff, a: PType): PType =
   if ff.kind == tyUserTypeClassInst:
     result = generateTypeInstance(c, m.bindings, typeClass.sym.info, ff)
   else:
-    result = ff.exactReplica(m.c.idgen)
+    result = ff.exactReplica
     #copyType(ff, c.idgen, ff.owner)
 
   result.n = checkedBody
@@ -1173,10 +1149,6 @@ proc enterConceptMatch(c: var TCandidate; f,a: PType, flags: TTypeRelFlags): TTy
   if concpt.kind != tyConcept:
     container = concpt
     concpt = container.reduceToBase
-  # considerPreviousT-like behavior
-  let prev = lookup(c.bindings, concpt)
-  if prev != nil:
-    return typeRel(c, prev, a, flags)
   if trDontBind in flags:
     conceptFlags.incl mfDontBind
   if trCheckGeneric in flags:
@@ -1704,6 +1676,7 @@ proc typeRel(c: var TCandidate, f, aOrig: PType,
     elif a.kind == tyGenericInst:
       if roota.base == rootf.base:
         let nextFlags = flags + {trNoCovariance}
+        var hasCovariance = false
         # YYYY
         result = isEqual
 
@@ -1715,7 +1688,7 @@ proc typeRel(c: var TCandidate, f, aOrig: PType,
           if res notin {isEqual, isGeneric}:
             if trNoCovariance notin flags and ff.kind == aa.kind:
               let paramFlags = rootf.base[i-1].flags
-              let hasCovariance =
+              hasCovariance =
                 if tfCovariant in paramFlags:
                   if tfWeakCovariant in paramFlags:
                     isCovariantPtr(c, ff, aa)
@@ -1726,36 +1699,35 @@ proc typeRel(c: var TCandidate, f, aOrig: PType,
                     typeRel(c, aa, ff, flags) == isSubtype
               if hasCovariance:
                 continue
-            result = isNone
-            break
 
-        if result != isNone:
-          if prev == nil: put(c, f, a)
+            return isNone
+        if prev == nil: put(c, f, a)
+      else:
+        let fKind = rootf.last.kind
+        if fKind in {tyAnd, tyOr}:
+          result = typeRel(c, last(f), a, flags)
+          if result != isNone: put(c, f, a)
           return
 
-      let fKind = rootf.last.kind
-      if fKind in {tyAnd, tyOr}:
-        result = typeRel(c, last(f), a, flags)
-        if result != isNone: put(c, f, a)
-        return
+        var aAsObject = roota.last
 
-      var aAsObject = roota.last
+        if fKind in {tyRef, tyPtr}:
+          if aAsObject.kind == tyObject:
+            # bug #7600, tyObject cannot be passed
+            # as argument to tyRef/tyPtr
+            return isNone
+          elif aAsObject.kind == fKind:
+            aAsObject = aAsObject.base
 
-      if fKind in {tyRef, tyPtr}:
-        if aAsObject.kind == tyObject:
-          # bug #7600, tyObject cannot be passed
-          # as argument to tyRef/tyPtr
-          return isNone
-        elif aAsObject.kind == fKind:
-          aAsObject = aAsObject.base
+        if aAsObject.kind == tyObject and trIsOutParam notin flags:
+          let baseType = aAsObject.base
+          if baseType != nil:
+            if tfFinal notin aAsObject.flags:
+              inc c.inheritancePenalty, 1 + int(c.inheritancePenalty < 0)
+            let ret = typeRel(c, f, baseType, flags)
+            return if ret in {isEqual,isGeneric}: isSubtype else: ret
 
-      if aAsObject.kind == tyObject and trIsOutParam notin flags:
-        let baseType = aAsObject.base
-        if baseType != nil:
-          if tfFinal notin aAsObject.flags:
-            inc c.inheritancePenalty, 1 + int(c.inheritancePenalty < 0)
-          let ret = typeRel(c, f, baseType, flags)
-          return if ret in {isEqual,isGeneric}: isSubtype else: ret
+        result = isNone
     else:
       assert last(origF) != nil
       result = typeRel(c, last(origF), a, flags)
@@ -1768,21 +1740,6 @@ proc typeRel(c: var TCandidate, f, aOrig: PType,
       let ff = last(f)
       if ff != nil:
         result = typeRel(c, ff, a, flags)
-      if result == isNone and a.kind == tyGenericInst and trBindGenericParam in flags:
-        var depth = -1
-        # Generic-parameter constraints like `F: Future` can miss in `last(f)`
-        # when the actual type inherits from a concrete generic instantiation.
-        # Keep this fallback scoped to generic-parameter matching so typedesc
-        # overloads such as `type Future[T]` still prefer more specific
-        # descendants like `InternalRaisesFuture[T, E]`.
-        if isGenericSubtype(c, a, f, depth, f) and depth > 0:
-          var askip = skippedNone
-          let aobj = a.skipToObject(askip)
-          if aobj != nil and tfFinal notin aobj.flags:
-            # Keep overload ranking consistent with other inheritance-based
-            # matches: deeper descendants are slightly worse candidates.
-            inc c.inheritancePenalty, depth + int(c.inheritancePenalty < 0)
-          result = isGeneric
   of tyGenericInvocation:
     var x = a.skipGenericAlias
     if x.kind == tyGenericParam and x.len > 0:
@@ -2227,9 +2184,9 @@ proc implicitConv(kind: TNodeKind, f: PType, arg: PNode, m: TCandidate,
       result.typ = errorType(c)
   else:
     result.typ = f.skipTypes({tySink})
-  # keep varness, but don't wrap lent types with var
+  # keep varness
   if arg.typ != nil and arg.typ.kind == tyVar:
-    result.typ = toVar(result.typ.skipTypes({tyLent}), tyVar, c.idgen)
+    result.typ = toVar(result.typ, tyVar, c.idgen)
     # copy the tfVarIsPtr flag
     result.typ.flags = arg.typ.flags
   else:
@@ -2497,10 +2454,6 @@ proc paramTypesMatchAux(m: var TCandidate, f, a: PType,
       return arg
     elif f.kind == tyStatic and arg.typ.n != nil:
       return arg.typ.n
-    elif f.kind == tyUntyped:
-      # bug #25693: a different overload candidate may have sem-checked the
-      # operand and left symbols behind; templates expect the pristine AST.
-      return argOrig
     else:
       return argSemantized # argOrig
 
@@ -2675,7 +2628,7 @@ proc staticAwareTypeRel(m: var TCandidate, f: PType, arg: var PNode): TTypeRelat
     # The ast of the type does not point to the symbol.
     # Without this we will never resolve a `static proc` with overloads
     let copiedNode = copyNode(arg)
-    copiedNode.typ = exactReplica(copiedNode.typ, m.c.idgen)
+    copiedNode.typ = exactReplica(copiedNode.typ)
     copiedNode.typ.n = arg
     arg = copiedNode
   typeRel(m, f, arg.typ)
@@ -2794,8 +2747,7 @@ proc prepareOperand(c: PContext; formal: PType; a: PNode, newlyTyped: var bool):
     result = a
   elif a.typ.isNil:
     if formal.kind == tyIterable:
-      let flags = {efDetermineType, efAllowStmt, efWantIterator, efWantIterable,
-                   efPreferIteratorForIterable}
+      let flags = {efDetermineType, efAllowStmt, efWantIterator, efWantIterable}
       result = c.semOperand(c, a, flags)
     else:
       # XXX This is unsound! 'formal' can differ from overloaded routine to
@@ -2812,20 +2764,6 @@ proc prepareOperand(c: PContext; formal: PType; a: PNode, newlyTyped: var bool):
     considerGenSyms(c, result)
     if result.kind != nkHiddenDeref and result.typ.kind in {tyVar, tyLent} and c.matchedConcept == nil:
       result = newDeref(result)
-    # Recovery for calls resolved too early as non-iterators.
-    # TODO: retry only skIterator overloads instead of re-semming,
-    # or preserve iterator-candidates info from the earlier semcheck.
-    if formal.kind == tyIterable and result.typ.kind != tyIterable and
-        a.kind in nkCallKinds and a[0].kind in {nkIdent, nkAccQuoted, nkSym, nkOpenSym}:
-      let recheck = copyTree(a)
-      recheck.typ = nil
-      if recheck[0].kind == nkSym and recheck[0].sym != nil:
-        recheck[0] = newIdentNode(recheck[0].sym.name, recheck[0].info)
-      let flags = {efDetermineType, efAllowStmt, efNoUndeclared,
-                   efWantIterator, efWantIterable, efPreferIteratorForIterable}
-      let fresh = c.semOperand(c, recheck, flags)
-      if fresh.typ != nil and fresh.typ.kind == tyIterable:
-        return fresh
 
