diff --git a/build_all.bat b/build_all.bat
index ef4a5f6a4e..bef7956f28 100644
--- a/build_all.bat
+++ b/build_all.bat
@@ -24,6 +24,6 @@ if not exist %nim_csources% (
   cd ..
   copy /y bin\nim.exe  %nim_csources%
 )
- bin\nim.exe c --noNimblePath --skipUserCfg --skipParentCfg --hints:off koch
- koch boot -d:release --skipUserCfg --skipParentCfg --hints:off
- koch tools --skipUserCfg --skipParentCfg --hints:off
+bin\nim.exe c --noNimblePath --skipUserCfg --skipParentCfg --hints:off koch
+koch boot -d:release --skipUserCfg --skipParentCfg --hints:off
+koch tools --skipUserCfg --skipParentCfg --hints:off
diff --git a/changelog.md b/changelog.md
index e17b24b428..1310b6ae3f 100644
--- a/changelog.md
+++ b/changelog.md
@@ -14,6 +14,11 @@ rounding guarantees (via the
 
 ## Standard library additions and changes
 
+[//]: # "Additions:"
+- `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.
+
 [//]: # "Changes:"
 - `std/math` The `^` symbol now supports floating-point as exponent in addition to the Natural type.
 
diff --git a/compiler/ast.nim b/compiler/ast.nim
index e2f335655b..6902d3a599 100644
--- a/compiler/ast.nim
+++ b/compiler/ast.nim
@@ -491,7 +491,7 @@ type
     mAnd, mOr,
     mImplies, mIff, mExists, mForall, mOld,
     mEqStr, mLeStr, mLtStr,
-    mEqSet, mLeSet, mLtSet, mMulSet, mPlusSet, mMinusSet,
+    mEqSet, mLeSet, mLtSet, mMulSet, mPlusSet, mMinusSet, mXorSet,
     mConStrStr, mSlice,
     mDotDot, # this one is only necessary to give nice compile time warnings
     mFields, mFieldPairs, mOmpParFor,
@@ -559,7 +559,7 @@ const
     mStrToStr, mEnumToStr,
     mAnd, mOr,
     mEqStr, mLeStr, mLtStr,
-    mEqSet, mLeSet, mLtSet, mMulSet, mPlusSet, mMinusSet,
+    mEqSet, mLeSet, mLtSet, mMulSet, mPlusSet, mMinusSet, mXorSet,
     mConStrStr, mAppendStrCh, mAppendStrStr, mAppendSeqElem,
     mInSet, mRepr, mOpenArrayToSeq}
 
@@ -591,7 +591,7 @@ type
   TNode*{.final, acyclic.} = object # on a 32bit machine, this takes 32 bytes
     when defined(useNodeIds):
       id*: int
-    typ*: PType
+    typField: PType
     info*: TLineInfo
     flags*: TNodeFlags
     case kind*: TNodeKind
@@ -708,7 +708,7 @@ type
     when defined(nimsuggest):
       endInfo*: TLineInfo
       hasUserSpecifiedType*: bool  # used for determining whether to display inlay type hints
-    owner*: PSym
+    ownerField: PSym
     flags*: TSymFlags
     ast*: PNode               # syntax tree of proc, iterator, etc.:
                               # the whole proc including header; this is used
@@ -779,7 +779,7 @@ type
                               # formal param list
                               # for concepts, the concept body
                               # else: unused
-    owner*: PSym              # the 'owner' of the type
+    ownerField: PSym          # the 'owner' of the type
     sym*: PSym                # types have the sym associated with them
                               # it is used for converting types to strings
     size*: BiggestInt         # the size of the type in bytes
@@ -818,6 +818,15 @@ type
 
 template nodeId(n: PNode): int = cast[int](n)
 
+template typ*(n: PNode): PType =
+  n.typField
+
+proc owner*(s: PSym|PType): PSym {.inline.} =
+  result = s.ownerField
+
+proc setOwner*(s: PSym|PType, owner: PSym) {.inline.} =
+  s.ownerField = owner
+
 type Gconfig = object
   # we put comments in a side channel to avoid increasing `sizeof(TNode)`, which
   # reduces memory usage given that `PNode` is the most allocated type by far.
@@ -1136,7 +1145,7 @@ proc newNodeIT*(kind: TNodeKind, info: TLineInfo, typ: PType): PNode =
   ## new node with line info, type, and no children
   result = newNode(kind)
   result.info = info
-  result.typ = typ
+  result.typ() = typ
 
 proc newNode*(kind: TNodeKind, info: TLineInfo): PNode =
   ## new node with line info, no type, and no children
@@ -1201,7 +1210,7 @@ proc newSym*(symKind: TSymKind, name: PIdent, idgen: IdGenerator; owner: PSym,
   assert not name.isNil
   let id = nextSymId idgen
   result = PSym(name: name, kind: symKind, flags: {}, info: info, itemId: id,
-                options: options, owner: owner, offset: defaultOffset,
+                options: options, ownerField: owner, offset: defaultOffset,
                 disamb: getOrDefault(idgen.disambTable, name).int32)
   idgen.disambTable.inc name
   when false:
@@ -1282,13 +1291,13 @@ proc newIdentNode*(ident: PIdent, info: TLineInfo): PNode =
 proc newSymNode*(sym: PSym): PNode =
   result = newNode(nkSym)
   result.sym = sym
-  result.typ = sym.typ
+  result.typ() = sym.typ
   result.info = sym.info
 
 proc newSymNode*(sym: PSym, info: TLineInfo): PNode =
   result = newNode(nkSym)
   result.sym = sym
-  result.typ = sym.typ
+  result.typ() = sym.typ
   result.info = info
 
 proc newOpenSym*(n: PNode): PNode {.inline.} =
@@ -1368,7 +1377,7 @@ proc newIntTypeNode*(intVal: BiggestInt, typ: PType): PNode =
     result = newNode(nkIntLit)
   else: raiseAssert $kind
   result.intVal = intVal
-  result.typ = typ
+  result.typ() = typ
 
 proc newIntTypeNode*(intVal: Int128, typ: PType): PNode =
   # XXX: introduce range check
@@ -1507,7 +1516,7 @@ iterator signature*(t: PType): PType =
 
 proc newType*(kind: TTypeKind; idgen: IdGenerator; owner: PSym; son: sink PType = nil): PType =
   let id = nextTypeId idgen
-  result = PType(kind: kind, owner: owner, size: defaultSize,
+  result = PType(kind: kind, ownerField: owner, size: defaultSize,
                  align: defaultAlignment, itemId: id,
                  uniqueId: id, sons: @[])
   if son != nil: result.sons.add son
@@ -1562,7 +1571,7 @@ proc copyType*(t: PType, idgen: IdGenerator, owner: PSym): PType =
   result.sym = t.sym          # backend-info should not be copied
 
 proc exactReplica*(t: PType): PType =
-  result = PType(kind: t.kind, owner: t.owner, size: defaultSize,
+  result = PType(kind: t.kind, ownerField: t.owner, size: defaultSize,
                  align: defaultAlignment, itemId: t.itemId,
                  uniqueId: t.uniqueId)
   assignType(result, t)
@@ -1670,7 +1679,7 @@ proc copyNode*(src: PNode): PNode =
     return nil
   result = newNode(src.kind)
   result.info = src.info
-  result.typ = src.typ
+  result.typ() = src.typ
   result.flags = src.flags * PersistentNodeFlags
   result.comment = src.comment
   when defined(useNodeIds):
@@ -1688,7 +1697,7 @@ proc copyNode*(src: PNode): PNode =
 
 template transitionNodeKindCommon(k: TNodeKind) =
   let obj {.inject.} = n[]
-  n[] = TNode(kind: k, typ: obj.typ, info: obj.info, flags: obj.flags)
+  n[] = TNode(kind: k, typField: n.typ, info: obj.info, flags: obj.flags)
   # n.comment = obj.comment # shouldn't be needed, the address doesnt' change
   when defined(useNodeIds):
     n.id = obj.id
@@ -1711,7 +1720,7 @@ proc transitionNoneToSym*(n: PNode) =
 template transitionSymKindCommon*(k: TSymKind) =
   let obj {.inject.} = s[]
   s[] = TSym(kind: k, itemId: obj.itemId, magic: obj.magic, typ: obj.typ, name: obj.name,
-             info: obj.info, owner: obj.owner, flags: obj.flags, ast: obj.ast,
+             info: obj.info, ownerField: obj.ownerField, flags: obj.flags, ast: obj.ast,
              options: obj.options, position: obj.position, offset: obj.offset,
              loc: obj.loc, annex: obj.annex, constraint: obj.constraint)
   when hasFFI:
@@ -1739,7 +1748,7 @@ template copyNodeImpl(dst, src, processSonsStmt) =
   dst.info = src.info
   when defined(nimsuggest):
     result.endInfo = src.endInfo
-  dst.typ = src.typ
+  dst.typ() = src.typ
   dst.flags = src.flags * PersistentNodeFlags
   dst.comment = src.comment
   when defined(useNodeIds):
diff --git a/compiler/cbuilderdecls.nim b/compiler/cbuilderdecls.nim
index 4185c71826..1c54a85eb3 100644
--- a/compiler/cbuilderdecls.nim
+++ b/compiler/cbuilderdecls.nim
@@ -54,6 +54,32 @@ template addVarWithTypeAndInitializer(builder: var Builder, kind: VarKind = Loca
   initializerBody
   builder.add(";\n")
 
+proc addArrayVar(builder: var Builder, kind: VarKind = Local, name: string, elementType: Snippet, len: int, initializer: Snippet = "") =
+  ## adds an array variable declaration to the builder
+  builder.addVarHeader(kind)
+  builder.add(elementType)
+  builder.add(" ")
+  builder.add(name)
+  builder.add("[")
+  builder.addInt(len)
+  builder.add("]")
+  if initializer.len != 0:
+    builder.add(" = ")
+    builder.add(initializer)
+  builder.add(";\n")
+
+template addArrayVarWithInitializer(builder: var Builder, kind: VarKind = Local, name: string, elementType: Snippet, len: int, body: typed) =
+  ## adds an array variable declaration to the builder with the initializer built according to `body`
+  builder.addVarHeader(kind)
+  builder.add(elementType)
+  builder.add(" ")
+  builder.add(name)
+  builder.add("[")
+  builder.addInt(len)
+  builder.add("] = ")
+  body
+  builder.add(";\n")
+
 template addTypedef(builder: var Builder, name: string, typeBody: typed) =
   ## adds a typedef declaration to the builder with name `name` and type as
   ## built in `typeBody`
@@ -63,41 +89,57 @@ template addTypedef(builder: var Builder, name: string, typeBody: typed) =
   builder.add(name)
   builder.add(";\n")
 
-type StructInitializer = object
-  ## context for building struct initializers, i.e. `{ field1, field2 }`
-  # XXX use in genBracedInit
-  orderCompliant: bool
-    ## if true, fields will not be named, instead values are placed in order
-  needsComma: bool
+type
+  StructInitializerKind = enum
+    siOrderedStruct ## struct constructor, but without named fields on C
+    siNamedStruct ## struct constructor, with named fields i.e. C99 designated initializer
+    siArray ## array constructor
+    siWrapper ## wrapper for a single field, generates it verbatim
 
-proc initStructInitializer(builder: var Builder, orderCompliant: bool): StructInitializer =
-  ## starts building a struct initializer, `orderCompliant = true` means
-  ## built fields must be ordered correctly
-  doAssert orderCompliant, "named struct constructors unimplemented"
-  result = StructInitializer(orderCompliant: true, needsComma: false)
-  builder.add("{ ")
+  StructInitializer = object
+    ## context for building struct initializers, i.e. `{ field1, field2 }`
+    kind: StructInitializerKind
+      ## if true, fields will not be named, instead values are placed in order
+    needsComma: bool
+
+proc initStructInitializer(builder: var Builder, kind: StructInitializerKind): StructInitializer =
+  ## starts building a struct initializer, i.e. braced initializer list
+  result = StructInitializer(kind: kind, needsComma: false)
+  if kind != siWrapper:
+    builder.add("{")
 
 template addField(builder: var Builder, constr: var StructInitializer, name: string, valueBody: typed) =
   ## adds a field to a struct initializer, with the value built in `valueBody`
   if constr.needsComma:
+    assert constr.kind != siWrapper, "wrapper constructor cannot have multiple fields"
     builder.add(", ")
   else:
     constr.needsComma = true
-  if constr.orderCompliant:
+  case constr.kind
+  of siArray, siWrapper:
     # no name, can just add value
     valueBody
-  else:
-    doAssert false, "named struct constructors unimplemented"
+  of siOrderedStruct:
+    # no name, can just add value on C
+    assert name.len != 0, "name has to be given for struct initializer field"
+    valueBody
+  of siNamedStruct:
+    assert name.len != 0, "name has to be given for struct initializer field"
+    builder.add(".")
+    builder.add(name)
+    builder.add(" = ")
+    valueBody
 
 proc finishStructInitializer(builder: var Builder, constr: StructInitializer) =
   ## finishes building a struct initializer
-  builder.add(" }")
+  if constr.kind != siWrapper:
+    builder.add("}")
 
-template addStructInitializer(builder: var Builder, constr: out StructInitializer, orderCompliant: bool, body: typed) =
+template addStructInitializer(builder: var Builder, constr: out StructInitializer, kind: StructInitializerKind, body: typed) =
   ## builds a struct initializer, i.e. `{ field1, field2 }`
   ## a `var StructInitializer` must be declared and passed as a parameter so
   ## that it can be used with `addField`
-  constr = builder.initStructInitializer(orderCompliant)
+  constr = builder.initStructInitializer(kind)
   body
   builder.finishStructInitializer(constr)
 
diff --git a/compiler/cbuilderexprs.nim b/compiler/cbuilderexprs.nim
index 16caaa0215..f381944ecc 100644
--- a/compiler/cbuilderexprs.nim
+++ b/compiler/cbuilderexprs.nim
@@ -15,5 +15,11 @@ const
 proc procPtrType(conv: TCallingConvention, rettype: Snippet, name: string): Snippet =
   CallingConvToStr[conv] & "_PTR(" & rettype & ", " & name & ")"
 
+proc cCast(typ, value: Snippet): Snippet =
+  "((" & typ & ") " & value & ")"
+
+proc cAddr(value: Snippet): Snippet =
+  "&" & value
+
 proc bitOr(a, b: Snippet): Snippet =
-  a & " | " & b
+  "(" & a & " | " & b & ")"
diff --git a/compiler/ccgcalls.nim b/compiler/ccgcalls.nim
index ac607e3ada..788f7a470b 100644
--- a/compiler/ccgcalls.nim
+++ b/compiler/ccgcalls.nim
@@ -336,7 +336,7 @@ proc genArg(p: BProc, n: PNode, param: PSym; call: PNode; result: var Rope; need
     # 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
+      n.typ() = n.typ.exactReplica
       n.typ.flags.incl tfVarIsPtr
     a = initLocExprSingleUse(p, n)
     a = withTmpIfNeeded(p, a, needsTmp)
diff --git a/compiler/ccgexprs.nim b/compiler/ccgexprs.nim
index a344816ba8..c954e6057b 100644
--- a/compiler/ccgexprs.nim
+++ b/compiler/ccgexprs.nim
@@ -13,7 +13,7 @@ when defined(nimCompilerStacktraceHints):
   import std/stackframes
 
 proc getNullValueAuxT(p: BProc; orig, t: PType; obj, constOrNil: PNode,
-                      result: var Rope; count: var int;
+                      result: var Builder; init: var StructInitializer;
                       isConst: bool, info: TLineInfo)
 