 proc prepareOperand(c: PContext; a: PNode, newlyTyped: var bool): PNode =
   if a.typ.isNil:
@@ -2875,12 +2813,9 @@ proc findFirstArgBlock(m: var TCandidate, n: PNode): int =
     else: break
 
 proc matchesAux(c: PContext, n, nOrig: PNode, m: var TCandidate, marker: var IntSet) =
+
   template noMatch() =
-    if m.calleeSym != nil and m.calleeSym.kind notin {skTemplate, skMacro}:
-      c.mergeShadowScope
-    else:
-      c.rememberShadowDefs
-      c.closeShadowScope
+    c.mergeShadowScope #merge so that we don't have to resem for later overloads
     m.state = csNoMatch
     m.firstMismatch.arg = a
     m.firstMismatch.formal = formal
@@ -2936,10 +2871,7 @@ proc matchesAux(c: PContext, n, nOrig: PNode, m: var TCandidate, marker: var Int
           setSon(m.call, formal.position + 1, container)
         else:
           incrIndexType(container.typ)
-        # bug #25693: like the scalar `tyUntyped` case in `paramTypesMatchAux`,
-        # a previous overload candidate may have sem-checked the operand in
-        # place; templates/macros expect the pristine AST, so use `nOrig`.
-        container.add nOrig[a]
+        container.add n[a]
     elif n[a].kind == nkExprEqExpr:
       # named param
       m.firstMismatch.kind = kUnknownNamedParam
@@ -3038,8 +2970,7 @@ proc matchesAux(c: PContext, n, nOrig: PNode, m: var TCandidate, marker: var Int
             setSon(m.call, formal.position + 1, container)
           else:
             incrIndexType(container.typ)
-          # bug #25693: see the leading isVarargsUntyped branch above.
-          container.add nOrig[a]
+          container.add n[a]
         else:
           m.baseTypeMatch = false
           m.typedescMatched = false
@@ -3091,7 +3022,6 @@ proc matchesAux(c: PContext, n, nOrig: PNode, m: var TCandidate, marker: var Int
     if m.state == csMatch and not (m.calleeSym != nil and m.calleeSym.kind in {skTemplate, skMacro}):
       c.mergeShadowScope
     else:
-      c.rememberShadowDefs
       c.closeShadowScope
 
     inc a
@@ -3162,7 +3092,6 @@ proc matches*(c: PContext, n, nOrig: PNode, m: var TCandidate) =
             put(m, formal.typ, defaultValue.typ)
         defaultValue.flags.incl nfDefaultParam
         setSon(m.call, formal.position + 1, defaultValue)
-
   # forget all inferred types if the overload matching failed
   if m.state == csNoMatch:
     for t in m.inferredTypes:

compiler/sizealignoffsetimpl.nim

@@ -394,10 +394,9 @@ proc computeSizeAlign(conf: ConfigRef; typ: PType) =
           accum.offset = 1
         computeObjectOffsetsFoldFunction(conf, typ.n, false, accum)
       let paddingAtEnd = int16(accum.finish())
-      if (typ.sym != nil and
-          typ.sym.flags * {sfCompilerProc, sfImportc} == {sfImportc} and
-          tfCompleteStruct notin typ.flags) or
-         tfIncompleteStruct in typ.flags:
+      if typ.sym != nil and
+         typ.sym.flags * {sfCompilerProc, sfImportc} == {sfImportc} and
+         tfCompleteStruct notin typ.flags:
         typ.size = szUnknownSize
         typ.align = szUnknownSize
         typ.paddingAtEnd = szUnknownSize

compiler/spawn.nim

@@ -10,7 +10,7 @@
 ## This module implements threadpool's ``spawn``.
 
 import ast, types, idents, magicsys, msgs, options, modulegraphs,
-  lowerings, liftdestructors, renderer, trees
+  lowerings, liftdestructors, renderer
 from trees import getMagic, getRoot
 
 proc callProc(a: PNode): PNode =
@@ -37,7 +37,7 @@ proc spawnResult*(t: PType; inParallel: bool): TSpawnResult =
   else: srFlowVar
 
 proc flowVarKind(c: ConfigRef, t: PType): TFlowVarKind =
-  if c.selectedGC in {gcArc, gcOrc, gcAtomicArc, gcYrc}: fvBlob
+  if c.selectedGC in {gcArc, gcOrc, gcAtomicArc}: fvBlob
   elif t.skipTypes(abstractInst).kind in {tyRef, tyString, tySequence}: fvGC
   elif containsGarbageCollectedRef(t): fvInvalid
   else: fvBlob
@@ -53,24 +53,6 @@ proc typeNeedsNoDeepCopy(t: PType): bool =
   if t.kind in {tyVar, tyLent, tySequence}: t = t.elementType
   result = not containsGarbageCollectedRef(t)
 
-proc newSpawnMoveStmt(g: ModuleGraph; idgen: IdGenerator; le, ri: PNode): PNode =
-  let op = getAttachedOp(g, ri.typ.skipTypes({tyGenericInst, tyAlias, tyVar, tySink}), attachedWasMoved)
-  if op != nil and sfOverridden in op.flags:
-    result = newNodeI(nkStmtList, le.info)
-    result.add newFastAsgnStmt(le, ri)
-
-    let wasMovedCall = newNodeI(nkCall, ri.info)
-    wasMovedCall.add newSymNode(op)
-    
-    if op.typ != nil and op.typ.signatureLen > 1 and op.typ.firstParamType.kind != tyVar:
-      wasMovedCall.add ri.skipAddr
-    else:
-      wasMovedCall.add makeAddr(ri.skipAddr, idgen)
-    
-    result.add wasMovedCall
-  else:
-    result = newFastMoveStmt(g, le, ri)
-
 proc addLocalVar(g: ModuleGraph; varSection, varInit: PNode; idgen: IdGenerator; owner: PSym; typ: PType;
                  v: PNode; useShallowCopy=false): PSym =
   result = newSym(skTemp, getIdent(g.cache, genPrefix), idgen, owner, varSection.info,
@@ -84,12 +66,12 @@ proc addLocalVar(g: ModuleGraph; varSection, varInit: PNode; idgen: IdGenerator;
   vpart[2] = if varInit.isNil: v else: vpart[1]
   varSection.add vpart
   if varInit != nil:
-    if g.config.selectedGC in {gcArc, gcOrc, gcAtomicArc, gcYrc}:
+    if g.config.selectedGC in {gcArc, gcOrc, gcAtomicArc}:
       # inject destructors pass will do its own analysis
-      varInit.add newSpawnMoveStmt(g, idgen, newSymNode(result), v)
+      varInit.add newFastMoveStmt(g, newSymNode(result), v)
     else:
       if useShallowCopy and typeNeedsNoDeepCopy(typ) or optTinyRtti in g.config.globalOptions:
-        varInit.add newSpawnMoveStmt(g, idgen, newSymNode(result), v)
+        varInit.add newFastMoveStmt(g, newSymNode(result), v)
       else:
         let deepCopyCall = newNodeI(nkCall, varInit.info, 3)
         deepCopyCall[0] = newSymNode(getSysMagic(g, varSection.info, "deepCopy", mDeepCopy))

compiler/transf.nim

@@ -22,7 +22,7 @@ import std / tables
 
 import
   options, ast, astalgo, trees, msgs,
-  idents, renderer, types, semfold, magicsys, cgmeth, parampatterns,
+  idents, renderer, types, semfold, magicsys, cgmeth,
   lowerings, liftlocals,
   modulegraphs, lineinfos
 
@@ -90,21 +90,11 @@ proc getCurrOwner(c: PTransf): PSym =
   if c.transCon != nil: result = c.transCon.owner
   else: result = c.module
 
-proc freshOwnedSym(c: PTransf; s, owner: PSym): PNode =
-  # We need to copy the symbol here because we might need to change its owner and
-  # we don't want to mess with the original symbol which might be used in other places.
-  # This can happen for example for iterators which are transformed multiple times when
-  # they are used in different contexts.
-  var fresh = copySym(s, c.idgen)
-  if fresh.kind notin routineKinds:
-    incl(fresh.flagsImpl, sfFromGeneric)
-  setOwner(fresh, owner)
-  result = newSymNode(fresh)
-
 proc newTemp(c: PTransf, typ: PType, info: TLineInfo): PNode =
   let r = newSym(skTemp, getIdent(c.graph.cache, genPrefix), c.idgen, getCurrOwner(c), info)
   r.typ = typ #skipTypes(typ, {tyGenericInst, tyAlias, tySink})
   incl(r.flagsImpl, sfFromGeneric)
+  let owner = getCurrOwner(c)
   result = newSymNode(r)
 
 proc transform(c: PTransf, n: PNode, noConstFold = false): PNode
@@ -128,24 +118,6 @@ proc newAsgnStmt(c: PTransf, kind: TNodeKind, le: PNode, ri: PNode; isFirstWrite
     le.flags.incl nfFirstWrite
   result[1] = ri
 
-proc resolveBorrowedRoutineSym(c: PTransf; s: PSym; info: TLineInfo): PSym =
-  # Follow borrow aliases to the underlying implementation symbol.
-  var s = s
-  while true:
-    # Skips over all borrowed procs getting the last proc symbol without an implementation
-    let body = getBody(c.graph, s)
-    if body.kind == nkSym and sfBorrow in body.sym.flags and getBody(c.graph, body.sym).kind == nkSym:
-      s = body.sym
-    else:
-      break
-
-  let body = getBody(c.graph, s)
-  if body.kind == nkSym:
-    result = body.sym
-  else:
-    result = nil
-    internalError(c.graph.config, info, "wrong AST for borrowed symbol")
-
 proc transformSymAux(c: PTransf, n: PNode): PNode =
   let s = n.sym
   if s.typ != nil and s.typ.callConv == ccClosure:
@@ -164,7 +136,17 @@ proc transformSymAux(c: PTransf, n: PNode): PNode =
   var tc = c.transCon
   if sfBorrow in s.flags and s.kind in routineKinds:
     # simply exchange the symbol:
-    b = newSymNode(resolveBorrowedRoutineSym(c, s, n.info), n.info)
+    var s = s
+    while true:
+      # Skips over all borrowed procs getting the last proc symbol without an implementation
+      let body = getBody(c.graph, s)
+      if body.kind == nkSym and sfBorrow in body.sym.flags and getBody(c.graph, body.sym).kind == nkSym:
+        s = body.sym
+      else:
+        break
+    b = getBody(c.graph, s)
+    if b.kind != nkSym: internalError(c.graph.config, n.info, "wrong AST for borrowed symbol")
+    b = newSymNode(b.sym, n.info)
   elif c.inlining > 0:
     # see bug #13596: we use ref-based equality in the DFA for destruction
     # injections so we need to ensure unique nodes after iterator inlining
@@ -195,39 +177,11 @@ proc transformSym(c: PTransf, n: PNode): PNode =
   result = transformSymAux(c, n)
 
 proc freshVar(c: PTransf; v: PSym): PNode =
-  result = freshOwnedSym(c, v, getCurrOwner(c))
-
-proc introduceNewRoutineHeaderSyms(c: PTransf; n: PNode; oldOwner, newOwner: PSym) =
-  # We need to introduce new symbols for the parameters and result of a routine when
-  # we copy it for inlining or closure generation.
-  # Otherwise, we would have multiple nodes referring to the same parameter symbols which
-  # can lead to problems when we need to change the owner of these symbols.
-  case n.kind
-  of nkSym:
-    if n.sym.owner == oldOwner:
-      c.transCon.mapping[n.sym.itemId] = freshOwnedSym(c, n.sym, newOwner)
-  of nkEmpty..pred(nkSym), succ(nkSym)..nkNilLit:
-    discard
-  else:
-    for i in 0..<n.len:
-      introduceNewRoutineHeaderSyms(c, n[i], oldOwner, newOwner)
-
-proc copyRoutineTypeHeader(c: PTransf; oldProc, newProc: PSym) =
-  # We need to copy the routine type header to ensure that
-  # modifications to the newProc do not affect the oldProc.
-  if oldProc.typ != nil and oldProc.typ.kind == tyProc and oldProc.typ.n != nil:
-    newProc.typ = copyType(oldProc.typ, c.idgen, newProc)
-    newProc.typ.n = newNodeI(oldProc.typ.n.kind, oldProc.typ.n.info)
-    if oldProc.typ.n.len > 0:
-      newProc.typ.n.add copyTree(oldProc.typ.n[0])
-      for i in 1..<oldProc.typ.n.len:
-        let oldParam = oldProc.typ.n[i].sym
-        var newParam = getOrDefault(c.transCon.mapping, oldParam.itemId)
-        if newParam == nil:
-          newParam = freshOwnedSym(c, oldParam, newProc)
-          c.transCon.mapping[oldParam.itemId] = newParam
-        doAssert newParam.kind == nkSym
-        newProc.typ.addParam newParam.sym
+  let owner = getCurrOwner(c)
+  var newVar = copySym(v, c.idgen)
+  incl(newVar.flagsImpl, sfFromGeneric)
+  setOwner(newVar, owner)
+  result = newSymNode(newVar)
 
 proc transformVarSection(c: PTransf, v: PNode): PNode =
   result = newTransNode(v)
@@ -374,20 +328,13 @@ proc introduceNewLocalVars(c: PTransf, n: PNode): PNode =
     if a.kind == nkSym:
       n[1] = transformSymAux(c, a)
     return n
-  of nkLambdaKinds, nkProcDef, nkFuncDef, nkMethodDef, nkConverterDef: # todo optimize nosideeffects?
+  of nkProcDef, nkFuncDef, nkMethodDef, nkConverterDef: # todo optimize nosideeffects?
     result = newTransNode(n)
-    let oldProc = n[namePos].sym
-    let x = freshOwnedSym(c, oldProc, oldProc.owner)
-    c.transCon.mapping[oldProc.itemId] = x
-    introduceNewRoutineHeaderSyms(c, n[paramsPos], oldProc, x.sym)
-    if resultPos < n.len and n[resultPos] != nil:
-      introduceNewRoutineHeaderSyms(c, n[resultPos], oldProc, x.sym)
-    copyRoutineTypeHeader(c, oldProc, x.sym)
+    let x = newSymNode(copySym(n[namePos].sym, c.idgen))
+    c.transCon.mapping[n[namePos].sym.itemId] = x
     result[namePos] = x # we have to copy proc definitions for iters
     for i in 1..<n.len:
       result[i] = introduceNewLocalVars(c, n[i])
-    if x.sym.typ != nil and x.sym.typ.kind == tyProc:
-      result[paramsPos] = x.sym.typ.n
     result[namePos].sym.ast = result
   else:
     result = newTransNode(n)
@@ -720,7 +667,7 @@ type
     paDirectMapping, paFastAsgn, paFastAsgnTakeTypeFromArg
     paVarAsgn, paComplexOpenarray, paViaIndirection
 