 # -------------------------- constant expressions ------------------------
@@ -1626,7 +1626,7 @@ proc genSeqConstr(p: BProc, n: PNode, d: var TLoc) =
 proc genArrToSeq(p: BProc, n: PNode, d: var TLoc) =
   var elem, arr: TLoc
   if n[1].kind == nkBracket:
-    n[1].typ = n.typ
+    n[1].typ() = n.typ
     genSeqConstr(p, n[1], d)
     return
   if d.k == locNone:
@@ -2044,7 +2044,7 @@ proc genInOp(p: BProc, e: PNode, d: var TLoc) =
 
 proc genSetOp(p: BProc, e: PNode, d: var TLoc, op: TMagic) =
   const
-    lookupOpr: array[mLeSet..mMinusSet, string] = [
+    lookupOpr: array[mLeSet..mXorSet, string] = [
       "for ($1 = 0; $1 < $2; $1++) { $n" &
       "  $3 = (($4[$1] & ~ $5[$1]) == 0);$n" &
       "  if (!$3) break;}$n",
@@ -2054,7 +2054,8 @@ proc genSetOp(p: BProc, e: PNode, d: var TLoc, op: TMagic) =
       "if ($3) $3 = (#nimCmpMem($4, $5, $2) != 0);$n",
       "&",
       "|",
-      "& ~"]
+      "& ~",
+      "^"]
   var a, b: TLoc
   var i: TLoc
   var setType = skipTypes(e[1].typ, abstractVar)
@@ -2085,6 +2086,7 @@ proc genSetOp(p: BProc, e: PNode, d: var TLoc, op: TMagic) =
     of mMulSet: binaryExpr(p, e, d, "($1 & $2)")
     of mPlusSet: binaryExpr(p, e, d, "($1 | $2)")
     of mMinusSet: binaryExpr(p, e, d, "($1 & ~ $2)")
+    of mXorSet: binaryExpr(p, e, d, "($1 ^ $2)")
     of mInSet:
       genInOp(p, e, d)
     else: internalError(p.config, e.info, "genSetOp()")
@@ -2112,7 +2114,7 @@ proc genSetOp(p: BProc, e: PNode, d: var TLoc, op: TMagic) =
       var a = initLocExpr(p, e[1])
       var b = initLocExpr(p, e[2])
       putIntoDest(p, d, e, ropecg(p.module, "(#nimCmpMem($1, $2, $3)==0)", [a.rdCharLoc, b.rdCharLoc, size]))
-    of mMulSet, mPlusSet, mMinusSet:
+    of mMulSet, mPlusSet, mMinusSet, mXorSet:
       # we inline the simple for loop for better code generation:
       i = getTemp(p, getSysType(p.module.g.graph, unknownLineInfo, tyInt)) # our counter
       a = initLocExpr(p, e[1])
@@ -2321,7 +2323,7 @@ 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)
+  var a: TLoc = initLocExpr(p, n[1].skipAddr, {lfEnforceDeref})
   if n.len == 4:
     # generated by liftdestructors:
     var src: TLoc = initLocExpr(p, n[2])
@@ -2548,7 +2550,7 @@ proc genMagicExpr(p: BProc, e: PNode, d: var TLoc, op: TMagic) =
   of mSetLengthStr: genSetLengthStr(p, e, d)
   of mSetLengthSeq: genSetLengthSeq(p, e, d)
   of mIncl, mExcl, mCard, mLtSet, mLeSet, mEqSet, mMulSet, mPlusSet, mMinusSet,
-     mInSet:
+     mInSet, mXorSet:
     genSetOp(p, e, d, op)
   of mNewString, mNewStringOfCap, mExit, mParseBiggestFloat:
     var opr = e[0].sym
@@ -3077,7 +3079,7 @@ proc expr(p: BProc, n: PNode, d: var TLoc) =
       # addr ( deref ( x )) --> x
       var x = n[0][0]
       if n.typ.skipTypes(abstractVar).kind != tyOpenArray:
-        x.typ = n.typ
+        x.typ() = n.typ
       expr(p, x, d)
       return
     genAddr(p, n, d)
@@ -3193,7 +3195,7 @@ proc expr(p: BProc, n: PNode, d: var TLoc) =
   of nkMixinStmt, nkBindStmt: discard
   else: internalError(p.config, n.info, "expr(" & $n.kind & "); unknown node kind")
 
-proc getDefaultValue(p: BProc; typ: PType; info: TLineInfo; result: var Rope) =
+proc getDefaultValue(p: BProc; typ: PType; info: TLineInfo; result: var Builder) =
   var t = skipTypes(typ, abstractRange+{tyOwned}-{tyTypeDesc})
   case t.kind
   of tyBool: result.add rope"NIM_FALSE"
@@ -3204,38 +3206,56 @@ proc getDefaultValue(p: BProc; typ: PType; info: TLineInfo; result: var Rope) =
     result.add rope"NIM_NIL"
   of tyString, tySequence:
     if optSeqDestructors in p.config.globalOptions:
-      result.add "{0, NIM_NIL}"
+      var seqInit: StructInitializer
+      result.addStructInitializer(seqInit, kind = siOrderedStruct):
+        result.addField(seqInit, name = "len"):
+          result.add("0")
+        result.addField(seqInit, name = "p"):
+          result.add("NIM_NIL")
     else:
       result.add "NIM_NIL"
   of tyProc:
     if t.callConv != ccClosure:
       result.add "NIM_NIL"
     else:
-      result.add "{NIM_NIL, NIM_NIL}"
+      var closureInit: StructInitializer
+      result.addStructInitializer(closureInit, kind = siOrderedStruct):
+        result.addField(closureInit, name = "ClP_0"):
+          result.add("NIM_NIL")
+        result.addField(closureInit, name = "ClE_0"):
+          result.add("NIM_NIL")
   of tyObject:
-    var count = 0
-    result.add "{"
-    getNullValueAuxT(p, t, t, t.n, nil, result, count, true, info)
-    result.add "}"
+    var objInit: StructInitializer
+    result.addStructInitializer(objInit, kind = siOrderedStruct):
+      getNullValueAuxT(p, t, t, t.n, nil, result, objInit, true, info)
   of tyTuple:
-    result.add "{"
-    if p.vccAndC and t.isEmptyTupleType:
-      result.add "0"
-    for i, a in t.ikids:
-      if i > 0: result.add ", "
-      getDefaultValue(p, a, info, result)
-    result.add "}"
+    var tupleInit: StructInitializer
+    result.addStructInitializer(tupleInit, kind = siOrderedStruct):
+      if p.vccAndC and t.isEmptyTupleType:
+        result.addField(tupleInit, name = "dummy"):
+          result.add "0"
+      for i, a in t.ikids:
+        result.addField(tupleInit, name = "Field" & $i):
+          getDefaultValue(p, a, info, result)
   of tyArray:
-    result.add "{"
-    for i in 0..<toInt(lengthOrd(p.config, t.indexType)):
-      if i > 0: result.add ", "
-      getDefaultValue(p, t.elementType, info, result)
-    result.add "}"
+    var arrInit: StructInitializer
+    result.addStructInitializer(arrInit, kind = siArray):
+      for i in 0..<toInt(lengthOrd(p.config, t.indexType)):
+        result.addField(arrInit, name = ""):
+          getDefaultValue(p, t.elementType, info, result)
     #result = rope"{}"
   of tyOpenArray, tyVarargs:
-    result.add "{NIM_NIL, 0}"
+    var openArrInit: StructInitializer
+    result.addStructInitializer(openArrInit, kind = siOrderedStruct):
+      result.addField(openArrInit, name = "Field0"):
+        result.add("NIM_NIL")
+      result.addField(openArrInit, name = "Field1"):
+        result.add("0")
   of tySet:
-    if mapSetType(p.config, t) == ctArray: result.add "{}"
+    if mapSetType(p.config, t) == ctArray:
+      var setInit: StructInitializer
+      result.addStructInitializer(setInit, kind = siArray):
+        discard
     else: result.add "0"
   else:
     globalError(p.config, info, "cannot create null element for: " & $t.kind)
@@ -3246,16 +3266,18 @@ proc isEmptyCaseObjectBranch(n: PNode): bool =
   return true
 
 proc getNullValueAux(p: BProc; t: PType; obj, constOrNil: PNode,
-                     result: var Rope; count: var int;
+                     result: var Builder; init: var StructInitializer;
                      isConst: bool, info: TLineInfo) =
   case obj.kind
   of nkRecList:
+    let isUnion = tfUnion in t.flags
     for it in obj.sons:
-      getNullValueAux(p, t, it, constOrNil, result, count, isConst, info)
+      getNullValueAux(p, t, it, constOrNil, result, init, isConst, info)
+      if isUnion:
+        # generate only 1 field for default value of union
+        return
   of nkRecCase:
-    getNullValueAux(p, t, obj[0], constOrNil, result, count, isConst, info)
-    var res = ""
-    if count > 0: res.add ", "
+    getNullValueAux(p, t, obj[0], constOrNil, result, init, isConst, info)
     var branch = Zero
     if constOrNil != nil:
       ## find kind value, default is zero if not specified
@@ -3269,140 +3291,186 @@ proc getNullValueAux(p: BProc; t: PType; obj, constOrNil: PNode,
           break
 
     let selectedBranch = caseObjDefaultBranch(obj, branch)
-    res.add "{"
-    var countB = 0
     let b = lastSon(obj[selectedBranch])
     # designated initilization is the only way to init non first element of unions
     # branches are allowed to have no members (b.len == 0), in this case they don't need initializer
+    var fieldName: string = ""
     if b.kind == nkRecList and not isEmptyCaseObjectBranch(b):
-      res.add "._" & mangleRecFieldName(p.module, obj[0].sym) & "_" & $selectedBranch & " = {"
-      getNullValueAux(p, t,  b, constOrNil, res, countB, isConst, info)
-      res.add "}"
+      fieldName = "_" & mangleRecFieldName(p.module, obj[0].sym) & "_" & $selectedBranch
+      result.addField(init, name = "<anonymous union>"):
+        # XXX figure out name for the union, see use of `addAnonUnion`
+        var branchInit: StructInitializer
+        result.addStructInitializer(branchInit, kind = siNamedStruct):
+          result.addField(branchInit, name = fieldName):
+            var branchObjInit: StructInitializer
+            result.addStructInitializer(branchObjInit, kind = siOrderedStruct):
+              getNullValueAux(p, t, b, constOrNil, result, branchObjInit, isConst, info)
     elif b.kind == nkSym:
-      res.add "." & mangleRecFieldName(p.module, b.sym) & " = "
-      getNullValueAux(p, t,  b, constOrNil, res, countB, isConst, info)
+      fieldName = mangleRecFieldName(p.module, b.sym)
+      result.addField(init, name = "<anonymous union>"):
+        # XXX figure out name for the union, see use of `addAnonUnion`
+        var branchInit: StructInitializer
+        result.addStructInitializer(branchInit, kind = siNamedStruct):
+          result.addField(branchInit, name = fieldName):
+            # we need to generate the default value of the single sym,
+            # to do this create a dummy wrapper initializer and recurse
+            var branchFieldInit: StructInitializer
+            result.addStructInitializer(branchFieldInit, kind = siWrapper):
+              getNullValueAux(p, t, b, constOrNil, result, branchFieldInit, isConst, info)
     else:
+      # no fields, don't initialize
       return
-    result.add res
-    result.add "}"
 
   of nkSym:
-    if count > 0: result.add ", "
-    inc count
     let field = obj.sym
-    if constOrNil != nil:
-      for i in 1..<constOrNil.len:
-        if constOrNil[i].kind == nkExprColonExpr:
-          assert constOrNil[i][0].kind == nkSym, "illformed object constr; the field is not a sym"
-          if constOrNil[i][0].sym.name.id == field.name.id:
-            genBracedInit(p, constOrNil[i][1], isConst, field.typ, result)
-            return
-        elif i == field.position:
-          genBracedInit(p, constOrNil[i], isConst, field.typ, result)
-          return
-    # not found, produce default value:
-    getDefaultValue(p, field.typ, info, result)
+    let sname = mangleRecFieldName(p.module, field)
+    result.addField(init, name = sname):
+      block fieldInit:
+        if constOrNil != nil:
+          for i in 1..<constOrNil.len:
+            if constOrNil[i].kind == nkExprColonExpr:
+              assert constOrNil[i][0].kind == nkSym, "illformed object constr; the field is not a sym"
+              if constOrNil[i][0].sym.name.id == field.name.id:
+                genBracedInit(p, constOrNil[i][1], isConst, field.typ, result)
+                break fieldInit
+            elif i == field.position:
+              genBracedInit(p, constOrNil[i], isConst, field.typ, result)
+              break fieldInit
+        # not found, produce default value:
+        getDefaultValue(p, field.typ, info, result)
   else:
     localError(p.config, info, "cannot create null element for: " & $obj)
 
 proc getNullValueAuxT(p: BProc; orig, t: PType; obj, constOrNil: PNode,
-                      result: var Rope; count: var int;
+                      result: var Builder; init: var StructInitializer;
                       isConst: bool, info: TLineInfo) =
   var base = t.baseClass
-  let oldRes = result
-  let oldcount = count
+  when false:
+    let oldRes = result
+    let oldcount = count
   if base != nil:
-    result.add "{"
     base = skipTypes(base, skipPtrs)
-    getNullValueAuxT(p, orig, base, base.n, constOrNil, result, count, isConst, info)
-    result.add "}"
+    result.addField(init, name = "Sup"):
+      var baseInit: StructInitializer
+      result.addStructInitializer(baseInit, kind = siOrderedStruct):
+        getNullValueAuxT(p, orig, base, base.n, constOrNil, result, baseInit, isConst, info)
   elif not isObjLackingTypeField(t):
-    if optTinyRtti in p.config.globalOptions:
-      result.add genTypeInfoV2(p.module, orig, obj.info)
-    else:
-      result.add genTypeInfoV1(p.module, orig, obj.info)
-    inc count
-  getNullValueAux(p, t, obj, constOrNil, result, count, isConst, info)
-  # do not emit '{}' as that is not valid C:
-  if oldcount == count: result = oldRes
+    result.addField(init, name = "m_type"):
+      if optTinyRtti in p.config.globalOptions:
+        result.add genTypeInfoV2(p.module, orig, obj.info)
+      else:
+        result.add genTypeInfoV1(p.module, orig, obj.info)
+  getNullValueAux(p, t, obj, constOrNil, result, init, isConst, info)
+  when false: # referring to Sup field, hopefully not a problem
+    # do not emit '{}' as that is not valid C:
+    if oldcount == count: result = oldRes
 
-proc genConstObjConstr(p: BProc; n: PNode; isConst: bool; result: var Rope) =
+proc genConstObjConstr(p: BProc; n: PNode; isConst: bool; result: var Builder) =
   let t = n.typ.skipTypes(abstractInstOwned)
-  var count = 0
   #if not isObjLackingTypeField(t) and not p.module.compileToCpp:
   #  result.addf("{$1}", [genTypeInfo(p.module, t)])
   #  inc count
-  result.add "{"
-  if t.kind == tyObject:
-    getNullValueAuxT(p, t, t, t.n, n, result, count, isConst, n.info)
-  result.add("}\n")
+  var objInit: StructInitializer
+  result.addStructInitializer(objInit, kind = siOrderedStruct):
+    if t.kind == tyObject:
+      getNullValueAuxT(p, t, t, t.n, n, result, objInit, isConst, n.info)
 
-proc genConstSimpleList(p: BProc, n: PNode; isConst: bool; result: var Rope) =
-  result.add "{"
-  if p.vccAndC and n.len == 0 and n.typ.kind == tyArray:
-    getDefaultValue(p, n.typ.elementType, n.info, result)
-  for i in 0..<n.len:
-    let it = n[i]
-    if i > 0: result.add ",\n"
-    if it.kind == nkExprColonExpr: genBracedInit(p, it[1], isConst, it[0].typ, result)
-    else: genBracedInit(p, it, isConst, it.typ, result)
-  result.add("}\n")
-
-proc genConstTuple(p: BProc, n: PNode; isConst: bool; tup: PType; result: var Rope) =
-  result.add "{"
-  if p.vccAndC and n.len == 0:
-    result.add "0"
-  for i in 0..<n.len:
-    let it = n[i]
-    if i > 0: result.add ",\n"
-    if it.kind == nkExprColonExpr: genBracedInit(p, it[1], isConst, tup[i], result)
-    else: genBracedInit(p, it, isConst, tup[i], result)
-  result.add("}\n")
-
-proc genConstSeq(p: BProc, n: PNode, t: PType; isConst: bool; result: var Rope) =
-  var data = "{{$1, $1 | NIM_STRLIT_FLAG}" % [n.len.rope]
-  let base = t.skipTypes(abstractInst)[0]
-  if n.len > 0:
-    # array part needs extra curlies:
-    data.add(", {")
+proc genConstSimpleList(p: BProc, n: PNode; isConst: bool; result: var Builder) =
+  var arrInit: StructInitializer
+  result.addStructInitializer(arrInit, kind = siArray):
+    if p.vccAndC and n.len == 0 and n.typ.kind == tyArray:
+      result.addField(arrInit, name = ""):
+        getDefaultValue(p, n.typ.elementType, n.info, result)
     for i in 0..<n.len:
-      if i > 0: data.addf(",$n", [])
-      genBracedInit(p, n[i], isConst, base, data)
-    data.add("}")
-  data.add("}")
+      let it = n[i]
+      var ind, val: PNode
+      if it.kind == nkExprColonExpr:
+        ind = it[0]
+        val = it[1]
+      else:
+        ind = it
+        val = it
+      result.addField(arrInit, name = ""):
+        genBracedInit(p, val, isConst, ind.typ, result)
 
+proc genConstTuple(p: BProc, n: PNode; isConst: bool; tup: PType; result: var Builder) =
+  var tupleInit: StructInitializer
+  result.addStructInitializer(tupleInit, kind = siOrderedStruct):
+    if p.vccAndC and n.len == 0:
+      result.addField(tupleInit, name = "dummy"):
+        result.add("0")
+    for i in 0..<n.len:
+      var it = n[i]
+      if it.kind == nkExprColonExpr:
+        it = it[1]
+      result.addField(tupleInit, name = "Field" & $i):
+        genBracedInit(p, it, isConst, tup[i], result)
+
+proc genConstSeq(p: BProc, n: PNode, t: PType; isConst: bool; result: var Builder) =
+  let base = t.skipTypes(abstractInst)[0]
   let tmpName = getTempName(p.module)
 