-proc putArgInto(arg: PNode, formal: PType; borrowedFirstArg = false): TPutArgInto =
+proc putArgInto(arg: PNode, formal: PType): TPutArgInto =
   # This analyses how to treat the mapping "formal <-> arg" in an
   # inline context.
   if formal.kind == tyTypeDesc: return paDirectMapping
@@ -747,11 +694,6 @@ proc putArgInto(arg: PNode, formal: PType; borrowedFirstArg = false): TPutArgInt
   of nkAddr, nkHiddenAddr:
     result = putArgInto(arg[0], formal)
     if result == paViaIndirection: result = paFastAsgn
-  of nkHiddenStdConv, nkHiddenSubConv, nkConv:
-    if compareTypes(arg.typ, arg[1].typ, dcEqIgnoreDistinct, {IgnoreRangeShallow}):
-      result = putArgInto(arg[1], formal)
-    else:
-      result = paFastAsgn
   of nkCurly, nkBracket:
     for i in 0..<arg.len:
       if putArgInto(arg[i], formal) != paDirectMapping:
@@ -771,13 +713,6 @@ proc putArgInto(arg: PNode, formal: PType; borrowedFirstArg = false): TPutArgInt
     if skipTypes(formal, abstractInst).kind in {tyVar, tyLent}: result = paVarAsgn
     else: result = paFastAsgn
 
-  if borrowedFirstArg and result == paDirectMapping and parampatterns.exprRoot(arg) == nil and
-           parampatterns.isAssignable(nil, arg) == arNone:
-    # Inline iterators like `items(array)` borrow from the first argument.
-    # If that argument is just a transient expression, materialize it so the
-    # lifted closure keeps the backing storage alive across yields.
-    result = paFastAsgnTakeTypeFromArg
-
 proc findWrongOwners(c: PTransf, n: PNode) =
   if n.kind == nkVarSection:
     let x = n[0][0]
@@ -850,9 +785,7 @@ proc transformFor(c: PTransf, n: PNode): PNode =
 
   discard c.breakSyms.pop
 
-  var iter = call[0].sym
-  if sfBorrow in iter.flags and iter.kind in routineKinds:
-    iter = resolveBorrowedRoutineSym(c, iter, n.info)
+  let iter = call[0].sym
 
   var v = newNodeI(nkVarSection, n.info)
   for i in 0..<n.len - 2:
@@ -876,16 +809,13 @@ proc transformFor(c: PTransf, n: PNode): PNode =
   if iter.kind != skIterator: return result
   # generate access statements for the parameters (unless they are constant)
   pushTransCon(c, newC)
-  let borrowedIterResult =
-    iter.typ != nil and iter.typ.returnType != nil and
-    skipTypes(iter.typ.returnType, abstractInst).kind in {tyLent, tyVar}
   for i in 1..<call.len:
     var arg = transform(c, call[i])
     let ff = skipTypes(iter.typ, abstractInst)
     # can happen for 'nim check':
     if i >= ff.n.len: return result
     var formal = ff.n[i].sym
-    let pa = putArgInto(arg, formal.typ, borrowedIterResult and i == 1)
+    let pa = putArgInto(arg, formal.typ)
     case pa
     of paDirectMapping:
       newC.mapping[formal.itemId] = arg
@@ -1260,13 +1190,6 @@ proc transform(c: PTransf, n: PNode, noConstFold = false): PNode =
     # no need to transform type sections:
     return n
   of nkVarSection, nkLetSection:
-    # NIF loads let/var sections with bare nkSym children instead of nkIdentDefs.
-    # Expand them so transformSons reaches the value expression (e.g. for-loop).
-    for i in 0 ..< n.len:
-      if n[i].kind == nkSym:
-        let impl = n[i].sym.ast  # triggers lazy load if Partial
-        if impl != nil and impl.kind == nkIdentDefs:
-          n[i] = impl
     if c.inlining > 0:
       # we need to copy the variables for multiple yield statements:
       result = transformVarSection(c, n)

compiler/typeallowed.nim

@@ -99,13 +99,12 @@ proc typeAllowedAux(marker: var IntSet, typ: PType, kind: TSymKind,
       if isInlineIterator(typ) and kind in {skVar, skLet, skConst, skParam, skResult}:
         # only closure iterators may be assigned to anything.
         result = t
-      let innerFlags = flags - {taObjField, taTupField, taIsOpenArray}
-      let f = if kind in {skProc, skFunc}: innerFlags+{taNoUntyped} else: innerFlags
+      let f = if kind in {skProc, skFunc}: flags+{taNoUntyped} else: flags
       for _, a in t.paramTypes:
         if result != nil: break
-        result = typeAllowedAux(marker, a, skParam, c, f)
+        result = typeAllowedAux(marker, a, skParam, c, f-{taIsOpenArray})
       if result.isNil and t.returnType != nil:
-        result = typeAllowedAux(marker, t.returnType, skResult, c, innerFlags)
+        result = typeAllowedAux(marker, t.returnType, skResult, c, flags)
   of tyTypeDesc:
     if kind in {skVar, skLet, skConst} and taProcContextIsNotMacro in flags:
       result = t

compiler/typekeys.nim

@@ -10,7 +10,7 @@
 ## Based on sighashes.nim but works on astdef directly as we need it in ast2nif.nim.
 ## Also produces more readable names thanks to treemangler.
 
-import std/[assertions, sets]
+import std/assertions
 
 import "../dist/nimony/src/lib" / [treemangler]
 import "../dist/nimony/src/gear2" / modnames
@@ -54,9 +54,6 @@ type
     m: Mangler
     tl: TypeLoader
     sl: SymLoader
-    visited: HashSet[ItemId]  # anonymous object types whose fields are currently
-                              # being hashed — a non-mutating guard against endless
-                              # recursion when a field references the type itself.
 
 proc typeKey(c: var Context; t: PType; flags: set[ConsiderFlag]; conf: ConfigRef)
 proc symKey(c: var Context; s: PSym; conf: ConfigRef) =
@@ -70,26 +67,14 @@ proc symKey(c: var Context; s: PSym; conf: ConfigRef) =
     name.add '.'
     name.addInt s.disamb
 