-  appcg(p.module, cfsStrData,
-        "static $5 struct {$n" &
-        "  #TGenericSeq Sup;$n" &
-        "  $1 data[$2];$n" &
-        "} $3 = $4;$n", [
-        getTypeDesc(p.module, base), n.len, tmpName, data,
-        if isConst: "NIM_CONST" else: ""])
+  var def = newBuilder("")
+  def.addVarWithTypeAndInitializer(
+      if isConst: Const else: Global,
+      name = tmpName):
+    def.addSimpleStruct(p.module, name = "", baseType = ""):
+      def.addField(name = "sup", typ = cgsymValue(p.module, "TGenericSeq"))
+      def.addArrayField(name = "data", elementType = getTypeDesc(p.module, base), len = n.len)
+  do:
+    var structInit: StructInitializer
+    def.addStructInitializer(structInit, kind = siOrderedStruct):
+      def.addField(structInit, name = "sup"):
+        var supInit: StructInitializer
+        def.addStructInitializer(supInit, kind = siOrderedStruct):
+          def.addField(supInit, name = "len"):
+            def.add(n.len.rope)
+          def.addField(supInit, name = "reserved"):
+            def.add(bitOr(rope(n.len), "NIM_STRLIT_FLAG"))
+      if n.len > 0:
+        def.addField(structInit, name = "data"):
+          var arrInit: StructInitializer
+          def.addStructInitializer(arrInit, kind = siArray):
+            for i in 0..<n.len:
+              def.addField(arrInit, name = ""):
+                genBracedInit(p, n[i], isConst, base, def)
+  p.module.s[cfsStrData].add def
 
-  result.add "(($1)&$2)" % [getTypeDesc(p.module, t), tmpName]
+  result.add cCast(typ = getTypeDesc(p.module, t), value = cAddr(tmpName))
 
-proc genConstSeqV2(p: BProc, n: PNode, t: PType; isConst: bool; result: var Rope) =
+proc genConstSeqV2(p: BProc, n: PNode, t: PType; isConst: bool; result: var Builder) =
   let base = t.skipTypes(abstractInst)[0]
-  var data = rope""
-  if n.len > 0:
-    data.add(", {")
-    for i in 0..<n.len:
-      if i > 0: data.addf(",$n", [])
-      genBracedInit(p, n[i], isConst, base, data)
-    data.add("}")
-
   let payload = getTempName(p.module)
-  appcg(p.module, cfsStrData,
-    "static $5 struct {$n" &
-    "  NI cap; $1 data[$2];$n" &
-    "} $3 = {$2 | NIM_STRLIT_FLAG$4};$n", [
-    getTypeDesc(p.module, base), n.len, payload, data,
-    if isConst: "const" else: ""])
-  result.add "{$1, ($2*)&$3}" % [rope(n.len), getSeqPayloadType(p.module, t), payload]
 
-proc genBracedInit(p: BProc, n: PNode; isConst: bool; optionalType: PType; result: var Rope) =
+  var def = newBuilder("")
+  def.addVarWithTypeAndInitializer(
+      if isConst: AlwaysConst else: Global,
+      name = payload):
+    def.addSimpleStruct(p.module, name = "", baseType = ""):
+      def.addField(name = "cap", typ = "NI")
+      def.addArrayField(name = "data", elementType = getTypeDesc(p.module, base), len = n.len)
+  do:
+    var structInit: StructInitializer
+    def.addStructInitializer(structInit, kind = siOrderedStruct):
+      def.addField(structInit, name = "cap"):
+        def.add(bitOr(rope(n.len), "NIM_STRLIT_FLAG"))
+      if n.len > 0:
+        def.addField(structInit, name = "data"):
+          var arrInit: StructInitializer
+          def.addStructInitializer(arrInit, kind = siArray):
+            for i in 0..<n.len:
+              def.addField(arrInit, name = ""):
+                genBracedInit(p, n[i], isConst, base, def)
+  p.module.s[cfsStrData].add def
+
+  var resultInit: StructInitializer
+  result.addStructInitializer(resultInit, kind = siOrderedStruct):
+    result.addField(resultInit, name = "len"):
+      result.add(rope(n.len))
+    result.addField(resultInit, name = "p"):
+      result.add cCast(typ = ptrType(getSeqPayloadType(p.module, t)), value = cAddr(payload))
+
+proc genBracedInit(p: BProc, n: PNode; isConst: bool; optionalType: PType; result: var Builder) =
   case n.kind
   of nkHiddenStdConv, nkHiddenSubConv:
     genBracedInit(p, n[1], isConst, n.typ, result)
@@ -3437,11 +3505,16 @@ proc genBracedInit(p: BProc, n: PNode; isConst: bool; optionalType: PType; resul
         # in VM closures are initialized with nkPar(nkNilLit, nkNilLit)
         # leading to duplicate code like this:
         # "{NIM_NIL,NIM_NIL}, {NIM_NIL,NIM_NIL}"
-        if n[0].kind == nkNilLit:
-          result.add "{NIM_NIL,NIM_NIL}"
-        else:
-          var d: TLoc = initLocExpr(p, n[0])
-          result.add "{(($1) $2),NIM_NIL}" % [getClosureType(p.module, typ, clHalfWithEnv), rdLoc(d)]
+        var closureInit: StructInitializer
+        result.addStructInitializer(closureInit, kind = siOrderedStruct):
+          result.addField(closureInit, name = "ClP_0"):
+            if n[0].kind == nkNilLit:
+              result.add("NIM_NIL")
+            else:
+              var d: TLoc = initLocExpr(p, n[0])
+              result.add(cCast(typ = getClosureType(p.module, typ, clHalfWithEnv), value = rdLoc(d)))
+          result.addField(closureInit, name = "ClE_0"):
+            result.add("NIM_NIL")
       else:
         var d: TLoc = initLocExpr(p, n)
         result.add rdLoc(d)
@@ -3453,17 +3526,21 @@ proc genBracedInit(p: BProc, n: PNode; isConst: bool; optionalType: PType; resul
       if n.kind != nkBracket:
         internalError(p.config, n.info, "const openArray expression is not an array construction")
 
-      var data = newRopeAppender()
-      genConstSimpleList(p, n, isConst, data)
-
       let payload = getTempName(p.module)
       let ctype = getTypeDesc(p.module, typ.elementType)
       let arrLen = n.len
-      appcg(p.module, cfsStrData,
-        "static $5 $1 $3[$2] = $4;$n", [
-        ctype, arrLen, payload, data,
-        if isConst: "const" else: ""])
-      result.add "{($1*)&$2, $3}" % [ctype, payload, rope arrLen]
+      var data = newBuilder("")
+      data.addArrayVarWithInitializer(
+          kind = if isConst: AlwaysConst else: Global,
+          name = payload, elementType = ctype, len = arrLen):
+        genConstSimpleList(p, n, isConst, data)
+      p.module.s[cfsStrData].add(data)
+      var openArrInit: StructInitializer
+      result.addStructInitializer(openArrInit, kind = siOrderedStruct):
+        result.addField(openArrInit, name = "Field0"):
+          result.add(cCast(typ = ptrType(ctype), value = cAddr(payload)))
+        result.addField(openArrInit, name = "Field1"):
+          result.add(rope arrLen)
 
     of tyObject:
       genConstObjConstr(p, n, isConst, result)
diff --git a/compiler/ccgliterals.nim b/compiler/ccgliterals.nim
index 909bacc0aa..477876c9fe 100644
--- a/compiler/ccgliterals.nim
+++ b/compiler/ccgliterals.nim
@@ -36,22 +36,37 @@ proc genStringLiteralDataOnlyV1(m: BModule, s: string; result: var Rope) =
   cgsym(m, "TGenericSeq")
   let tmp = getTempName(m)
   result.add tmp
-  m.s[cfsStrData].addf("STRING_LITERAL($1, $2, $3);$n",
-       [tmp, makeCString(s), rope(s.len)])
+  var res = newBuilder("")
+  res.addVarWithTypeAndInitializer(AlwaysConst, name = tmp):
+    res.addSimpleStruct(m, name = "", baseType = ""):
+      res.addField(name = "Sup", typ = "TGenericSeq")
+      res.addArrayField(name = "data", elementType = "NIM_CHAR", len = s.len + 1)
+  do:
+    var strInit: StructInitializer
+    res.addStructInitializer(strInit, kind = siOrderedStruct):
+      res.addField(strInit, name = "Sup"):
+        var seqInit: StructInitializer
+        res.addStructInitializer(seqInit, kind = siOrderedStruct):
+          res.addField(seqInit, name = "len"):
+            res.add(rope(s.len))
+          res.addField(seqInit, name = "reserved"):
+            res.add(cCast("NI", bitOr(cCast("NU", rope(s.len)), "NIM_STRLIT_FLAG")))
+      res.addField(strInit, name = "data"):
+        res.add(makeCString(s))
+  m.s[cfsStrData].add(res)
 
 proc genStringLiteralV1(m: BModule; n: PNode; result: var Rope) =
   if s.isNil:
-    appcg(m, result, "((#NimStringDesc*) NIM_NIL)", [])
+    result.add(cCast(ptrType(cgsymValue(m, "NimStringDesc")), "NIM_NIL"))
   else:
     let id = nodeTableTestOrSet(m.dataCache, n, m.labels)
+    var name: string = ""
     if id == m.labels:
       # string literal not found in the cache:
-      appcg(m, result, "((#NimStringDesc*) &", [])
-      genStringLiteralDataOnlyV1(m, n.strVal, result)
-      result.add ")"
+      genStringLiteralDataOnlyV1(m, n.strVal, name)
     else:
-      appcg(m, result, "((#NimStringDesc*) &$1$2)",
-                      [m.tmpBase, id])
+      name = m.tmpBase & $id
+    result.add(cCast(ptrType(cgsymValue(m, "NimStringDesc")), cAddr(name)))
 
 # ------ Version 2: destructor based strings and seqs -----------------------
 
@@ -65,7 +80,7 @@ proc genStringLiteralDataOnlyV2(m: BModule, s: string; result: Rope; isConst: bo
       res.addArrayField(name = "data", elementType = "NIM_CHAR", len = s.len + 1)
   do:
     var structInit: StructInitializer
-    res.addStructInitializer(structInit, orderCompliant = true):
+    res.addStructInitializer(structInit, kind = siOrderedStruct):
       res.addField(structInit, name = "cap"):
         res.add(bitOr(rope(s.len), "NIM_STRLIT_FLAG"))
       res.addField(structInit, name = "data"):
@@ -74,22 +89,30 @@ proc genStringLiteralDataOnlyV2(m: BModule, s: string; result: Rope; isConst: bo
 
 proc genStringLiteralV2(m: BModule; n: PNode; isConst: bool; result: var Rope) =
   let id = nodeTableTestOrSet(m.dataCache, n, m.labels)
+  var litName: string
   if id == m.labels:
-    let pureLit = getTempName(m)
-    genStringLiteralDataOnlyV2(m, n.strVal, pureLit, isConst)
-    let tmp = getTempName(m)
-    result.add tmp
     cgsym(m, "NimStrPayload")
     cgsym(m, "NimStringV2")
     # string literal not found in the cache:
-    m.s[cfsStrData].addf("static $4 NimStringV2 $1 = {$2, (NimStrPayload*)&$3};$n",
-          [tmp, rope(n.strVal.len), pureLit, rope(if isConst: "const" else: "")])
+    litName = getTempName(m)
+    genStringLiteralDataOnlyV2(m, n.strVal, litName, isConst)
   else:
-    let tmp = getTempName(m)
-    result.add tmp
-    m.s[cfsStrData].addf("static $4 NimStringV2 $1 = {$2, (NimStrPayload*)&$3};$n",
-          [tmp, rope(n.strVal.len), m.tmpBase & rope(id),
-          rope(if isConst: "const" else: "")])
+    litName = m.tmpBase & $id
+  let tmp = getTempName(m)
+  result.add tmp
+  var res = newBuilder("")
+  res.addVarWithTypeAndInitializer(
+      if isConst: AlwaysConst else: Global,
+      name = tmp):
+    res.add("NimStringV2")
+  do:
+    var strInit: StructInitializer
+    res.addStructInitializer(strInit, kind = siOrderedStruct):
+      res.addField(strInit, name = "len"):
+        res.add(rope(n.strVal.len))
+      res.addField(strInit, name = "p"):
+        res.add(cCast(ptrType("NimStrPayload"), cAddr(litName)))
+  m.s[cfsStrData].add(res)
 
 proc genStringLiteralV2Const(m: BModule; n: PNode; isConst: bool; result: var Rope) =
   let id = nodeTableTestOrSet(m.dataCache, n, m.labels)
@@ -102,7 +125,12 @@ proc genStringLiteralV2Const(m: BModule; n: PNode; isConst: bool; result: var Ro
     genStringLiteralDataOnlyV2(m, n.strVal, pureLit, isConst)
   else:
     pureLit = m.tmpBase & rope(id)
-  result.addf "{$1, (NimStrPayload*)&$2}", [rope(n.strVal.len), pureLit]
+  var strInit: StructInitializer
+  result.addStructInitializer(strInit, kind = siOrderedStruct):
+    result.addField(strInit, name = "len"):
+      result.add(rope(n.strVal.len))
+    result.addField(strInit, name = "p"):
+      result.add(cCast(ptrType("NimStrPayload"), cAddr(pureLit)))
 
 # ------ Version selector ---------------------------------------------------
 
@@ -118,7 +146,7 @@ proc genStringLiteralDataOnly(m: BModule; s: string; info: TLineInfo;
     localError(m.config, info, "cannot determine how to produce code for string literal")
 
 proc genNilStringLiteral(m: BModule; info: TLineInfo; result: var Rope) =
-  appcg(m, result, "((#NimStringDesc*) NIM_NIL)", [])
+  result.add(cCast(ptrType(cgsymValue(m, "NimStringDesc")), "NIM_NIL"))
 
 proc genStringLiteral(m: BModule; n: PNode; result: var Rope) =
   case detectStrVersion(m)
diff --git a/compiler/ccgstmts.nim b/compiler/ccgstmts.nim
index 883108f2cd..5c71086df0 100644
--- a/compiler/ccgstmts.nim
+++ b/compiler/ccgstmts.nim
@@ -279,7 +279,7 @@ proc genGotoVar(p: BProc; value: PNode) =
   else:
     lineF(p, cpsStmts, "goto NIMSTATE_$#;$n", [value.intVal.rope])
 
-proc genBracedInit(p: BProc, n: PNode; isConst: bool; optionalType: PType; result: var Rope)
+proc genBracedInit(p: BProc, n: PNode; isConst: bool; optionalType: PType; result: var Builder)
 
 proc potentialValueInit(p: BProc; v: PSym; value: PNode; result: var Rope) =
   if lfDynamicLib in v.loc.flags or sfThread in v.flags or p.hcrOn:
diff --git a/compiler/ccgtypes.nim b/compiler/ccgtypes.nim
index 53330c3472..2337c70e63 100644
--- a/compiler/ccgtypes.nim
+++ b/compiler/ccgtypes.nim
@@ -340,7 +340,12 @@ proc getSimpleTypeDesc(m: BModule; typ: PType): Rope =
   of tyNil: result = typeNameOrLiteral(m, typ, "void*")
   of tyInt..tyUInt64:
     result = typeNameOrLiteral(m, typ, NumericalTypeToStr[typ.kind])
-  of tyDistinct, tyRange, tyOrdinal: result = getSimpleTypeDesc(m, typ.skipModifier)
+  of tyRange, tyOrdinal: result = getSimpleTypeDesc(m, typ.skipModifier)
+  of tyDistinct:
+    result = getSimpleTypeDesc(m, typ.skipModifier)
+    if isImportedType(typ) and result != "":
+      useHeader(m, typ.sym)
+      result = typ.sym.loc.snippet
   of tyStatic:
     if typ.n != nil: result = getSimpleTypeDesc(m, skipModifier typ)
     else:
@@ -716,6 +721,7 @@ proc genRecordFieldsAux(m: BModule; n: PNode,
       else: internalError(m.config, "genRecordFieldsAux(record case branch)")
     if unionBody.len != 0:
       result.addAnonUnion:
+        # XXX this has to be a named field for NIFC
         result.add(unionBody)
   of nkSym:
     let field = n.sym
@@ -860,7 +866,8 @@ proc getTypeDescAux(m: BModule; origTyp: PType, check: var IntSet; kind: TypeDes
   if t != origTyp and origTyp.sym != nil: useHeader(m, origTyp.sym)
   let sig = hashType(origTyp, m.config)
 