-    # The owner may still be an unloaded stub (kind `skStub`): force it in
-    # before inspecting its kind, otherwise the module suffix is silently
-    # dropped from the key and def-vs-use keys diverge — e.g. `Lexer`'s base
-    # class keyed as `TBaseLexer.0.` at nifc vs `TBaseLexer.0.nimqydn3y` at
-    # sem time, making `getAttachedOp` miss ("'=destroy' operator not found").
-    template forceLoaded(x: PSym): PSym =
-      let tmp = x
-      if tmp != nil and tmp.state == Partial and c.sl != nil: c.sl(tmp)
-      tmp
-
-    let owner = forceLoaded(s.ownerFieldImpl)
     let it =
       if s.kindImpl == skModule:
         s
-      elif s.kindImpl in skProcKinds and sfFromGeneric in s.flagsImpl and
-           owner != nil and owner.kindImpl != skModule:
-        forceLoaded(owner.ownerFieldImpl)
+      elif s.kindImpl in skProcKinds and sfFromGeneric in s.flagsImpl and s.ownerFieldImpl.kindImpl != skModule:
+        s.ownerFieldImpl.ownerFieldImpl
       else:
-        owner
-    if it != nil and it.kindImpl == skModule:
+        s.ownerFieldImpl
+    if it.kindImpl == skModule:
       name.add '.'
       name.add modname(it, conf)
     c.m.addSymbol(name)
@@ -153,12 +138,7 @@ proc typeKey(c: var Context; t: PType; flags: set[ConsiderFlag]; conf: ConfigRef
     for a in t.sonsImpl:
       c.typeKey a, flags, conf
   of tyDistinct:
-    if t.sonsImpl.len == 0:
-      # a bare `distinct` typeclass (e.g. `foo(distinct, ...)` matched
-      # against a `T: type` param) has no base type to key — it IS its kind
-      withTree c.m, toNifTag(t.kind):
-        c.m.addEmpty()
-    elif CoDistinct in flags:
+    if CoDistinct in flags:
       if t.symImpl != nil: symKey(c, t.symImpl, conf)
       if t.symImpl == nil or tfFromGeneric in t.flagsImpl:
         c.typeKey t.sonsImpl[^1], flags, conf
@@ -167,14 +147,7 @@ proc typeKey(c: var Context; t: PType; flags: set[ConsiderFlag]; conf: ConfigRef
     else:
       symKey(c, t.symImpl, conf)
   of tyGenericInst:
-    # The generic head (son[0]) may be a lazily-loaded stub under IC; ensure it
-    # is materialised before peeking at its symbol. A nil sym means this is not
-    # an imported C++ generic, so fall through to the normal `skipModifierB`.
-    var base = t.sonsImpl[0]
-    if base.state == Partial:
-      assert c.tl != nil
-      c.tl(base)
-    if base.symImpl != nil and sfInfixCall in base.symImpl.flagsImpl:
+    if sfInfixCall in t.sonsImpl[0].symImpl.flagsImpl:
       # This is an imported C++ generic type.
       # We cannot trust the `lastSon` to hold a properly populated and unique
       # value for each instantiation, so we hash the generic parameters here:
@@ -243,48 +216,14 @@ proc typeKey(c: var Context; t: PType; flags: set[ConsiderFlag]; conf: ConfigRef
     if t.typeInstImpl != nil:
       # prevent against infinite recursions here, see bug #8883:
       let inst = t.typeInstImpl
-      if inst.state == Partial:
-        # a lazily-loaded typeInst stub has no sons until forced in
-        assert c.tl != nil
-        c.tl(inst)
       t.typeInstImpl = nil # IC: spurious writes are ok since we set it back immediately
       assert inst.kind == tyGenericInst
-      if inst.sonsImpl.len > 0:
-        c.typeKey inst.sonsImpl[0], flags, conf
+      c.typeKey inst.sonsImpl[0], flags, conf
       for i in 1..<inst.sonsImpl.len-1:
-        # Match sighashes: generic-instantiation arguments are keyed with
-        # `CoDistinct` so distinct args are not collapsed to their base.
-        c.typeKey inst.sonsImpl[i], flags+{CoDistinct}, conf
+        c.typeKey inst.sonsImpl[i], flags, conf
       t.typeInstImpl = inst
     elif t.symImpl != nil:
       c.symKey(t.symImpl, conf)
-      # Anonymous / gensym'd object types (e.g. closure environments and
-      # `ref object` ObjectTypes) share the placeholder name `´anon`, so `symKey`
-      # alone collapses every one of them onto the same key — which made distinct
-      # closure-env `=destroy`/`=sink` hooks collide. Mirror sighashes: when the
-      # type symbol is anonymous/gensym'd, disambiguate further by keying the
-      # field types and names (or `.empty` when there are none).
-      template hasFlag(sym: PSym): bool =
-        {sfAnon, sfGenSym} * sym.flagsImpl != {}
-      if hasFlag(t.symImpl) or
-         (t.kind == tyObject and t.ownerFieldImpl != nil and t.ownerFieldImpl.kindImpl == skType and
-          t.ownerFieldImpl.typImpl != nil and t.ownerFieldImpl.typImpl.kind == tyRef and hasFlag(t.ownerFieldImpl)):
-        if t.nImpl != nil and t.nImpl.len > 0:
-          # Guard against endless recursion when a field references this type
-          # itself. Unlike sighashes (which temporarily clears `sfAnon`/`sfGenSym`
-          # on the symbol), do NOT mutate: `typeKey` runs during sem — it is
-          # called unconditionally from `modulegraphs.setAttachedOp` — so a
-          # mutation that an assertion deeper in `treeKey` left unrestored would
-          # corrupt the type. `symKey` above already emitted the type's identity,
-          # so on a back-reference we simply stop.
-          if not containsOrIncl(c.visited, t.itemId):
-            c.treeKey(t.nImpl, flags + {CoHashTypeInsideNode}, conf)
-            c.visited.excl t.itemId
-        else:
-          c.m.addIdent "´empty"
-      # Object inheritance is part of identity: key the base class too.
-      if t.kind == tyObject and t.sonsImpl.len > 0 and t.sonsImpl[0] != nil:
-        c.typeKey t.sonsImpl[0], flags, conf
     else:
       c.m.addIdent "`bug"
   of tyFromExpr:
@@ -299,19 +238,10 @@ proc typeKey(c: var Context; t: PType; flags: set[ConsiderFlag]; conf: ConfigRef
             c.symKey(t.nImpl[i].sym, conf)
             c.typeKey(t.nImpl[i].sym.typImpl, flags+{CoIgnoreRange}, conf)
       else:
-        # ALL sons are tuple fields (son 0 included — unlike tyProc, where
-        # son 0 is the return type). Starting at 1 dropped the first field,
-        # collapsing e.g. `(PSym, NifIndexEntry)` and `(PType, NifIndexEntry)`
-        # onto one key, so hook lookup called the wrong `=destroy`/`=sink`
-        # (incompatible-argument C errors). Mirrors sighashes' `for a in t.kids`.
-        for i in 0..<t.sonsImpl.len:
+        for i in 1..<t.sonsImpl.len:
           c.typeKey t.sonsImpl[i], flags+{CoIgnoreRange}, conf
   of tyRange:
-    if t.sonsImpl.len == 0:
-      # bare `range` typeclass: no base type, key the kind alone
-      withTree c.m, toNifTag(t.kind):
-        c.m.addEmpty()
-    elif CoIgnoreRange notin flags:
+    if CoIgnoreRange notin flags:
       withTree c.m, toNifTag(t.kind):
         c.treeKey(t.nImpl, {}, conf)
         c.typeKey(t.sonsImpl[^1], flags, conf)
@@ -324,28 +254,12 @@ proc typeKey(c: var Context; t: PType; flags: set[ConsiderFlag]; conf: ConfigRef
         c.typeKey(t.skipModifierB, flags, conf)
   of tyProc:
     withTree c.m, (if tfIterator in t.flagsImpl: "itertype" else: "proctype"):
-      # Proc parameter *types* are part of the type's identity. Under IC the
-      # parameters live in `nImpl` (`sonsImpl` holds only the return type), so a
-      # loaded proc type has an empty `sonsImpl[1..]`; reading params from there
-      # would silently drop them and collide every same-return/same-callconv
-      # closure onto one key (e.g. `proc(cb: proc())` onto bare `proc()`),
-      # which made hook lookup resolve to the wrong `=copy`. Prefer `nImpl`
-      # (consistent in-memory and after load); hash param types only, not their
-      # symbols — parameter names do not affect type identity.
-      if t.nImpl != nil and t.nImpl.kind == nkFormalParams:
+      if CoProc in flags and t.nImpl != nil:
         let params = t.nImpl
         for i in 1..<params.len:
-          if params[i].kind == nkSym:
-            # The param sym may be a lazily-loaded stub: force it in (as `symKey`
-            # does) so its type is available, then hash the param *type* only —
-            # parameter names are not part of the type's identity. Without the
-            # load the type reads back nil at codegen and the key silently loses
-            # its parameters (collapsing distinct closure types onto one key).
-            let ps = params[i].sym
-            if ps.state == Partial and c.sl != nil: c.sl(ps)
-            c.typeKey(ps.typImpl, flags, conf)
-          else:
-            c.typeKey(params[i].typField, flags, conf)
+          let param = params[i].sym
+          c.symKey(param, conf)
+          c.typeKey(param.typImpl, flags, conf)
       else:
         for i in 1..<t.sonsImpl.len:
           c.typeKey(t.sonsImpl[i], flags, conf)
@@ -356,30 +270,16 @@ proc typeKey(c: var Context; t: PType; flags: set[ConsiderFlag]; conf: ConfigRef
       if tfVarargs in t.flagsImpl: c.m.addIdent "´varargs"
   of tyArray:
     withTree c.m, toNifTag(t.kind):
-      if t.sonsImpl.len == 0:
-        # bare `array` typeclass: no element/index types
-        c.m.addEmpty()
-      else:
-        c.typeKey(t.sonsImpl[^1], flags-{CoIgnoreRange}, conf)
-        c.typeKey(t.sonsImpl[0], flags-{CoIgnoreRange}, conf)
+      c.typeKey(t.sonsImpl[^1], flags-{CoIgnoreRange}, conf)
+      c.typeKey(t.sonsImpl[0], flags-{CoIgnoreRange}, conf)
   else:
     withTree c.m, toNifTag(t.kind):
-      for i in 0..<t.sonsImpl.len:
+      for i in 1..<t.sonsImpl.len:
         c.typeKey t.sonsImpl[i], flags, conf
       if tfNotNil in t.flagsImpl and CoType notin flags:
         c.m.addIdent "´notnil"
 