-  result = getTypePre(m, t, sig)
+  # tyDistinct matters if it is an importc type
+  result = getTypePre(m, origTyp.skipTypes(irrelevantForBackend-{tyOwned, tyDistinct}), sig)
   defer: # defer is the simplest in this case
     if isImportedType(t) and not m.typeABICache.containsOrIncl(sig):
       addAbiCheck(m, t, result)
diff --git a/compiler/cgen.nim b/compiler/cgen.nim
index 1032b989eb..5d145288b1 100644
--- a/compiler/cgen.nim
+++ b/compiler/cgen.nim
@@ -97,7 +97,7 @@ proc t(a: TLoc): PType {.inline.} =
 
 proc lodeTyp(t: PType): PNode =
   result = newNode(nkEmpty)
-  result.typ = t
+  result.typ() = t
 
 proc isSimpleConst(typ: PType): bool =
   let t = skipTypes(typ, abstractVar)
diff --git a/compiler/cgmeth.nim b/compiler/cgmeth.nim
index ca97d04944..fe6da1c1eb 100644
--- a/compiler/cgmeth.nim
+++ b/compiler/cgmeth.nim
@@ -55,7 +55,7 @@ proc methodCall*(n: PNode; conf: ConfigRef): PNode =
   # replace ordinary method by dispatcher method:
   let disp = getDispatcher(result[0].sym)
   if disp != nil:
-    result[0].typ = disp.typ
+    result[0].typ() = disp.typ
     result[0].sym = disp
     # change the arguments to up/downcasts to fit the dispatcher's parameters:
     for i in 1..<result.len:
diff --git a/compiler/closureiters.nim b/compiler/closureiters.nim
index 8bdd04ca78..dd6eb986ee 100644
--- a/compiler/closureiters.nim
+++ b/compiler/closureiters.nim
@@ -161,10 +161,6 @@ type
                     # is their finally. For finally it is parent finally. Otherwise -1
     idgen: IdGenerator
     varStates: Table[ItemId, int] # Used to detect if local variable belongs to multiple states
-    stateVarSym: PSym # :state variable. nil if env already introduced by lambdalifting
-      # remove if -d:nimOptIters is default, treating it as always nil
-    nimOptItersEnabled: bool # tracks if -d:nimOptIters is enabled
-      # should be default when issues are fixed, see #24094
 
 const
   nkSkip = {nkEmpty..nkNilLit, nkTemplateDef, nkTypeSection, nkStaticStmt,
@@ -174,11 +170,8 @@ const
   localRequiresLifting = -2
 
 proc newStateAccess(ctx: var Ctx): PNode =
-  if ctx.stateVarSym.isNil:
-    result = rawIndirectAccess(newSymNode(getEnvParam(ctx.fn)),
+  result = rawIndirectAccess(newSymNode(getEnvParam(ctx.fn)),
       getStateField(ctx.g, ctx.fn), ctx.fn.info)
-  else:
-    result = newSymNode(ctx.stateVarSym)
 
 proc newStateAssgn(ctx: var Ctx, toValue: PNode): PNode =
   # Creates state assignment:
@@ -196,22 +189,12 @@ proc newEnvVar(ctx: var Ctx, name: string, typ: PType): PSym =
   result.flags.incl sfNoInit
   assert(not typ.isNil, "Env var needs a type")
 
-  if not ctx.stateVarSym.isNil:
-    # We haven't gone through labmda lifting yet, so just create a local var,
-    # it will be lifted later
-    if ctx.tempVars.isNil:
-      ctx.tempVars = newNodeI(nkVarSection, ctx.fn.info)
-      addVar(ctx.tempVars, newSymNode(result))
-  else:
-    let envParam = getEnvParam(ctx.fn)
-    # let obj = envParam.typ.lastSon
-    result = addUniqueField(envParam.typ.elementType, result, ctx.g.cache, ctx.idgen)
+  let envParam = getEnvParam(ctx.fn)
+  # let obj = envParam.typ.lastSon
+  result = addUniqueField(envParam.typ.elementType, result, ctx.g.cache, ctx.idgen)
 
 proc newEnvVarAccess(ctx: Ctx, s: PSym): PNode =
-  if ctx.stateVarSym.isNil:
-    result = rawIndirectAccess(newSymNode(getEnvParam(ctx.fn)), s, ctx.fn.info)
-  else:
-    result = newSymNode(s)
+  result = rawIndirectAccess(newSymNode(getEnvParam(ctx.fn)), s, ctx.fn.info)
 
 proc newTempVarAccess(ctx: Ctx, s: PSym): PNode =
   result = newSymNode(s, ctx.fn.info)
@@ -263,20 +246,12 @@ proc newTempVarDef(ctx: Ctx, s: PSym, initialValue: PNode): PNode =
     v = ctx.g.emptyNode
   newTree(nkVarSection, newTree(nkIdentDefs, newSymNode(s), ctx.g.emptyNode, v))
 
-proc newEnvVarAsgn(ctx: Ctx, s: PSym, v: PNode): PNode
-
 proc newTempVar(ctx: var Ctx, typ: PType, parent: PNode, initialValue: PNode = nil): PSym =
-  if ctx.nimOptItersEnabled:
-    result = newSym(skVar, getIdent(ctx.g.cache, ":tmpSlLower" & $ctx.tempVarId), ctx.idgen, ctx.fn, ctx.fn.info)
-  else:
-    result = ctx.newEnvVar(":tmpSlLower" & $ctx.tempVarId, typ)
+  result = newSym(skVar, getIdent(ctx.g.cache, ":tmpSlLower" & $ctx.tempVarId), ctx.idgen, ctx.fn, ctx.fn.info)
   inc ctx.tempVarId
   result.typ = typ
   assert(not typ.isNil, "Temp var needs a type")
-  if ctx.nimOptItersEnabled:
-    parent.add(ctx.newTempVarDef(result, initialValue))
-  elif initialValue != nil:
-    parent.add(ctx.newEnvVarAsgn(result, initialValue))
+  parent.add(ctx.newTempVarDef(result, initialValue))
 
 proc hasYields(n: PNode): bool =
   # TODO: This is very inefficient. It traverses the node, looking for nkYieldStmt.
@@ -336,12 +311,12 @@ proc newNullifyCurExc(ctx: var Ctx, info: TLineInfo): PNode =
   let curExc = ctx.newCurExcAccess()
   curExc.info = info
   let nilnode = newNode(nkNilLit)
-  nilnode.typ = curExc.typ
+  nilnode.typ() = curExc.typ
   result = newTree(nkAsgn, curExc, nilnode)
 
 proc newOr(g: ModuleGraph, a, b: PNode): PNode {.inline.} =
   result = newTree(nkCall, newSymNode(g.getSysMagic(a.info, "or", mOr)), a, b)
-  result.typ = g.getSysType(a.info, tyBool)
+  result.typ() = g.getSysType(a.info, tyBool)
   result.info = a.info
 
 proc collectExceptState(ctx: var Ctx, n: PNode): PNode {.inline.} =
@@ -359,7 +334,7 @@ proc collectExceptState(ctx: var Ctx, n: PNode): PNode {.inline.} =
             newSymNode(g.getSysMagic(c.info, "of", mOf)),
             g.callCodegenProc("getCurrentException"),
             c[i])
-          nextCond.typ = ctx.g.getSysType(c.info, tyBool)
+          nextCond.typ() = ctx.g.getSysType(c.info, tyBool)
           nextCond.info = c.info
 
           if cond.isNil:
@@ -455,24 +430,13 @@ proc newTempVarAsgn(ctx: Ctx, s: PSym, v: PNode): PNode =
     result = newTree(nkFastAsgn, ctx.newTempVarAccess(s), v)
     result.info = v.info
 
-proc newEnvVarAsgn(ctx: Ctx, s: PSym, v: PNode): PNode =
-  # unused with -d:nimOptIters
-  if isEmptyType(v.typ):
-    result = v
-  else:
-    result = newTree(nkFastAsgn, ctx.newEnvVarAccess(s), v)
-    result.info = v.info
-
 proc addExprAssgn(ctx: Ctx, output, input: PNode, sym: PSym) =
-  var input = input
   if input.kind == nkStmtListExpr:
     let (st, res) = exprToStmtList(input)
     output.add(st)
-    input = res
-  if ctx.nimOptItersEnabled:
-    output.add(ctx.newTempVarAsgn(sym, input))
+    output.add(ctx.newTempVarAsgn(sym, res))
   else:
-    output.add(ctx.newEnvVarAsgn(sym, input))
+    output.add(ctx.newTempVarAsgn(sym, input))
 
 proc convertExprBodyToAsgn(ctx: Ctx, exprBody: PNode, res: PSym): PNode =
   result = newNodeI(nkStmtList, exprBody.info)
@@ -480,11 +444,11 @@ proc convertExprBodyToAsgn(ctx: Ctx, exprBody: PNode, res: PSym): PNode =
 
 proc newNotCall(g: ModuleGraph; e: PNode): PNode =
   result = newTree(nkCall, newSymNode(g.getSysMagic(e.info, "not", mNot), e.info), e)
-  result.typ = g.getSysType(e.info, tyBool)
+  result.typ() = g.getSysType(e.info, tyBool)
 
 proc boolLit(g: ModuleGraph; info: TLineInfo; value: bool): PNode =
   result = newIntLit(g, info, ord value)
-  result.typ = getSysType(g, info, tyBool)
+  result.typ() = getSysType(g, info, tyBool)
 
 proc captureVar(c: var Ctx, s: PSym) =
   if c.varStates.getOrDefault(s.itemId) != localRequiresLifting:
@@ -522,7 +486,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
 
       result = newNodeI(nkStmtListExpr, n.info)
       if n.typ.isNil: internalError(ctx.g.config, "lowerStmtListExprs: constr typ.isNil")
-      result.typ = n.typ
+      result.typ() = n.typ
 
       for i in 0..<n.len:
         case n[i].kind
@@ -549,7 +513,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
       let isExpr = not isEmptyType(n.typ)
       if isExpr:
         result = newNodeI(nkStmtListExpr, n.info)
-        result.typ = n.typ
+        result.typ() = n.typ
         tmp = ctx.newTempVar(n.typ, result)
       else:
         result = newNodeI(nkStmtList, n.info)
@@ -601,11 +565,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
         else:
           internalError(ctx.g.config, "lowerStmtListExpr(nkIf): " & $branch.kind)
 
-      if isExpr:
-        if ctx.nimOptItersEnabled:
-          result.add(ctx.newTempVarAccess(tmp))
-        else:
-          result.add(ctx.newEnvVarAccess(tmp))
+      if isExpr: result.add(ctx.newTempVarAccess(tmp))
 
   of nkTryStmt, nkHiddenTryStmt:
     var ns = false
@@ -618,7 +578,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
 
       if isExpr:
         result = newNodeI(nkStmtListExpr, n.info)
-        result.typ = n.typ
+        result.typ() = n.typ
         let tmp = ctx.newTempVar(n.typ, result)
 
         n[0] = ctx.convertExprBodyToAsgn(n[0], tmp)
@@ -635,10 +595,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
           else:
             internalError(ctx.g.config, "lowerStmtListExpr(nkTryStmt): " & $branch.kind)
         result.add(n)
-        if ctx.nimOptItersEnabled:
-          result.add(ctx.newTempVarAccess(tmp))
-        else:
-          result.add(ctx.newEnvVarAccess(tmp))
+        result.add(ctx.newTempVarAccess(tmp))
 
   of nkCaseStmt:
     var ns = false
@@ -652,7 +609,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
 
       if isExpr:
         result = newNodeI(nkStmtListExpr, n.info)
-        result.typ = n.typ
+        result.typ() = n.typ
         let tmp = ctx.newTempVar(n.typ, result)
 
         if n[0].kind == nkStmtListExpr:
@@ -670,10 +627,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
           else:
             internalError(ctx.g.config, "lowerStmtListExpr(nkCaseStmt): " & $branch.kind)
         result.add(n)
-        if ctx.nimOptItersEnabled:
-          result.add(ctx.newTempVarAccess(tmp))
-        else:
-          result.add(ctx.newEnvVarAccess(tmp))
+        result.add(ctx.newTempVarAccess(tmp))
       elif n[0].kind == nkStmtListExpr:
         result = newNodeI(nkStmtList, n.info)
         let (st, ex) = exprToStmtList(n[0])
@@ -692,7 +646,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
 
       if isExpr:
         result = newNodeI(nkStmtListExpr, n.info)
-        result.typ = n.typ
+        result.typ() = n.typ
       else:
         result = newNodeI(nkStmtList, n.info)
 
@@ -706,11 +660,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
         let tmp = ctx.newTempVar(cond.typ, result, cond)
         # result.add(ctx.newTempVarAsgn(tmp, cond))
 
-        var check: PNode
-        if ctx.nimOptItersEnabled:
-          check = ctx.newTempVarAccess(tmp)
-        else:
-          check = ctx.newEnvVarAccess(tmp)
+        var check = ctx.newTempVarAccess(tmp)
         if n[0].sym.magic == mOr:
           check = ctx.g.newNotCall(check)
 
@@ -720,18 +670,12 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
           let (st, ex) = exprToStmtList(cond)
           ifBody.add(st)
           cond = ex
-        if ctx.nimOptItersEnabled:
-          ifBody.add(ctx.newTempVarAsgn(tmp, cond))
-        else:
-          ifBody.add(ctx.newEnvVarAsgn(tmp, cond))
+        ifBody.add(ctx.newTempVarAsgn(tmp, cond))
 
         let ifBranch = newTree(nkElifBranch, check, ifBody)
         let ifNode = newTree(nkIfStmt, ifBranch)
         result.add(ifNode)
-        if ctx.nimOptItersEnabled:
-          result.add(ctx.newTempVarAccess(tmp))
-        else:
-          result.add(ctx.newEnvVarAccess(tmp))
+        result.add(ctx.newTempVarAccess(tmp))
       else:
         for i in 0..<n.len:
           if n[i].kind == nkStmtListExpr:
@@ -742,10 +686,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
           if n[i].kind in nkCallKinds: # XXX: This should better be some sort of side effect tracking
             let tmp = ctx.newTempVar(n[i].typ, result, n[i])
             # result.add(ctx.newTempVarAsgn(tmp, n[i]))
-            if ctx.nimOptItersEnabled:
-              n[i] = ctx.newTempVarAccess(tmp)
-            else:
-              n[i] = ctx.newEnvVarAccess(tmp)
+            n[i] = ctx.newTempVarAccess(tmp)
 
         result.add(n)
 
@@ -791,7 +732,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
     if ns:
       needsSplit = true
       result = newNodeI(nkStmtListExpr, n.info)
-      result.typ = n.typ
+      result.typ() = n.typ
       let (st, ex) = exprToStmtList(n[^1])
       result.add(st)
       n[^1] = ex
@@ -861,7 +802,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
     if ns:
       needsSplit = true
       result = newNodeI(nkStmtListExpr, n.info)
-      result.typ = n.typ
+      result.typ() = n.typ
       let (st, ex) = exprToStmtList(n[0])
       result.add(st)
       n[0] = ex
@@ -873,10 +814,10 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
     if ns:
       needsSplit = true
       result = newNodeI(nkStmtListExpr, n.info)
-      result.typ = n.typ
+      result.typ() = n.typ
       let (st, ex) = exprToStmtList(n[1])
       n.transitionSonsKind(nkBlockStmt)
-      n.typ = nil
+      n.typ() = nil
       n[1] = st
       result.add(n)
       result.add(ex)
@@ -897,9 +838,9 @@ proc newEndFinallyNode(ctx: var Ctx, info: TLineInfo): PNode =
   #         raise
   let curExc = ctx.newCurExcAccess()
   let nilnode = newNode(nkNilLit)
-  nilnode.typ = curExc.typ
+  nilnode.typ() = curExc.typ
   let cmp = newTree(nkCall, newSymNode(ctx.g.getSysMagic(info, "==", mEqRef), info), curExc, nilnode)
-  cmp.typ = ctx.g.getSysType(info, tyBool)
+  cmp.typ() = ctx.g.getSysType(info, tyBool)
 
   let retStmt =
     if ctx.nearestFinally == 0:
@@ -1244,11 +1185,11 @@ proc newArrayType(g: ModuleGraph; n: int, t: PType; idgen: IdGenerator; owner: P
 
 proc createExceptionTable(ctx: var Ctx): PNode {.inline.} =
   result = newNodeI(nkBracket, ctx.fn.info)
-  result.typ = ctx.g.newArrayType(ctx.exceptionTable.len, ctx.g.getSysType(ctx.fn.info, tyInt16), ctx.idgen, ctx.fn)
+  result.typ() = ctx.g.newArrayType(ctx.exceptionTable.len, ctx.g.getSysType(ctx.fn.info, tyInt16), ctx.idgen, ctx.fn)
 
   for i in ctx.exceptionTable:
     let elem = newIntNode(nkIntLit, i)
-    elem.typ = ctx.g.getSysType(ctx.fn.info, tyInt16)
+    elem.typ() = ctx.g.getSysType(ctx.fn.info, tyInt16)
     result.add(elem)
 
 proc newCatchBody(ctx: var Ctx, info: TLineInfo): PNode {.inline.} =
@@ -1271,7 +1212,7 @@ proc newCatchBody(ctx: var Ctx, info: TLineInfo): PNode {.inline.} =
     let getNextState = newTree(nkBracketExpr,
       ctx.createExceptionTable(),
       ctx.newStateAccess())
-    getNextState.typ = intTyp
+    getNextState.typ() = intTyp
 