 proc typeKey*(t: PType; conf: ConfigRef; tl: TypeLoader; sl: SymLoader): string =
-  var c: Context = Context(m: createMangler(30, -1), tl: tl, sl: sl,
-                           visited: initHashSet[ItemId]())
-  # Mirror the flags liftdestructors uses for its `canonTypes` hash
-  # (`hashType(skipped, {CoType, CoConsiderOwned, CoDistinct})`): hook keys must
-  # distinguish what hook *lifting* distinguishes. With empty flags a generic
-  # `distinct` instance (e.g. nilcheck's `SeqOfDistinct[T, U]`) took the bare
-  # `symKey` branch — the sym is the generic's and thus SHARED by all
-  # instances, so `SeqOfDistinct[I, PNode]` and `SeqOfDistinct[I, Nilability]`
-  # collided onto one key and hook lookup returned the wrong `=sink`
-  # ("incompatible type for argument" in the generated C). Under `CoDistinct` a
-  # `tfFromGeneric` distinct keys as sym + base type, keeping instances apart.
-  typeKey(c, t, {CoType, CoConsiderOwned, CoDistinct}, conf)
+  var c: Context = Context(m: createMangler(30, -1), tl: tl, sl: sl)
+  typeKey(c, t, {}, conf)
   result = c.m.extract()

compiler/types.nim

@@ -18,9 +18,21 @@ import std/[intsets, strutils]
 when defined(nimPreviewSlimSystem):
   import std/[assertions, formatfloat]
 
-export isResolvedUserTypeClass, TPreferedDesc, typeToString
-
 type
+  TPreferedDesc* = enum
+    preferName, # default
+    preferDesc, # probably should become what preferResolved is
+    preferExported,
+    preferModuleInfo, # fully qualified
+    preferGenericArg,
+    preferTypeName,
+    preferResolved, # fully resolved symbols
+    preferMixed,
+      # most useful, shows: symbol + resolved symbols if it differs, e.g.:
+      # tuple[a: MyInt{int}, b: float]
+    preferInlayHint,
+    preferInferredEffects,
+
   TTypeRelation* = enum      # order is important!
     isNone, isConvertible,
     isIntConv,
@@ -43,6 +55,8 @@ type
     pcmNotIterator
     pcmDifferentCallConv
 
+proc typeToString*(typ: PType; prefer: TPreferedDesc = preferName): string
+
 proc addTypeDeclVerboseMaybe*(result: var string, conf: ConfigRef; typ: PType) =
   if optDeclaredLocs in conf.globalOptions:
     result.add typeToString(typ, preferMixed)
@@ -50,6 +64,8 @@ proc addTypeDeclVerboseMaybe*(result: var string, conf: ConfigRef; typ: PType) =
   else:
     result.add typeToString(typ)
 
+template `$`*(typ: PType): string = typeToString(typ)
+
 # ------------------- type iterator: ----------------------------------------
 type
   TTypeIter* = proc (t: PType, closure: RootRef): bool {.nimcall.} # true if iteration should stop
@@ -141,9 +157,15 @@ proc getFloatValue*(n: PNode): BiggestFloat =
   of nkHiddenStdConv: getFloatValue(n[1])
   else: NaN
 
+proc isIntLit*(t: PType): bool {.inline.} =
+  result = t.kind == tyInt and t.n != nil and t.n.kind == nkIntLit
+
+proc isFloatLit*(t: PType): bool {.inline.} =
+  result = t.kind == tyFloat and t.n != nil and t.n.kind == nkFloatLit
+
 proc addTypeHeader*(result: var string, conf: ConfigRef; typ: PType; prefer: TPreferedDesc = preferMixed; getDeclarationPath = true) =
   result.add typeToString(typ, prefer)
-  if getDeclarationPath and typ.sym != nil: result.addDeclaredLoc(conf, typ.sym)
+  if getDeclarationPath: result.addDeclaredLoc(conf, typ.sym)
 
 proc getProcHeader*(conf: ConfigRef; sym: PSym; prefer: TPreferedDesc = preferName; getDeclarationPath = true): string =
   assert sym != nil
@@ -438,10 +460,337 @@ proc canFormAcycle*(g: ModuleGraph, typ: PType): bool =
   let t = skipTypes(typ, abstractInst+{tyOwned}-{tyTypeDesc})
   result = canFormAcycleAux(g, marker, t, t, false, false)
 