     # :state = exceptionTable[:state]
     result.add(ctx.newStateAssgn(getNextState))
@@ -1282,7 +1223,7 @@ proc newCatchBody(ctx: var Ctx, info: TLineInfo): PNode {.inline.} =
       ctx.g.getSysMagic(info, "==", mEqI).newSymNode(),
       ctx.newStateAccess(),
       newIntTypeNode(0, intTyp))
-    cond.typ = boolTyp
+    cond.typ() = boolTyp
 
     let raiseStmt = newTree(nkRaiseStmt, ctx.g.emptyNode)
     let ifBranch = newTree(nkElifBranch, cond, raiseStmt)
@@ -1295,7 +1236,7 @@ proc newCatchBody(ctx: var Ctx, info: TLineInfo): PNode {.inline.} =
       ctx.g.getSysMagic(info, "<", mLtI).newSymNode,
       newIntTypeNode(0, intTyp),
       ctx.newStateAccess())
-    cond.typ = boolTyp
+    cond.typ() = boolTyp
 
     let asgn = newTree(nkAsgn, ctx.newUnrollFinallyAccess(info), cond)
     result.add(asgn)
@@ -1306,12 +1247,12 @@ proc newCatchBody(ctx: var Ctx, info: TLineInfo): PNode {.inline.} =
       ctx.g.getSysMagic(info, "<", mLtI).newSymNode,
       ctx.newStateAccess(),
       newIntTypeNode(0, intTyp))
-    cond.typ = boolTyp
+    cond.typ() = boolTyp
 
     let negateState = newTree(nkCall,
       ctx.g.getSysMagic(info, "-", mUnaryMinusI).newSymNode,
       ctx.newStateAccess())
-    negateState.typ = intTyp
+    negateState.typ() = intTyp
 
     let ifBranch = newTree(nkElifBranch, cond, ctx.newStateAssgn(negateState))
     let ifStmt = newTree(nkIfStmt, ifBranch)
@@ -1343,13 +1284,6 @@ proc wrapIntoStateLoop(ctx: var Ctx, n: PNode): PNode =
   result.info = n.info
 
   let localVars = newNodeI(nkStmtList, n.info)
-  if not ctx.stateVarSym.isNil:
-    let varSect = newNodeI(nkVarSection, n.info)
-    addVar(varSect, newSymNode(ctx.stateVarSym))
-    localVars.add(varSect)
-
-    if not ctx.tempVars.isNil:
-      localVars.add(ctx.tempVars)
 
   let blockStmt = newNodeI(nkBlockStmt, n.info)
   blockStmt.add(newSymNode(ctx.stateLoopLabel))
@@ -1552,21 +1486,11 @@ proc liftLocals(c: var Ctx, n: PNode): PNode =
       n[i] = liftLocals(c, n[i])
 
 proc transformClosureIterator*(g: ModuleGraph; idgen: IdGenerator; fn: PSym, n: PNode): PNode =
-  var ctx = Ctx(g: g, fn: fn, idgen: idgen,
-    # should be default when issues are fixed, see #24094:
-    nimOptItersEnabled: isDefined(g.config, "nimOptIters"))
+  var ctx = Ctx(g: g, fn: fn, idgen: idgen)
 
-  if getEnvParam(fn).isNil:
-    if ctx.nimOptItersEnabled:
-      # The transformation should always happen after at least partial lambdalifting
-      # is performed, so that the closure iter environment is always created upfront.
-      doAssert(false, "Env param not created before iter transformation")
-    else:
-      # Lambda lifting was not done yet. Use temporary :state sym, which will
-      # be handled specially by lambda lifting. Local temp vars (if needed)
-      # should follow the same logic.
-      ctx.stateVarSym = newSym(skVar, getIdent(ctx.g.cache, ":state"), idgen, fn, fn.info)
-      ctx.stateVarSym.typ = g.createClosureIterStateType(fn, idgen)
+  # The transformation should always happen after at least partial lambdalifting
+  # is performed, so that the closure iter environment is always created upfront.
+  doAssert(getEnvParam(fn) != nil, "Env param not created before iter transformation")
 
   ctx.stateLoopLabel = newSym(skLabel, getIdent(ctx.g.cache, ":stateLoop"), idgen, fn, fn.info)
   var pc = PreprocessContext(finallys: @[], config: g.config, idgen: idgen)
@@ -1592,10 +1516,9 @@ proc transformClosureIterator*(g: ModuleGraph; idgen: IdGenerator; fn: PSym, n:
   let caseDispatcher = newTreeI(nkCaseStmt, n.info,
       ctx.newStateAccess())
 
-  if ctx.nimOptItersEnabled:
-    # Lamdalifting will not touch our locals, it is our responsibility to lift those that
-    # need it.
-    detectCapturedVars(ctx)
+  # Lamdalifting will not touch our locals, it is our responsibility to lift those that
+  # need it.
+  detectCapturedVars(ctx)
 
   for s in ctx.states:
     let body = ctx.transformStateAssignments(s.body)
@@ -1604,8 +1527,7 @@ proc transformClosureIterator*(g: ModuleGraph; idgen: IdGenerator; fn: PSym, n:
   caseDispatcher.add newTreeI(nkElse, n.info, newTreeI(nkReturnStmt, n.info, g.emptyNode))
 
   result = wrapIntoStateLoop(ctx, caseDispatcher)
-  if ctx.nimOptItersEnabled:
-    result = liftLocals(ctx, result)
+  result = liftLocals(ctx, result)
 
   when false:
     echo "TRANSFORM TO STATES: "
diff --git a/compiler/condsyms.nim b/compiler/condsyms.nim
index 5043fc5d4c..81cc40f3f6 100644
--- a/compiler/condsyms.nim
+++ b/compiler/condsyms.nim
@@ -169,3 +169,5 @@ proc initDefines*(symbols: StringTableRef) =
   defineSymbol("nimHasGenericsOpenSym2")
   defineSymbol("nimHasGenericsOpenSym3")
   defineSymbol("nimHasJsNoLambdaLifting")
+  defineSymbol("nimHasDefaultFloatRoundtrip")
+  defineSymbol("nimHasXorSet")
diff --git a/compiler/docgen.nim b/compiler/docgen.nim
index 82f153d0a7..d457528217 100644
--- a/compiler/docgen.nim
+++ b/compiler/docgen.nim
@@ -1320,7 +1320,7 @@ proc documentEffect(cache: IdentCache; n, x: PNode, effectType: TSpecialWord, id
       if t.startsWith("ref "): t = substr(t, 4)
       effects[i] = newIdentNode(getIdent(cache, t), n.info)
       # set the type so that the following analysis doesn't screw up:
-      effects[i].typ = real[i].typ
+      effects[i].typ() = real[i].typ
 
     result = newTreeI(nkExprColonExpr, n.info,
       newIdentNode(getIdent(cache, $effectType), n.info), effects)
diff --git a/compiler/evalffi.nim b/compiler/evalffi.nim
index 9871c81af6..84b51d7a00 100644
--- a/compiler/evalffi.nim
+++ b/compiler/evalffi.nim
@@ -275,7 +275,7 @@ proc unpackObject(conf: ConfigRef, x: pointer, typ: PType, n: PNode): PNode =
   # the nkPar node:
   if n.isNil:
     result = newNode(nkTupleConstr)
-    result.typ = typ
+    result.typ() = typ
     if typ.n.isNil:
       internalError(conf, "cannot unpack unnamed tuple")
     unpackObjectAdd(conf, x, typ.n, result)
@@ -298,7 +298,7 @@ proc unpackObject(conf: ConfigRef, x: pointer, typ: PType, n: PNode): PNode =
 proc unpackArray(conf: ConfigRef, x: pointer, typ: PType, n: PNode): PNode =
   if n.isNil:
     result = newNode(nkBracket)
-    result.typ = typ
+    result.typ() = typ
     newSeq(result.sons, lengthOrd(conf, typ).toInt)
   else:
     result = n
@@ -319,7 +319,7 @@ proc unpack(conf: ConfigRef, x: pointer, typ: PType, n: PNode): PNode =
   template aw(k, v, field: untyped): untyped =
     if n.isNil:
       result = newNode(k)
-      result.typ = typ
+      result.typ() = typ
     else:
       # check we have the right field:
       result = n
@@ -333,12 +333,12 @@ proc unpack(conf: ConfigRef, x: pointer, typ: PType, n: PNode): PNode =
   template setNil() =
     if n.isNil:
       result = newNode(nkNilLit)
-      result.typ = typ
+      result.typ() = typ
     else:
       reset n[]
       result = n
       result[] = TNode(kind: nkNilLit)
-      result.typ = typ
+      result.typ() = typ
 
   template awi(kind, v: untyped): untyped = aw(kind, v, intVal)
   template awf(kind, v: untyped): untyped = aw(kind, v, floatVal)
@@ -427,7 +427,7 @@ proc fficast*(conf: ConfigRef, x: PNode, destTyp: PType): PNode =
     # cast through a pointer needs a new inner object:
     let y = if x.kind == nkRefTy: newNodeI(nkRefTy, x.info, 1)
             else: x.copyTree
-    y.typ = x.typ
+    y.typ() = x.typ
     result = unpack(conf, a, destTyp, y)
     dealloc a
 
@@ -481,7 +481,7 @@ proc callForeignFunction*(conf: ConfigRef, fn: PNode, fntyp: PType,
     if aTyp.isNil:
       internalAssert conf, i+1 < fntyp.len
       aTyp = fntyp[i+1]
-      args[i+start].typ = aTyp
+      args[i+start].typ() = aTyp
     sig[i] = mapType(conf, aTyp)
     if sig[i].isNil: globalError(conf, info, "cannot map FFI type")
 
diff --git a/compiler/evaltempl.nim b/compiler/evaltempl.nim
index 77c136d632..33916385b1 100644
--- a/compiler/evaltempl.nim
+++ b/compiler/evaltempl.nim
@@ -64,7 +64,7 @@ proc evalTemplateAux(templ, actual: PNode, c: var TemplCtx, result: PNode) =
         if x == nil:
           x = copySym(s, c.idgen)
           # sem'check needs to set the owner properly later, see bug #9476
-          x.owner = nil # c.genSymOwner
+          setOwner(x, nil) # c.genSymOwner
           #if x.kind == skParam and x.owner.kind == skModule:
           #  internalAssert c.config, false
           idTablePut(c.mapping, s, x)
@@ -182,7 +182,7 @@ proc wrapInComesFrom*(info: TLineInfo; sym: PSym; res: PNode): PNode =
     d.add newSymNode(sym, info)
     result.add d
     result.add res
-    result.typ = res.typ
+    result.typ() = res.typ
 
 proc evalTemplate*(n: PNode, tmpl, genSymOwner: PSym;
                    conf: ConfigRef;
diff --git a/compiler/guards.nim b/compiler/guards.nim
index 553cc744df..15922b3442 100644
--- a/compiler/guards.nim
+++ b/compiler/guards.nim
@@ -1104,7 +1104,7 @@ proc settype(n: PNode): PType =
 
 proc buildOf(it, loc: PNode; o: Operators): PNode =
   var s = newNodeI(nkCurly, it.info, it.len-1)
-  s.typ = settype(loc)
+  s.typ() = settype(loc)
   for i in 0..<it.len-1: s[i] = it[i]
   result = newNodeI(nkCall, it.info, 3)
   result[0] = newSymNode(o.opContains)
@@ -1170,7 +1170,7 @@ proc buildProperFieldCheck(access, check: PNode; o: Operators): PNode =
       # set field name to discriminator field name
       a[1] = check[2]
       # set discriminator field type: important for `neg`
-      a.typ = check[2].typ
+      a.typ() = check[2].typ
       result[2] = a
       # 'access.kind != nkDotExpr' can happen for object constructors
       # which we don't check yet
diff --git a/compiler/ic/ic.nim b/compiler/ic/ic.nim
index 8e81633efe..ecc6069e75 100644
--- a/compiler/ic/ic.nim
+++ b/compiler/ic/ic.nim
@@ -838,7 +838,7 @@ proc loadNodes*(c: var PackedDecoder; g: var PackedModuleGraph; thisModule: int;
   of nkSym:
     result.sym = loadSym(c, g, thisModule, PackedItemId(module: LitId(0), item: tree[n].soperand))
     if result.typ == nil:
-      result.typ = result.sym.typ
+      result.typ() = result.sym.typ
   of externIntLit:
     result.intVal = g[thisModule].fromDisk.numbers[n.litId]
   of nkStrLit..nkTripleStrLit:
@@ -852,7 +852,7 @@ proc loadNodes*(c: var PackedDecoder; g: var PackedModuleGraph; thisModule: int;
     transitionNoneToSym(result)
     result.sym = loadSym(c, g, thisModule, PackedItemId(module: n1.litId, item: tree[n2].soperand))
     if result.typ == nil:
-      result.typ = result.sym.typ
+      result.typ() = result.sym.typ
   else:
     for n0 in sonsReadonly(tree, n):
       result.addAllowNil loadNodes(c, g, thisModule, tree, n0)
@@ -942,7 +942,7 @@ proc symBodyFromPacked(c: var PackedDecoder; g: var PackedModuleGraph;
     result.guard = loadSym(c, g, si, s.guard)
     result.bitsize = s.bitsize
     result.alignment = s.alignment
-  result.owner = loadSym(c, g, si, s.owner)
+  setOwner(result, loadSym(c, g, si, s.owner))
   let externalName = g[si].fromDisk.strings[s.externalName]
   if externalName != "":
     result.loc.snippet = externalName
@@ -998,7 +998,7 @@ proc typeHeaderFromPacked(c: var PackedDecoder; g: var PackedModuleGraph;
 proc typeBodyFromPacked(c: var PackedDecoder; g: var PackedModuleGraph;
                         t: PackedType; si, item: int32; result: PType) =
   result.sym = loadSym(c, g, si, t.sym)
-  result.owner = loadSym(c, g, si, t.owner)
+  setOwner(result, loadSym(c, g, si, t.owner))
   when false:
     for op, item in pairs t.attachedOps:
       result.attachedOps[op] = loadSym(c, g, si, item)
@@ -1062,7 +1062,7 @@ proc setupLookupTables(g: var PackedModuleGraph; conf: ConfigRef; cache: IdentCa
                   name: getIdent(cache, splitFile(filename).name),
                   info: newLineInfo(fileIdx, 1, 1),
                   position: int(fileIdx))
-  m.module.owner = getPackage(conf, cache, fileIdx)
+  setOwner(m.module, getPackage(conf, cache, fileIdx))
   m.module.flags = m.fromDisk.moduleFlags
 
 proc loadToReplayNodes(g: var PackedModuleGraph; conf: ConfigRef; cache: IdentCache;
diff --git a/compiler/injectdestructors.nim b/compiler/injectdestructors.nim
index 3dcc364a31..e6b6d5b42a 100644
--- a/compiler/injectdestructors.nim
+++ b/compiler/injectdestructors.nim
@@ -332,7 +332,7 @@ proc genMarkCyclic(c: var Con; result, dest: PNode) =
         result.add callCodegenProc(c.graph, "nimMarkCyclic", dest.info, dest)
       else:
         let xenv = genBuiltin(c.graph, c.idgen, mAccessEnv, "accessEnv", dest)
-        xenv.typ = getSysType(c.graph, dest.info, tyPointer)
+        xenv.typ() = getSysType(c.graph, dest.info, tyPointer)
         result.add callCodegenProc(c.graph, "nimMarkCyclic", dest.info, xenv)
 
 proc genCopyNoCheck(c: var Con; dest, ri: PNode; a: TTypeAttachedOp): PNode =
@@ -408,7 +408,7 @@ proc genWasMoved(c: var Con, n: PNode): PNode =
 proc genDefaultCall(t: PType; c: Con; info: TLineInfo): PNode =
   result = newNodeI(nkCall, info)
   result.add(newSymNode(createMagic(c.graph, c.idgen, "default", mDefault)))
-  result.typ = t
+  result.typ() = t
 
 proc destructiveMoveVar(n: PNode; c: var Con; s: var Scope): PNode =
   # generate: (let tmp = v; reset(v); tmp)
@@ -822,9 +822,9 @@ proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSing
           n[1].typ.skipTypes(abstractInst-{tyOwned}).kind == tyOwned:
         # allow conversions from owned to unowned via this little hack:
         let nTyp = n[1].typ
-        n[1].typ = n.typ
+        n[1].typ() = n.typ
         result[1] = p(n[1], c, s, sinkArg)
-        result[1].typ = nTyp
+        result[1].typ() = nTyp
       else:
         result[1] = p(n[1], c, s, sinkArg)
     elif n.kind in {nkObjDownConv, nkObjUpConv}:
@@ -1022,9 +1022,9 @@ proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSing
           n[1].typ.skipTypes(abstractInst-{tyOwned}).kind == tyOwned:
         # allow conversions from owned to unowned via this little hack:
         let nTyp = n[1].typ
-        n[1].typ = n.typ
+        n[1].typ() = n.typ
         result[1] = p(n[1], c, s, mode)
-        result[1].typ = nTyp
+        result[1].typ() = nTyp
       else:
         result[1] = p(n[1], c, s, mode)
 