+proc valueToString(a: PNode): string =
+  case a.kind
+  of nkCharLit, nkUIntLit..nkUInt64Lit:
+    result = $cast[uint64](a.intVal)
+  of nkIntLit..nkInt64Lit:
+    result = $a.intVal
+  of nkFloatLit..nkFloat128Lit: result = $a.floatVal
+  of nkStrLit..nkTripleStrLit: result = a.strVal
+  of nkStaticExpr: result = "static(" & a[0].renderTree & ")"
+  else: result = "<invalid value>"
+
+proc rangeToStr(n: PNode): string =
+  assert(n.kind == nkRange)
+  result = valueToString(n[0]) & ".." & valueToString(n[1])
+
+const
+  typeToStr: array[TTypeKind, string] = ["None", "bool", "char", "empty",
+    "Alias", "typeof(nil)", "untyped", "typed", "typeDesc",
+    # xxx typeDesc=>typedesc: typedesc is declared as such, and is 10x more common.
+    "GenericInvocation", "GenericBody", "GenericInst", "GenericParam",
+    "distinct $1", "enum", "ordinal[$1]", "array[$1, $2]", "object", "tuple",
+    "set[$1]", "range[$1]", "ptr ", "ref ", "var ", "seq[$1]", "proc",
+    "pointer", "OpenArray[$1]", "string", "cstring", "Forward",
+    "int", "int8", "int16", "int32", "int64",
+    "float", "float32", "float64", "float128",
+    "uint", "uint8", "uint16", "uint32", "uint64",
+    "owned", "sink",
+    "lent ", "varargs[$1]", "UncheckedArray[$1]", "Error Type",
+    "BuiltInTypeClass", "UserTypeClass",
+    "UserTypeClassInst", "CompositeTypeClass", "inferred",
+    "and", "or", "not", "any", "static", "TypeFromExpr", "concept", # xxx bugfix
+    "void", "iterable"]
+
+const preferToResolveSymbols = {preferName, preferTypeName, preferModuleInfo,
+  preferGenericArg, preferResolved, preferMixed, preferInlayHint, preferInferredEffects}
+
 template bindConcreteTypeToUserTypeClass*(tc, concrete: PType) =
   tc.add concrete
   tc.incl tfResolved
 
+# TODO: It would be a good idea to kill the special state of a resolved
+# concept by switching to tyAlias within the instantiated procs.
+# Currently, tyAlias is always skipped with skipModifier, which means that
+# we can store information about the matched concept in another position.
+# Then builtInFieldAccess can be modified to properly read the derived
+# consts and types stored within the concept.
+template isResolvedUserTypeClass*(t: PType): bool =
+  tfResolved in t.flags
+
+proc addTypeFlags(name: var string, typ: PType) {.inline.} =
+  if tfNotNil in typ.flags: name.add(" not nil")
+
+proc typeToString(typ: PType, prefer: TPreferedDesc = preferName): string =
+  let preferToplevel = prefer
+  proc getPrefer(prefer: TPreferedDesc): TPreferedDesc =
+    if preferToplevel in {preferResolved, preferMixed}:
+      preferToplevel # sticky option
+    else:
+      prefer
+
+  proc typeToString(typ: PType, prefer: TPreferedDesc = preferName): string =
+    result = ""
+    let prefer = getPrefer(prefer)
+    let t = typ
+    if t == nil: return
+    if prefer in preferToResolveSymbols and t.sym != nil and
+         sfAnon notin t.sym.flags and t.kind notin {tySequence, tyInferred}:
+      if t.kind == tyInt and isIntLit(t):
+        if prefer == preferInlayHint:
+          result = t.sym.name.s
+        else:
+          result = t.sym.name.s & " literal(" & $t.n.intVal & ")"
+      elif t.kind == tyAlias and t.elementType.kind != tyAlias:
+        result = typeToString(t.elementType)
+      elif prefer in {preferResolved, preferMixed}:
+        case t.kind
+        of IntegralTypes + {tyFloat..tyFloat128} + {tyString, tyCstring}:
+          result = typeToStr[t.kind]
+        of tyGenericBody:
+          result = typeToString(t.last)
+        of tyCompositeTypeClass:
+          # avoids showing `A[any]` in `proc fun(a: A)` with `A = object[T]`
+          result = typeToString(t.last.last)
+        else:
+          result = t.sym.name.s
+        if prefer == preferMixed and result != t.sym.name.s:
+          result = t.sym.name.s & "{" & result & "}"
+      elif prefer in {preferName, preferTypeName, preferInlayHint, preferInferredEffects} or t.sym.owner.isNil:
+        # note: should probably be: {preferName, preferTypeName, preferGenericArg}
+        result = t.sym.name.s
+        if t.kind == tyGenericParam and t.genericParamHasConstraints:
+          result.add ": "
+          result.add t.elementType.typeToString
+      else:
+        result = t.sym.owner.name.s & '.' & t.sym.name.s
+      result.addTypeFlags(t)
+      return
+    case t.kind
+    of tyInt:
+      if not isIntLit(t) or prefer == preferExported:
+        result = typeToStr[t.kind]
+      else:
+        case prefer:
+        of preferGenericArg:
+          result = $t.n.intVal
+        of preferInlayHint:
+          result = "int"
+        else:
+          result = "int literal(" & $t.n.intVal & ")"
+    of tyGenericInst:
+      result = typeToString(t.genericHead) & '['
+      for needsComma, a in t.genericInstParams:
+        if needsComma: result.add(", ")
+        result.add(typeToString(a, preferGenericArg))
+      result.add(']')
+    of tyGenericInvocation:
+      result = typeToString(t.genericHead) & '['
+      for needsComma, a in t.genericInvocationParams:
+        if needsComma: result.add(", ")
+        result.add(typeToString(a, preferGenericArg))
+      result.add(']')
+    of tyGenericBody:
+      result = typeToString(t.typeBodyImpl) & '['
+      for i, a in t.genericBodyParams:
+        if i > 0: result.add(", ")
+        result.add(typeToString(a, preferTypeName))
+      result.add(']')
+    of tyTypeDesc:
+      if t.elementType.kind == tyNone: result = "typedesc"
+      else: result = "typedesc[" & typeToString(t.elementType) & "]"
+    of tyStatic:
+      if prefer == preferGenericArg and t.n != nil:
+        result = t.n.renderTree
+      else:
+        result = "static[" & (if t.hasElementType: typeToString(t.skipModifier) else: "") & "]"
+        if t.n != nil: result.add "(" & renderTree(t.n) & ")"
+    of tyUserTypeClass:
+      if t.sym != nil and t.sym.owner != nil:
+        if t.isResolvedUserTypeClass: return typeToString(t.last)
+        return t.sym.owner.name.s
+      else:
+        result = "<invalid tyUserTypeClass>"
+    of tyBuiltInTypeClass:
+      result =
+        case t.base.kind
+        of tyVar: "var"
+        of tyRef: "ref"
+        of tyPtr: "ptr"
+        of tySequence: "seq"
+        of tyArray: "array"
+        of tySet: "set"
+        of tyRange: "range"
+        of tyDistinct: "distinct"
+        of tyProc: "proc"
+        of tyObject: "object"
+        of tyTuple: "tuple"
+        of tyOpenArray: "openArray"
+        else: typeToStr[t.base.kind]
+    of tyInferred:
+      let concrete = t.previouslyInferred
+      if concrete != nil: result = typeToString(concrete)
+      else: result = "inferred[" & typeToString(t.base) & "]"
+    of tyUserTypeClassInst:
+      let body = t.base
+      result = body.sym.name.s & "["
+      for needsComma, a in t.userTypeClassInstParams:
+        if needsComma: result.add(", ")
+        result.add(typeToString(a))
+      result.add "]"
+    of tyAnd:
+      for i, son in t.ikids:
+        if i > 0: result.add(" and ")
+        result.add(typeToString(son))
+    of tyOr:
+      for i, son in t.ikids:
+        if i > 0: result.add(" or ")
+        result.add(typeToString(son))
+    of tyNot:
+      result = "not " & typeToString(t.elementType)
+    of tyUntyped:
+      #internalAssert t.len == 0
+      result = "untyped"
+    of tyFromExpr:
+      if t.n == nil:
+        result = "unknown"
+      else:
+        result = "typeof(" & renderTree(t.n) & ")"
+    of tyArray:
+      result = "array"
+      if t.hasElementType:
+        if t.indexType.kind == tyRange:
+          result &= "[" & rangeToStr(t.indexType.n) & ", " &
+              typeToString(t.elementType) & ']'
+        else:
+          result &= "[" & typeToString(t.indexType) & ", " &
+              typeToString(t.elementType) & ']'
+    of tyUncheckedArray:
+      result = "UncheckedArray"
+      if t.hasElementType:
+        result &= "[" & typeToString(t.elementType) & ']'
+    of tySequence:
+      if t.sym != nil and prefer != preferResolved:
+        result = t.sym.name.s
+      else:
+        result = "seq"
+        if t.hasElementType:
+          result &= "[" & typeToString(t.elementType) & ']'
+    of tyOrdinal:
+      result = "ordinal"
+      if t.hasElementType:
+        result &= "[" & typeToString(t.skipModifier) & ']'
+    of tySet:
+      result = "set"
+      if t.hasElementType:
+        result &= "[" & typeToString(t.elementType) & ']'
+    of tyOpenArray:
+      result = "openArray"
+      if t.hasElementType:
+        result &= "[" & typeToString(t.elementType) & ']'
+    of tyDistinct:
+      result = "distinct " & typeToString(t.elementType,
+        if prefer == preferModuleInfo: preferModuleInfo else: preferTypeName)
+    of tyIterable:
+      # xxx factor this pattern
+      result = "iterable"
+      if t.hasElementType:
+        result &= "[" & typeToString(t.skipModifier) & ']'
+    of tyTuple:
+      # we iterate over t.sons here, because t.n may be nil
+      if t.n != nil:
+        result = "tuple["
+        for i in 0..<t.n.len:
+          assert(t.n[i].kind == nkSym)
+          result.add(t.n[i].sym.name.s & ": " & typeToString(t.n[i].sym.typ))
+          if i < t.n.len - 1: result.add(", ")
+        result.add(']')
+      elif t.isEmptyTupleType:
+        result = "tuple[]"
+      elif t.isSingletonTupleType:
+        result = "("
+        for son in t.kids:
+          result.add(typeToString(son))
+        result.add(",)")
+      else:
+        result = "("
+        for i, son in t.ikids:
+          if i > 0: result.add ", "
+          result.add(typeToString(son))
+        result.add(')')
+    of tyPtr, tyRef, tyVar, tyLent:
+      result = if isOutParam(t): "out " else: typeToStr[t.kind]
+      result.add typeToString(t.elementType)
+    of tyRange:
+      result = "range "
+      if t.n != nil and t.n.kind == nkRange:
+        result.add rangeToStr(t.n)
+      if prefer != preferExported:
+        result.add("(" & typeToString(t.elementType) & ")")
+    of tyProc:
+      result = if tfIterator in t.flags: "iterator "
+               elif t.owner != nil:
+                 case t.owner.kind
+                 of skTemplate: "template "
+                 of skMacro: "macro "
+                 of skConverter: "converter "
+                 else: "proc "
+              else:
+                "proc "
+      if tfUnresolved in t.flags: result.add "[*missing parameters*]"
+      result.add "("
+      for i, a in t.paramTypes:
+        if i > FirstParamAt: result.add(", ")
+        let j = paramTypeToNodeIndex(i)
+        if t.n != nil and j < t.n.len and t.n[j].kind == nkSym:
+          result.add(t.n[j].sym.name.s)
+          result.add(": ")
+        result.add(typeToString(a))
+      result.add(')')
+      if t.returnType != nil: result.add(": " & typeToString(t.returnType))
+      var prag = if t.callConv == ccNimCall and tfExplicitCallConv notin t.flags: "" else: $t.callConv
+      var hasImplicitRaises = false
+      if not isNil(t.owner) and not isNil(t.owner.ast) and (t.owner.ast.len - 1) >= pragmasPos:
+        let pragmasNode = t.owner.ast[pragmasPos]
+        let raisesSpec = effectSpec(pragmasNode, wRaises)
+        if not isNil(raisesSpec):
+          addSep(prag)
+          prag.add("raises: ")
+          prag.add($raisesSpec)
+          hasImplicitRaises = true
+      if tfNoSideEffect in t.flags:
+        addSep(prag)
+        prag.add("noSideEffect")
+      if tfThread in t.flags:
+        addSep(prag)
+        prag.add("gcsafe")
+      var effectsOfStr = ""
+      for i, a in t.paramTypes:
+        let j = paramTypeToNodeIndex(i)
+        if t.n != nil and j < t.n.len and t.n[j].kind == nkSym and t.n[j].sym.kind == skParam and sfEffectsDelayed in t.n[j].sym.flags:
+          addSep(effectsOfStr)
+          effectsOfStr.add(t.n[j].sym.name.s)
+      if effectsOfStr != "":
+        addSep(prag)
+        prag.add("effectsOf: ")
+        prag.add(effectsOfStr)
+      if not hasImplicitRaises and prefer == preferInferredEffects and not isNil(t.owner) and not isNil(t.owner.typ) and not isNil(t.owner.typ.n) and (t.owner.typ.n.len > 0):
+        let effects = t.n[0]
+        if effects.kind == nkEffectList and effects.len == effectListLen:
+          var inferredRaisesStr = ""
+          let effs = effects[exceptionEffects]
+          if not isNil(effs):
+            for eff in items(effs):
+              if not isNil(eff):
+                addSep(inferredRaisesStr)
+                inferredRaisesStr.add($eff.typ)
+          addSep(prag)
+          prag.add("raises: <inferred> [")
+          prag.add(inferredRaisesStr)
+          prag.add("]")
+      if prag.len != 0: result.add("{." & prag & ".}")
+    of tyVarargs:
+      result = typeToStr[t.kind] % typeToString(t.elementType)
+    of tySink:
+      result = "sink " & typeToString(t.skipModifier)
+    of tyOwned:
+      result = "owned " & typeToString(t.elementType)
+    else:
+      result = typeToStr[t.kind]
+    result.addTypeFlags(t)
+  result = typeToString(typ, prefer)
+
 proc firstOrd*(conf: ConfigRef; t: PType): Int128 =
   case t.kind
   of tyBool, tyChar, tySequence, tyOpenArray, tyString, tyVarargs, tyError:
@@ -897,7 +1246,7 @@ proc sameTypeAux(x, y: PType, c: var TSameTypeClosure): bool =
     c.flags = oldFlags
 