diff --git a/compiler/jsgen.nim b/compiler/jsgen.nim
index 713944defb..21781efde0 100644
--- a/compiler/jsgen.nim
+++ b/compiler/jsgen.nim
@@ -1592,7 +1592,7 @@ proc genAddr(p: PProc, n: PNode, r: var TCompRes) =
       if n.kind == nkHiddenAddr:
         x = n[0][0]
         if n.typ.skipTypes(abstractVar).kind != tyOpenArray:
-          x.typ = n.typ
+          x.typ() = n.typ
       gen(p, x, r)
     of nkHiddenAddr:
       gen(p, n[0], r)
@@ -2458,6 +2458,7 @@ proc genMagic(p: PProc, n: PNode, r: var TCompRes) =
   of mMulSet: binaryExpr(p, n, r, "SetMul", "SetMul($1, $2)")
   of mPlusSet: binaryExpr(p, n, r, "SetPlus", "SetPlus($1, $2)")
   of mMinusSet: binaryExpr(p, n, r, "SetMinus", "SetMinus($1, $2)")
+  of mXorSet: binaryExpr(p, n, r, "SetXor", "SetXor($1, $2)")
   of mIncl: binaryExpr(p, n, r, "", "$1[$2] = true")
   of mExcl: binaryExpr(p, n, r, "", "delete $1[$2]")
   of mInSet:
diff --git a/compiler/lambdalifting.nim b/compiler/lambdalifting.nim
index 54cdfc5bc0..640bb4b2f8 100644
--- a/compiler/lambdalifting.nim
+++ b/compiler/lambdalifting.nim
@@ -150,7 +150,7 @@ template isIterator*(owner: PSym): bool =
 
 proc createEnvObj(g: ModuleGraph; idgen: IdGenerator; owner: PSym; info: TLineInfo): PType =
   result = createObj(g, idgen, owner, info, final=false)
-  if owner.isIterator or not isDefined(g.config, "nimOptIters"):
+  if owner.isIterator:
     rawAddField(result, createStateField(g, owner, idgen))
 
 proc getClosureIterResult*(g: ModuleGraph; iter: PSym; idgen: IdGenerator): PSym =
@@ -175,6 +175,7 @@ proc addHiddenParam(routine: PSym, param: PSym) =
   #echo "produced environment: ", param.id, " for ", routine.id
 
 proc getEnvParam*(routine: PSym): PSym =
+  if routine.ast.isNil: 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:
@@ -228,13 +229,6 @@ proc makeClosure*(g: ModuleGraph; idgen: IdGenerator; prc: PSym; env: PNode; inf
   if tfHasAsgn in result.typ.flags or optSeqDestructors in g.config.globalOptions:
     prc.flags.incl sfInjectDestructors
 
-proc interestingIterVar(s: PSym): bool {.inline.} =
-  # unused with -d:nimOptIters
-  # XXX optimization: Only lift the variable if it lives across
-  # yield/return boundaries! This can potentially speed up
-  # closure iterators quite a bit.
-  result = s.kind in {skResult, skVar, skLet, skTemp, skForVar} and sfGlobal notin s.flags
-
 template liftingHarmful(conf: ConfigRef; owner: PSym): bool =
   ## lambda lifting can be harmful for JS-like code generators.
   let isCompileTime = sfCompileTime in owner.flags or owner.kind == skMacro
@@ -281,16 +275,6 @@ proc liftIterSym*(g: ModuleGraph; n: PNode; idgen: IdGenerator; owner: PSym): PN
   createTypeBoundOpsLL(g, env.typ, n.info, idgen, owner)
   result.add makeClosure(g, idgen, iter, env, n.info)
 
-proc freshVarForClosureIter*(g: ModuleGraph; s: PSym; idgen: IdGenerator; owner: PSym): PNode =
-  # unused with -d:nimOptIters
-  let envParam = getHiddenParam(g, owner)
-  let obj = envParam.typ.skipTypes({tyOwned, tyRef, tyPtr})
-  let field = addField(obj, s, g.cache, idgen)
-
-  var access = newSymNode(envParam)
-  assert obj.kind == tyObject
-  result = rawIndirectAccess(access, field, s.info)
-
 # ------------------ new stuff -------------------------------------------
 
 proc markAsClosure(g: ModuleGraph; owner: PSym; n: PNode) =
@@ -339,7 +323,7 @@ proc getEnvTypeForOwner(c: var DetectionPass; owner: PSym;
   result = c.ownerToType.getOrDefault(owner.id)
   if result.isNil:
     let env = getEnvParam(owner)
-    if env.isNil or not owner.isIterator or not isDefined(c.graph.config, "nimOptIters"):
+    if env.isNil or not owner.isIterator:
       result = newType(tyRef, c.idgen, owner)
       let obj = createEnvObj(c.graph, c.idgen, owner, info)
       rawAddSon(result, obj)
@@ -436,6 +420,12 @@ proc addClosureParam(c: var DetectionPass; fn: PSym; info: TLineInfo) =
     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 =
+  let cp = getEnvParam(iter)
+  doAssert(cp != nil, "Env param not present in iter")
+  let upField = lookupInRecord(cp.typ.skipTypes({tyOwned, tyRef, tyPtr}).n, getIdent(g.cache, upName))
+  upField != nil
+
 proc detectCapturedVars(n: PNode; owner: PSym; c: var DetectionPass) =
   case n.kind
   of nkSym:
@@ -454,23 +444,12 @@ proc detectCapturedVars(n: PNode; owner: PSym; c: var DetectionPass) =
         let body = transformBody(c.graph, c.idgen, s, {useCache})
         detectCapturedVars(body, s, c)
     let ow = s.skipGenericOwner
-    let innerClosure = innerProc and s.typ.callConv == ccClosure and not s.isIterator
+    let innerClosure = innerProc and s.typ.callConv == ccClosure and (not s.isIterator or iterEnvHasUpField(c.graph, s))
     let interested = interestingVar(s)
     if ow == owner:
       if owner.isIterator:
         c.somethingToDo = true
         addClosureParam(c, owner, n.info)
-        if not isDefined(c.graph.config, "nimOptIters") and interestingIterVar(s):
-          if not c.capturedVars.contains(s.id):
-            if not c.inTypeOf: c.capturedVars.incl(s.id)
-            let obj = getHiddenParam(c.graph, owner).typ.skipTypes({tyOwned, tyRef, tyPtr})
-            #let obj = c.getEnvTypeForOwner(s.owner).skipTypes({tyOwned, tyRef, tyPtr})
-
-            if s.name.id == getIdent(c.graph.cache, ":state").id:
-              obj.n[0].sym.flags.incl sfNoInit
-              obj.n[0].sym.itemId = ItemId(module: s.itemId.module, item: -s.itemId.item)
-            else:
-              discard addField(obj, s, c.graph.cache, c.idgen)
     # direct or indirect dependency:
     elif innerClosure or interested:
       discard """
@@ -630,7 +609,7 @@ proc rawClosureCreation(owner: PSym;
       let unowned = c.unownedEnvVars[owner.id]
       assert unowned != nil
       let env2 = copyTree(env)
-      env2.typ = unowned.typ
+      env2.typ() = unowned.typ
       result.add newAsgnStmt(unowned, env2, env.info)
       createTypeBoundOpsLL(d.graph, unowned.typ, env.info, d.idgen, owner)
 
@@ -670,16 +649,27 @@ proc finishClosureCreation(owner: PSym; d: var DetectionPass; c: LiftingPass;
     res.add newAsgnStmt(unowned, nilLit, info)
     createTypeBoundOpsLL(d.graph, unowned.typ, info, d.idgen, owner)
 
-proc closureCreationForIter(iter: PNode;
+proc getUpForIter(g: ModuleGraph; owner, iterOwner: PSym, expectedUpTyp: PType): PNode =
+  var p = getHiddenParam(g, owner)
+  var res = p.newSymNode
+  while res.typ.skipTypes({tyOwned, tyRef, tyPtr}) != expectedUpTyp:
+    let upField = lookupInRecord(p.typ.skipTypes({tyOwned, tyRef, tyPtr}).n, getIdent(g.cache, upName))
+    if upField == nil:
+      return nil
+    p = upField
+    res = rawIndirectAccess(res, upField, p.info)
+  res
+
+proc closureCreationForIter(owner: PSym, iter: PNode;
                             d: var DetectionPass; c: var LiftingPass): PNode =
   result = newNodeIT(nkStmtListExpr, iter.info, iter.sym.typ)
-  let owner = iter.sym.skipGenericOwner
-  var v = newSym(skVar, getIdent(d.graph.cache, envName), d.idgen, owner, iter.info)
+  let iterOwner = iter.sym.skipGenericOwner
+  var v = newSym(skVar, getIdent(d.graph.cache, envName), d.idgen, iterOwner, iter.info)
   incl(v.flags, sfShadowed)
   v.typ = asOwnedRef(d, getHiddenParam(d.graph, iter.sym).typ)
   var vnode: PNode
-  if owner.isIterator:
-    let it = getHiddenParam(d.graph, owner)
+  if iterOwner.isIterator:
+    let it = getHiddenParam(d.graph, iterOwner)
     addUniqueField(it.typ.skipTypes({tyOwned, tyRef, tyPtr}), v, d.graph.cache, d.idgen)
     vnode = indirectAccess(newSymNode(it), v, v.info)
   else:
@@ -688,12 +678,14 @@ proc closureCreationForIter(iter: PNode;
     addVar(vs, vnode)
     result.add(vs)
   result.add genCreateEnv(vnode)
-  createTypeBoundOpsLL(d.graph, vnode.typ, iter.info, d.idgen, owner)
+  createTypeBoundOpsLL(d.graph, vnode.typ, iter.info, d.idgen, iterOwner)
 
   let upField = lookupInRecord(v.typ.skipTypes({tyOwned, tyRef, tyPtr}).n, getIdent(d.graph.cache, upName))
   if upField != nil:
-    let u = setupEnvVar(owner, d, c, iter.info)
-    if u.typ.skipTypes({tyOwned, tyRef, tyPtr}) == upField.typ.skipTypes({tyOwned, tyRef, tyPtr}):
+    let expectedUpTyp = upField.typ.skipTypes({tyOwned, tyRef, tyPtr})
+    let u = if iterOwner == owner: setupEnvVar(iterOwner, d, c, iter.info)
+            else: getUpForIter(d.graph, owner, iterOwner, expectedUpTyp)
+    if u != nil and u.typ.skipTypes({tyOwned, tyRef, tyPtr}) == expectedUpTyp:
       result.add(newAsgnStmt(rawIndirectAccess(vnode, upField, iter.info),
                  u, iter.info))
     else:
@@ -727,7 +719,7 @@ proc symToClosure(n: PNode; owner: PSym; d: var DetectionPass;
     let available = getHiddenParam(d.graph, owner)
     result = makeClosure(d.graph, d.idgen, s, available.newSymNode, n.info)
   elif s.isIterator:
-    result = closureCreationForIter(n, d, c)
+    result = closureCreationForIter(owner, n, d, c)
   elif s.skipGenericOwner == owner:
     # direct dependency, so use the outer's env variable:
     result = makeClosure(d.graph, d.idgen, s, setupEnvVar(owner, d, c, n.info), n.info)
@@ -774,8 +766,6 @@ proc liftCapturedVars(n: PNode; owner: PSym; d: var DetectionPass;
     elif s.id in d.capturedVars:
       if s.owner != owner:
         result = accessViaEnvParam(d.graph, n, owner)
-      elif owner.isIterator and not isDefined(d.graph.config, "nimOptIters") and interestingIterVar(s):
-        result = accessViaEnvParam(d.graph, n, owner)
       else:
         result = accessViaEnvVar(n, owner, d, c)
   of nkEmpty..pred(nkSym), succ(nkSym)..nkNilLit, nkComesFrom,
@@ -796,7 +786,7 @@ proc liftCapturedVars(n: PNode; owner: PSym; d: var DetectionPass;
       let oldInContainer = c.inContainer
       c.inContainer = 0
       let m = newSymNode(n[namePos].sym)
-      m.typ = n.typ
+      m.typ() = n.typ
       result = liftCapturedVars(m, owner, d, c)
       c.inContainer = oldInContainer
   of nkHiddenStdConv:
@@ -893,7 +883,7 @@ proc liftLambdas*(g: ModuleGraph; fn: PSym, body: PNode; tooEarly: var bool;
     # ignore forward declaration:
     result = body
     tooEarly = true
-    if fn.isIterator and isDefined(g.config, "nimOptIters"):
+    if fn.isIterator:
       var d = initDetectionPass(g, fn, idgen)
       addClosureParam(d, fn, body.info)
   else:
diff --git a/compiler/liftdestructors.nim b/compiler/liftdestructors.nim
index 9ff5c0a9d5..69d457a566 100644
--- a/compiler/liftdestructors.nim
+++ b/compiler/liftdestructors.nim
@@ -49,7 +49,7 @@ proc at(a, i: PNode, elemType: PType): PNode =
   result = newNodeI(nkBracketExpr, a.info, 2)
   result[0] = a
   result[1] = i
-  result.typ = elemType
+  result.typ() = elemType
 
 proc destructorOverridden(g: ModuleGraph; t: PType): bool =
   let op = getAttachedOp(g, t, attachedDestructor)
@@ -68,7 +68,7 @@ proc dotField(x: PNode, f: PSym): PNode =
   else:
     result[0] = x
   result[1] = newSymNode(f, x.info)
-  result.typ = f.typ
+  result.typ() = f.typ
 
 proc newAsgnStmt(le, ri: PNode): PNode =
   result = newNodeI(nkAsgn, le.info, 2)
@@ -88,7 +88,7 @@ proc defaultOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
     body.add newAsgnStmt(x, y)
   elif c.kind == attachedDestructor and c.addMemReset:
     let call = genBuiltin(c, mDefault, "default", x)
-    call.typ = t
+    call.typ() = t
     body.add newAsgnStmt(x, call)
   elif c.kind == attachedWasMoved:
     body.add genBuiltin(c, mWasMoved, "`=wasMoved`", x)
@@ -105,7 +105,7 @@ proc genWhileLoop(c: var TLiftCtx; i, dest: PNode): PNode =
   result = newNodeI(nkWhileStmt, c.info, 2)
   let cmp = genBuiltin(c, mLtI, "<", i)
   cmp.add genLen(c.g, dest)
-  cmp.typ = getSysType(c.g, c.info, tyBool)
+  cmp.typ() = getSysType(c.g, c.info, tyBool)
   result[0] = cmp
   result[1] = newNodeI(nkStmtList, c.info)
 
@@ -127,10 +127,10 @@ proc genContainerOf(c: var TLiftCtx; objType: PType, field, x: PSym): PNode =
   dotExpr.add newSymNode(field)
 
   let offsetOf = genBuiltin(c, mOffsetOf, "offsetof", dotExpr)
-  offsetOf.typ = intType
+  offsetOf.typ() = intType
 
   let minusExpr = genBuiltin(c, mSubI, "-", castExpr1)
-  minusExpr.typ = intType
+  minusExpr.typ() = intType
   minusExpr.add offsetOf
 
   let objPtr = makePtrType(objType.owner, objType, c.idgen)
@@ -265,7 +265,7 @@ proc fillBodyObjT(c: var TLiftCtx; t: PType, body, x, y: PNode) =
       # because the wasMoved(dest) call would zero out src, if dest aliases src.
       var cond = newTree(nkCall, newSymNode(c.g.getSysMagic(c.info, "==", mEqRef)),
         newTreeIT(nkAddr, c.info, makePtrType(c.fn, x.typ, c.idgen), x), newTreeIT(nkAddr, c.info, makePtrType(c.fn, y.typ, c.idgen), y))
-      cond.typ = getSysType(c.g, x.info, tyBool)
+      cond.typ() = getSysType(c.g, x.info, tyBool)
       body.add genIf(c, cond, newTreeI(nkReturnStmt, c.info, newNodeI(nkEmpty, c.info)))
     var temp = newSym(skTemp, getIdent(c.g.cache, lowerings.genPrefix), c.idgen, c.fn, c.info)
     temp.typ = x.typ
@@ -296,7 +296,7 @@ proc fillBodyObjT(c: var TLiftCtx; t: PType, body, x, y: PNode) =
 
 proc boolLit*(g: ModuleGraph; info: TLineInfo; value: bool): PNode =
   result = newIntLit(g, info, ord value)
-  result.typ = getSysType(g, info, tyBool)
+  result.typ() = getSysType(g, info, tyBool)
 
 proc getCycleParam(c: TLiftCtx): PNode =
   assert c.kind in {attachedAsgn, attachedDup}
@@ -545,18 +545,18 @@ proc newSeqCall(c: var TLiftCtx; x, y: PNode): PNode =
   # don't call genAddr(c, x) here:
   result = genBuiltin(c, mNewSeq, "newSeq", x)
   let lenCall = genBuiltin(c, mLengthSeq, "len", y)
-  lenCall.typ = getSysType(c.g, x.info, tyInt)
+  lenCall.typ() = getSysType(c.g, x.info, tyInt)
   result.add lenCall
 
 proc setLenStrCall(c: var TLiftCtx; x, y: PNode): PNode =
   let lenCall = genBuiltin(c, mLengthStr, "len", y)
-  lenCall.typ = getSysType(c.g, x.info, tyInt)
+  lenCall.typ() = getSysType(c.g, x.info, tyInt)
   result = genBuiltin(c, mSetLengthStr, "setLen", x) # genAddr(g, x))
   result.add lenCall
 