   if x == y: return true
-  let aliasSkipSet = maybeSkipRange({tyAlias, tyInferred})
+  let aliasSkipSet = maybeSkipRange({tyAlias})
   var a = skipTypes(x, aliasSkipSet)
   while a.kind == tyUserTypeClass and tfResolved in a.flags:
     a = skipTypes(a.last, aliasSkipSet)
@@ -1069,10 +1418,9 @@ proc sameBackendTypeIgnoreRange*(x, y: PType): bool =
   c.cmp = dcEqIgnoreDistinct
   result = sameTypeAux(x, y, c)
 
-proc sameBackendTypePickyAliases*(x, y: PType, flags: TTypeCmpFlags = {}): bool =
+proc sameBackendTypePickyAliases*(x, y: PType): bool =
   var c = initSameTypeClosure()
   c.flags.incl {IgnoreTupleFields, IgnoreRangeShallow, PickyCAliases, PickyBackendAliases}
-  c.flags.incl flags
   c.cmp = dcEqIgnoreDistinct
   result = sameTypeAux(x, y, c)
 
@@ -1780,7 +2128,3 @@ proc reduceToBase*(f: PType): PType =
     result = f.elementType
   else:
     result = f
-
-proc supportsCopyMem*(t: PType): bool =
-  let t = t.skipTypes({tyVar, tyLent, tyGenericInst, tyAlias, tySink, tyInferred})
-  result = not containsGarbageCollectedRef(t) and not hasDestructor(t)