 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)
+  lenCall.typ() = getSysType(c.g, x.info, tyInt)
   var op = getSysMagic(c.g, x.info, "setLen", mSetLengthSeq)
   op = instantiateGeneric(c, op, t, t)
   result = newTree(nkCall, newSymNode(op, x.info), x, lenCall)
@@ -579,7 +579,7 @@ proc checkSelfAssignment(c: var TLiftCtx; t: PType; body, x, y: PNode) =
       newTreeIT(nkAddr, c.info, makePtrType(c.fn, x.typ, c.idgen), x),
       newTreeIT(nkAddr, c.info, makePtrType(c.fn, y.typ, c.idgen), y)
       )
-  cond.typ = getSysType(c.g, c.info, tyBool)
+  cond.typ() = getSysType(c.g, c.info, tyBool)
   body.add genIf(c, cond, newTreeI(nkReturnStmt, c.info, newNodeI(nkEmpty, c.info)))
 
 proc fillSeqOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
@@ -720,7 +720,7 @@ proc atomicRefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   if isFinal(elemType):
     addDestructorCall(c, elemType, actions, genDeref(tmp, nkDerefExpr))
     var alignOf = genBuiltin(c, mAlignOf, "alignof", newNodeIT(nkType, c.info, elemType))
-    alignOf.typ = getSysType(c.g, c.info, tyInt)
+    alignOf.typ() = getSysType(c.g, c.info, tyInt)
     actions.add callCodegenProc(c.g, "nimRawDispose", c.info, tmp, alignOf)
   else:
     addDestructorCall(c, elemType, newNodeI(nkStmtList, c.info), genDeref(tmp, nkDerefExpr))
@@ -730,7 +730,7 @@ proc atomicRefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   if isCyclic:
     if isFinal(elemType):
       let typInfo = genBuiltin(c, mGetTypeInfoV2, "getTypeInfoV2", newNodeIT(nkType, x.info, elemType))
-      typInfo.typ = getSysType(c.g, c.info, tyPointer)
+      typInfo.typ() = getSysType(c.g, c.info, tyPointer)
       cond = callCodegenProc(c.g, "nimDecRefIsLastCyclicStatic", c.info, tmp, typInfo)
     else:
       cond = callCodegenProc(c.g, "nimDecRefIsLastCyclicDyn", c.info, tmp)
@@ -738,7 +738,7 @@ proc atomicRefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
     cond = callCodegenProc(c.g, "nimDecRefIsLastDyn", c.info, x)
   else:
     cond = callCodegenProc(c.g, "nimDecRefIsLast", c.info, x)
-  cond.typ = getSysType(c.g, x.info, tyBool)
+  cond.typ() = getSysType(c.g, x.info, tyBool)
 
   case c.kind
   of attachedSink:
@@ -765,7 +765,7 @@ proc atomicRefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
     if isCyclic:
       if isFinal(elemType):
         let typInfo = genBuiltin(c, mGetTypeInfoV2, "getTypeInfoV2", newNodeIT(nkType, x.info, elemType))
-        typInfo.typ = getSysType(c.g, c.info, tyPointer)
+        typInfo.typ() = getSysType(c.g, c.info, tyPointer)
         body.add callCodegenProc(c.g, "nimTraceRef", c.info, genAddrOf(x, c.idgen), typInfo, y)
       else:
         # If the ref is polymorphic we have to account for this
@@ -786,7 +786,7 @@ proc atomicClosureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   ## Closures are really like refs except they always use a virtual destructor
   ## and we need to do the refcounting only on the ref field which we call 'xenv':
   let xenv = genBuiltin(c, mAccessEnv, "accessEnv", x)
-  xenv.typ = getSysType(c.g, c.info, tyPointer)
+  xenv.typ() = getSysType(c.g, c.info, tyPointer)
 
   let isCyclic = c.g.config.selectedGC == gcOrc
   let tmp =
@@ -802,7 +802,7 @@ proc atomicClosureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
     if isCyclic: "nimDecRefIsLastCyclicDyn"
     else: "nimDecRefIsLast"
   let cond = callCodegenProc(c.g, decRefProc, c.info, tmp)
-  cond.typ = getSysType(c.g, x.info, tyBool)
+  cond.typ() = getSysType(c.g, x.info, tyBool)
 
   case c.kind
   of attachedSink:
@@ -814,7 +814,7 @@ proc atomicClosureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
       body.add newAsgnStmt(x, y)
   of attachedAsgn:
     let yenv = genBuiltin(c, mAccessEnv, "accessEnv", y)
-    yenv.typ = getSysType(c.g, c.info, tyPointer)
+    yenv.typ() = getSysType(c.g, c.info, tyPointer)
     if isCyclic:
       body.add genIf(c, yenv, callCodegenProc(c.g, "nimIncRefCyclic", c.info, yenv, getCycleParam(c)))
       body.add newAsgnStmt(x, y)
@@ -826,7 +826,7 @@ proc atomicClosureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
       body.add newAsgnStmt(x, y)
   of attachedDup:
     let yenv = genBuiltin(c, mAccessEnv, "accessEnv", y)
-    yenv.typ = getSysType(c.g, c.info, tyPointer)
+    yenv.typ() = getSysType(c.g, c.info, tyPointer)
     if isCyclic:
       body.add newAsgnStmt(x, y)
       body.add genIf(c, yenv, callCodegenProc(c.g, "nimIncRefCyclic", c.info, yenv, getCycleParam(c)))
@@ -878,7 +878,7 @@ proc ownedRefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   if isFinal(elemType):
     addDestructorCall(c, elemType, actions, genDeref(x, nkDerefExpr))
     var alignOf = genBuiltin(c, mAlignOf, "alignof", newNodeIT(nkType, c.info, elemType))
-    alignOf.typ = getSysType(c.g, c.info, tyInt)
+    alignOf.typ() = getSysType(c.g, c.info, tyInt)
     actions.add callCodegenProc(c.g, "nimRawDispose", c.info, x, alignOf)
   else:
     addDestructorCall(c, elemType, newNodeI(nkStmtList, c.info), genDeref(x, nkDerefExpr))
@@ -901,14 +901,14 @@ proc closureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
     # a big problem is that we don't know the environment's type here, so we
     # have to go through some indirection; we delegate this to the codegen:
     let call = newNodeI(nkCall, c.info, 2)
-    call.typ = t
+    call.typ() = t
     call[0] = newSymNode(createMagic(c.g, c.idgen, "deepCopy", mDeepCopy))
     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}:
     let xx = genBuiltin(c, mAccessEnv, "accessEnv", x)
-    xx.typ = getSysType(c.g, c.info, tyPointer)
+    xx.typ() = getSysType(c.g, c.info, tyPointer)
     case c.kind
     of attachedSink:
       # we 'nil' y out afterwards so we *need* to take over its reference
@@ -917,13 +917,13 @@ proc closureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
       body.add newAsgnStmt(x, y)
     of attachedAsgn:
       let yy = genBuiltin(c, mAccessEnv, "accessEnv", y)
-      yy.typ = getSysType(c.g, c.info, tyPointer)
+      yy.typ() = getSysType(c.g, c.info, tyPointer)
       body.add genIf(c, yy, callCodegenProc(c.g, "nimIncRef", c.info, yy))
       body.add genIf(c, xx, callCodegenProc(c.g, "nimDecWeakRef", c.info, xx))
       body.add newAsgnStmt(x, y)
     of attachedDup:
       let yy = genBuiltin(c, mAccessEnv, "accessEnv", y)
-      yy.typ = getSysType(c.g, c.info, tyPointer)
+      yy.typ() = getSysType(c.g, c.info, tyPointer)
       body.add newAsgnStmt(x, y)
       body.add genIf(c, yy, callCodegenProc(c.g, "nimIncRef", c.info, yy))
     of attachedDestructor:
@@ -938,7 +938,7 @@ proc closureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
 
 proc ownedClosureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   let xx = genBuiltin(c, mAccessEnv, "accessEnv", x)
-  xx.typ = getSysType(c.g, c.info, tyPointer)
+  xx.typ() = getSysType(c.g, c.info, tyPointer)
   var actions = newNodeI(nkStmtList, c.info)
   #discard addDestructorCall(c, elemType, newNodeI(nkStmtList, c.info), genDeref(xx))
   actions.add callCodegenProc(c.g, "nimDestroyAndDispose", c.info, xx)
@@ -1152,8 +1152,8 @@ proc symPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttachedOp
 proc genTypeFieldCopy(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   let xx = genBuiltin(c, mAccessTypeField, "accessTypeField", x)
   let yy = genBuiltin(c, mAccessTypeField, "accessTypeField", y)
-  xx.typ = getSysType(c.g, c.info, tyPointer)
-  yy.typ = xx.typ
+  xx.typ() = getSysType(c.g, c.info, tyPointer)
+  yy.typ() = xx.typ
   body.add newAsgnStmt(xx, yy)
 
 proc produceSym(g: ModuleGraph; c: PContext; typ: PType; kind: TTypeAttachedOp;
diff --git a/compiler/liftlocals.nim b/compiler/liftlocals.nim
index aaa0707e05..682d20c715 100644
--- a/compiler/liftlocals.nim
+++ b/compiler/liftlocals.nim
@@ -32,12 +32,12 @@ proc interestingVar(s: PSym): bool {.inline.} =
 proc lookupOrAdd(c: var Ctx; s: PSym; info: TLineInfo): PNode =
   let field = addUniqueField(c.objType, s, c.cache, c.idgen)
   var deref = newNodeI(nkHiddenDeref, info)
-  deref.typ = c.objType
+  deref.typ() = c.objType
   deref.add(newSymNode(c.partialParam, info))
   result = newNodeI(nkDotExpr, info)
   result.add(deref)
   result.add(newSymNode(field))
-  result.typ = field.typ
+  result.typ() = field.typ
 
 proc liftLocals(n: PNode; i: int; c: var Ctx) =
   let it = n[i]
diff --git a/compiler/lowerings.nim b/compiler/lowerings.nim
index 2c9c4cb323..a55d2776d8 100644
--- a/compiler/lowerings.nim
+++ b/compiler/lowerings.nim
@@ -174,12 +174,12 @@ proc rawIndirectAccess*(a: PNode; field: PSym; info: TLineInfo): PNode =
   # returns a[].field as a node
   assert field.kind == skField
   var deref = newNodeI(nkHiddenDeref, info)
-  deref.typ = a.typ.skipTypes(abstractInst)[0]
+  deref.typ() = a.typ.skipTypes(abstractInst)[0]
   deref.add a
   result = newNodeI(nkDotExpr, info)
   result.add deref
   result.add newSymNode(field)
-  result.typ = field.typ
+  result.typ() = field.typ
 
 proc rawDirectAccess*(obj, field: PSym): PNode =
   # returns a.field as a node
@@ -187,7 +187,7 @@ proc rawDirectAccess*(obj, field: PSym): PNode =
   result = newNodeI(nkDotExpr, field.info)
   result.add newSymNode(obj)
   result.add newSymNode(field)
-  result.typ = field.typ
+  result.typ() = field.typ
 
 proc lookupInRecord(n: PNode, id: ItemId): PSym =
   result = nil
@@ -250,12 +250,12 @@ proc newDotExpr*(obj, b: PSym): PNode =
   assert field != nil, b.name.s
   result.add newSymNode(obj)
   result.add newSymNode(field)
-  result.typ = field.typ
+  result.typ() = field.typ
 
 proc indirectAccess*(a: PNode, b: ItemId, info: TLineInfo): PNode =
   # returns a[].b as a node
   var deref = newNodeI(nkHiddenDeref, info)
-  deref.typ = a.typ.skipTypes(abstractInst).elementType
+  deref.typ() = a.typ.skipTypes(abstractInst).elementType
   var t = deref.typ.skipTypes(abstractInst)
   var field: PSym
   while true:
@@ -273,12 +273,12 @@ proc indirectAccess*(a: PNode, b: ItemId, info: TLineInfo): PNode =
   result = newNodeI(nkDotExpr, info)
   result.add deref
   result.add newSymNode(field)
-  result.typ = field.typ
+  result.typ() = field.typ
 
 proc indirectAccess*(a: PNode, b: string, info: TLineInfo; cache: IdentCache): PNode =
   # returns a[].b as a node
   var deref = newNodeI(nkHiddenDeref, info)
-  deref.typ = a.typ.skipTypes(abstractInst).elementType
+  deref.typ() = a.typ.skipTypes(abstractInst).elementType
   var t = deref.typ.skipTypes(abstractInst)
   var field: PSym
   let bb = getIdent(cache, b)
@@ -297,7 +297,7 @@ proc indirectAccess*(a: PNode, b: string, info: TLineInfo; cache: IdentCache): P
   result = newNodeI(nkDotExpr, info)
   result.add deref
   result.add newSymNode(field)
-  result.typ = field.typ
+  result.typ() = field.typ
 
 proc getFieldFromObj*(t: PType; v: PSym): PSym =
   assert v.kind != skField
@@ -320,7 +320,7 @@ proc indirectAccess*(a, b: PSym, info: TLineInfo): PNode =
 proc genAddrOf*(n: PNode; idgen: IdGenerator; typeKind = tyPtr): PNode =
   result = newNodeI(nkAddr, n.info, 1)
   result[0] = n
-  result.typ = newType(typeKind, idgen, n.typ.owner)
+  result.typ() = newType(typeKind, idgen, n.typ.owner)
   result.typ.rawAddSon(n.typ)
 
 proc genDeref*(n: PNode; k = nkHiddenDeref): PNode =
@@ -344,18 +344,18 @@ proc callCodegenProc*(g: ModuleGraph; name: string;
     if optionalArgs != nil:
       for i in 1..<optionalArgs.len-2:
         result.add optionalArgs[i]
-    result.typ = sym.typ.returnType
+    result.typ() = sym.typ.returnType
 
 proc newIntLit*(g: ModuleGraph; info: TLineInfo; value: BiggestInt): PNode =
   result = nkIntLit.newIntNode(value)
-  result.typ = getSysType(g, info, tyInt)
+  result.typ() = getSysType(g, info, tyInt)
 
 proc genHigh*(g: ModuleGraph; n: PNode): PNode =
   if skipTypes(n.typ, abstractVar).kind == tyArray:
     result = newIntLit(g, n.info, toInt64(lastOrd(g.config, skipTypes(n.typ, abstractVar))))
   else:
     result = newNodeI(nkCall, n.info, 2)
-    result.typ = getSysType(g, n.info, tyInt)
+    result.typ() = getSysType(g, n.info, tyInt)
     result[0] = newSymNode(getSysMagic(g, n.info, "high", mHigh))
     result[1] = n
 
@@ -364,7 +364,7 @@ proc genLen*(g: ModuleGraph; n: PNode): PNode =
     result = newIntLit(g, n.info, toInt64(lastOrd(g.config, skipTypes(n.typ, abstractVar)) + 1))
   else:
     result = newNodeI(nkCall, n.info, 2)
-    result.typ = getSysType(g, n.info, tyInt)
+    result.typ() = getSysType(g, n.info, tyInt)
     result[0] = newSymNode(getSysMagic(g, n.info, "len", mLengthSeq))
     result[1] = n
 
diff --git a/compiler/magicsys.nim b/compiler/magicsys.nim
index 1ec6b9a693..47a71d56cd 100644
--- a/compiler/magicsys.nim
+++ b/compiler/magicsys.nim
@@ -166,4 +166,4 @@ proc makeAddr*(n: PNode; idgen: IdGenerator): PNode =
     result = n
   else:
     result = newTree(nkHiddenAddr, n)
-    result.typ = makePtrType(n.typ, idgen)
+    result.typ() = makePtrType(n.typ, idgen)
diff --git a/compiler/modules.nim b/compiler/modules.nim
index 6e2af8bcc7..7f56119ccc 100644
--- a/compiler/modules.nim
+++ b/compiler/modules.nim
@@ -25,7 +25,7 @@ template getModuleIdent(graph: ModuleGraph, filename: AbsoluteFile): PIdent =
 
 proc partialInitModule*(result: PSym; graph: ModuleGraph; fileIdx: FileIndex; filename: AbsoluteFile) =
   let packSym = getPackage(graph, fileIdx)
-  result.owner = packSym
+  setOwner(result, packSym)
   result.position = int fileIdx
 
 proc newModule*(graph: ModuleGraph; fileIdx: FileIndex): PSym =
diff --git a/compiler/nilcheck.nim b/compiler/nilcheck.nim
index 7e0efc34bb..1fa0e7897c 100644
--- a/compiler/nilcheck.nim
+++ b/compiler/nilcheck.nim
@@ -919,7 +919,7 @@ proc infix(ctx: NilCheckerContext, l: PNode, r: PNode, magic: TMagic): PNode =
     newSymNode(op, r.info),
     l,
     r)
-  result.typ = newType(tyBool, ctx.idgen, nil)
+  result.typ() = newType(tyBool, ctx.idgen, nil)
 
 proc prefixNot(ctx: NilCheckerContext, node: PNode): PNode =
   var cache = newIdentCache()
@@ -929,7 +929,7 @@ proc prefixNot(ctx: NilCheckerContext, node: PNode): PNode =
   result = nkPrefix.newTree(
     newSymNode(op, node.info),
     node)
-  result.typ = newType(tyBool, ctx.idgen, nil)
+  result.typ() = newType(tyBool, ctx.idgen, nil)
 
 proc infixEq(ctx: NilCheckerContext, l: PNode, r: PNode): PNode =
   infix(ctx, l, r, mEqRef)
diff --git a/compiler/nimsets.nim b/compiler/nimsets.nim
index 7edf55278c..c864d63be1 100644
--- a/compiler/nimsets.nim
+++ b/compiler/nimsets.nim
@@ -84,7 +84,7 @@ proc toTreeSet*(conf: ConfigRef; s: TBitSet, settype: PType, info: TLineInfo): P
   elemType = settype[0]
   first = firstOrd(conf, elemType).toInt64
   result = newNodeI(nkCurly, info)
-  result.typ = settype
+  result.typ() = settype
   result.info = info
   e = 0
   while e < s.len * ElemSize:
@@ -101,7 +101,7 @@ proc toTreeSet*(conf: ConfigRef; s: TBitSet, settype: PType, info: TLineInfo): P
         result.add aa
       else:
         n = newNodeI(nkRange, info)
-        n.typ = elemType
+        n.typ() = elemType
         n.add aa
         let bb = newIntTypeNode(b + first, elemType)
         bb.info = info
diff --git a/compiler/pragmas.nim b/compiler/pragmas.nim
index 9a298cd90e..c38fa2e62a 100644
--- a/compiler/pragmas.nim
+++ b/compiler/pragmas.nim
@@ -722,12 +722,12 @@ proc processPragma(c: PContext, n: PNode, i: int) =
 proc pragmaRaisesOrTags(c: PContext, n: PNode) =
   proc processExc(c: PContext, x: PNode) =
     if c.hasUnresolvedArgs(c, x):
-      x.typ = makeTypeFromExpr(c, x)
+      x.typ() = makeTypeFromExpr(c, x)
     else:
       var t = skipTypes(c.semTypeNode(c, x, nil), skipPtrs)
       if t.kind notin {tyObject, tyOr}:
         localError(c.config, x.info, errGenerated, "invalid type for raises/tags list")
-      x.typ = t
+      x.typ() = t
 
   if n.kind in nkPragmaCallKinds and n.len == 2:
     let it = n[1]
diff --git a/compiler/renderer.nim b/compiler/renderer.nim
index cc07c0c2d5..a598a0ae5e 100644
--- a/compiler/renderer.nim
+++ b/compiler/renderer.nim
@@ -1311,10 +1311,11 @@ proc gsub(g: var TSrcGen, n: PNode, c: TContext, fromStmtList = false) =
       put(g, tkCustomLit, n[0].strVal)
       gsub(g, n, 1)
     else:
-      gsub(g, n, 0)
+      for i in 0..<n.len-1:
+        gsub(g, n, i)
       put(g, tkDot, ".")
-      assert n.len == 2, $n.len
-      accentedName(g, n[1])
+      if n.len > 1:
+        accentedName(g, n[^1])
   of nkBind:
     putWithSpace(g, tkBind, "bind")
     gsub(g, n, 0)
diff --git a/compiler/sem.nim b/compiler/sem.nim
index 699bcbb948..2ff4d758d2 100644
--- a/compiler/sem.nim
+++ b/compiler/sem.nim
@@ -102,7 +102,7 @@ proc fitNode(c: PContext, formal: PType, arg: PNode; info: TLineInfo): PNode =
                renderTree(arg, {renderNoComments}))
     # error correction:
     result = copyTree(arg)
-    result.typ = formal
+    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:
     result = nil
@@ -116,7 +116,7 @@ proc fitNode(c: PContext, formal: PType, arg: PNode; info: TLineInfo): PNode =
       typeMismatch(c.config, info, formal, arg.typ, arg)
       # error correction:
       result = copyTree(arg)
-      result.typ = formal
+      result.typ() = formal
     else:
       result = fitNodePostMatch(c, formal, result)
 
@@ -256,7 +256,7 @@ proc newSymG*(kind: TSymKind, n: PNode, c: PContext): PSym =
     # when there is a nested proc inside a template, semtmpl
     # will assign a wrong owner during the first pass over the
     # template; we must fix it here: see #909
-    result.owner = getCurrOwner(c)
+    setOwner(result, getCurrOwner(c))
   else:
     result = newSym(kind, considerQuotedIdent(c, n), c.idgen, getCurrOwner(c), n.info)
     if find(result.name.s, '`') >= 0:
@@ -470,7 +470,7 @@ proc semAfterMacroCall(c: PContext, call, macroResult: PNode,
                    renderTree(result, {renderNoComments}))
         result = newSymNode(errorSym(c, result))
       else:
-        result.typ = makeTypeDesc(c, typ)
+        result.typ() = makeTypeDesc(c, typ)
       #result = symNodeFromType(c, typ, n.info)
     else:
       if s.ast[genericParamsPos] != nil and retType.isMetaType:
@@ -494,7 +494,7 @@ proc semAfterMacroCall(c: PContext, call, macroResult: PNode,
       if retType.kind == tyVoid:
         result = semStmt(c, result, flags)
       else:
-        result = semExpr(c, result, flags, expectedType)
+        result = semExpr(c, result, flags)
         result = fitNode(c, retType, result, result.info)
       #globalError(s.info, errInvalidParamKindX, typeToString(s.typ.returnType))
   dec(c.config.evalTemplateCounter)
@@ -612,7 +612,7 @@ proc defaultFieldsForTuple(c: PContext, recNode: PNode, hasDefault: var bool, ch
                       newNodeIT(nkType, recNode.info, asgnType)
                     )
       asgnExpr.flags.incl nfSkipFieldChecking
-      asgnExpr.typ = recNode.typ
+      asgnExpr.typ() = recNode.typ
       result.add newTree(nkExprColonExpr, recNode, asgnExpr)
   else:
     raiseAssert "unreachable"
@@ -634,7 +634,7 @@ proc defaultFieldsForTheUninitialized(c: PContext, recNode: PNode, checkDefault:
       if checkDefault: # don't add defaults when checking whether a case branch has default fields
         return
       defaultValue = newIntNode(nkIntLit#[c.graph]#, 0)
-      defaultValue.typ = discriminator.typ
+      defaultValue.typ() = discriminator.typ
     selectedBranch = recNode.pickCaseBranchIndex defaultValue
     defaultValue.flags.incl nfSkipFieldChecking
     result.add newTree(nkExprColonExpr, discriminator, defaultValue)
@@ -647,7 +647,7 @@ proc defaultFieldsForTheUninitialized(c: PContext, recNode: PNode, checkDefault:
     elif recType.kind in {tyObject, tyArray, tyTuple}:
       let asgnExpr = defaultNodeField(c, recNode, recNode.typ, checkDefault)
       if asgnExpr != nil:
-        asgnExpr.typ = recNode.typ
+        asgnExpr.typ() = recNode.typ
         asgnExpr.flags.incl nfSkipFieldChecking
         result.add newTree(nkExprColonExpr, recNode, asgnExpr)
   else:
@@ -660,7 +660,7 @@ proc defaultNodeField(c: PContext, a: PNode, aTyp: PType, checkDefault: bool): P
     let child = defaultFieldsForTheUninitialized(c, aTypSkip.n, checkDefault)
     if child.len > 0:
       var asgnExpr = newTree(nkObjConstr, newNodeIT(nkType, a.info, aTyp))
-      asgnExpr.typ = aTyp
+      asgnExpr.typ() = aTyp
       asgnExpr.sons.add child
       result = semExpr(c, asgnExpr)
     else:
@@ -675,7 +675,7 @@ proc defaultNodeField(c: PContext, a: PNode, aTyp: PType, checkDefault: bool): P
               semExprWithType(c, child),
               node
                 ))
-      result.typ = aTyp
+      result.typ() = aTyp
     else:
       result = nil
   of tyTuple:
@@ -684,7 +684,7 @@ proc defaultNodeField(c: PContext, a: PNode, aTyp: PType, checkDefault: bool): P
       let children = defaultFieldsForTuple(c, aTypSkip.n, hasDefault, checkDefault)
       if hasDefault and children.len > 0:
         result = newNodeI(nkTupleConstr, a.info)
-        result.typ = aTyp
+        result.typ() = aTyp
         result.sons.add children
         result = semExpr(c, result)
       else:
diff --git a/compiler/semcall.nim b/compiler/semcall.nim
index 72dcedf99c..a195e9857f 100644
--- a/compiler/semcall.nim
+++ b/compiler/semcall.nim
@@ -636,7 +636,7 @@ proc instGenericConvertersArg*(c: PContext, a: PNode, x: TCandidate) =
     if s.isGenericRoutineStrict:
       let finalCallee = generateInstance(c, s, x.bindings, a.info)
       a[0].sym = finalCallee
-      a[0].typ = finalCallee.typ
+      a[0].typ() = finalCallee.typ
       #a.typ = finalCallee.typ.returnType
 
 proc instGenericConvertersSons*(c: PContext, n: PNode, x: TCandidate) =
@@ -671,13 +671,13 @@ proc inferWithMetatype(c: PContext, formal: PType,
     # This almost exactly replicates the steps taken by the compiler during
     # param matching. It performs an embarrassing amount of back-and-forth
     # type jugling, but it's the price to pay for consistency and correctness
-    result.typ = generateTypeInstance(c, m.bindings, arg.info,
+    result.typ() = generateTypeInstance(c, m.bindings, arg.info,
                                       formal.skipTypes({tyCompositeTypeClass}))
   else:
     typeMismatch(c.config, arg.info, formal, arg.typ, arg)
     # error correction:
     result = copyTree(arg)
-    result.typ = formal
+    result.typ() = formal
 
 proc updateDefaultParams(c: PContext, call: PNode) =
   # In generic procs, the default parameter may be unique for each
@@ -700,7 +700,7 @@ proc updateDefaultParams(c: PContext, call: PNode) =
         pushInfoContext(c.config, call.info, call[0].sym.detailedInfo)
         typeMismatch(c.config, def.info, formal.typ, def.typ, formal.ast)
         popInfoContext(c.config)
-        def.typ = errorType(c)
+        def.typ() = errorType(c)
       call[i] = def
 
 proc getCallLineInfo(n: PNode): TLineInfo =
@@ -784,7 +784,7 @@ proc semResolvedCall(c: PContext, x: var TCandidate,
     result = x.call
     result[0] = newSymNode(finalCallee, getCallLineInfo(result[0]))
     if containsGenericType(result.typ):
-      result.typ = newTypeS(tyError, c)
+      result.typ() = newTypeS(tyError, c)
       incl result.typ.flags, tfCheckedForDestructor
     return
   let gp = finalCallee.ast[genericParamsPos]
@@ -811,7 +811,7 @@ proc semResolvedCall(c: PContext, x: var TCandidate,
           # this node will be used in template substitution,
           # pretend this is an untyped node and let regular sem handle the type
           # to prevent problems where a generic parameter is treated as a value
-          tn.typ = nil
+          tn.typ() = nil
           x.call.add tn
         else:
           internalAssert c.config, false
@@ -821,7 +821,7 @@ proc semResolvedCall(c: PContext, x: var TCandidate,
   markConvertersUsed(c, result)
   result[0] = newSymNode(finalCallee, getCallLineInfo(result[0]))
   if finalCallee.magic notin {mArrGet, mArrPut}:
-    result.typ = finalCallee.typ.returnType
+    result.typ() = finalCallee.typ.returnType
   updateDefaultParams(c, result)
 
 proc canDeref(n: PNode): bool {.inline.} =
@@ -830,7 +830,7 @@ proc canDeref(n: PNode): bool {.inline.} =
 
 proc tryDeref(n: PNode): PNode =
   result = newNodeI(nkHiddenDeref, n.info)
-  result.typ = n.typ.skipTypes(abstractInst)[0]
+  result.typ() = n.typ.skipTypes(abstractInst)[0]
   result.add n
 
 proc semOverloadedCall(c: PContext, n, nOrig: PNode,
@@ -849,7 +849,7 @@ proc semOverloadedCall(c: PContext, n, nOrig: PNode,
   else:
     if c.inGenericContext > 0 and c.matchedConcept == nil:
       result = semGenericStmt(c, n)
-      result.typ = makeTypeFromExpr(c, result.copyTree)
+      result.typ() = makeTypeFromExpr(c, result.copyTree)
     elif efExplain notin flags:
       # repeat the overload resolution,
       # this time enabling all the diagnostic output (this should fail again)
@@ -864,7 +864,7 @@ proc explicitGenericInstError(c: PContext; n: PNode): PNode =
   localError(c.config, getCallLineInfo(n), errCannotInstantiateX % renderTree(n))
   result = n
 
-proc explicitGenericSym(c: PContext, n: PNode, s: PSym): PNode =
+proc explicitGenericSym(c: PContext, n: PNode, s: PSym, errors: var CandidateErrors, doError: bool): PNode =
   if s.kind in {skTemplate, skMacro}:
     internalError c.config, n.info, "cannot get explicitly instantiated symbol of " &
       (if s.kind == skTemplate: "template" else: "macro")
@@ -874,6 +874,11 @@ proc explicitGenericSym(c: PContext, n: PNode, s: PSym): PNode =
   if m.state != csMatch:
     # state is csMatch only if *all* generic params were matched,
     # including implicit parameters
+    if doError:
+      errors.add(CandidateError(
+        sym: s,
+        firstMismatch: m.firstMismatch,
+        diagnostics: m.diagnostics))
     return nil
   var newInst = generateInstance(c, s, m.bindings, n.info)
   newInst.typ.flags.excl tfUnresolved
@@ -893,46 +898,43 @@ proc setGenericParams(c: PContext, n, expectedParams: PNode) =
           nil
       e = semExprWithType(c, n[i], expectedType = constraint)
     if e.typ == nil:
-      n[i].typ = errorType(c)
+      n[i].typ() = errorType(c)
     else:
-      n[i].typ = e.typ.skipTypes({tyTypeDesc})
+      n[i].typ() = e.typ.skipTypes({tyTypeDesc})
 
-proc explicitGenericInstantiation(c: PContext, n: PNode, s: PSym): PNode =
+proc explicitGenericInstantiation(c: PContext, n: PNode, s: PSym, doError: bool): PNode =
   assert n.kind == nkBracketExpr
   setGenericParams(c, n, s.ast[genericParamsPos])
   var s = s
   var a = n[0]
+  var errors: CandidateErrors = @[]
   if a.kind == nkSym:
     # common case; check the only candidate has the right
     # number of generic type parameters:
-    if s.ast[genericParamsPos].safeLen != n.len-1:
-      let expected = s.ast[genericParamsPos].safeLen
-      localError(c.config, getCallLineInfo(n), errGenerated, "cannot instantiate: '" & renderTree(n) &
-         "'; got " & $(n.len-1) & " typeof(s) but expected " & $expected)
-      return n
-    result = explicitGenericSym(c, n, s)
-    if result == nil: result = explicitGenericInstError(c, n)
+    result = explicitGenericSym(c, n, s, errors, doError)
+    if doError and result == nil:
+      notFoundError(c, n, errors)
   elif a.kind in {nkClosedSymChoice, nkOpenSymChoice}:
     # choose the generic proc with the proper number of type parameters.
-    # XXX I think this could be improved by reusing sigmatch.paramTypesMatch.
-    # It's good enough for now.
     result = newNodeI(a.kind, getCallLineInfo(n))
     for i in 0..<a.len:
       var candidate = a[i].sym
       if candidate.kind in {skProc, skMethod, skConverter,
                             skFunc, skIterator}:
-        # it suffices that the candidate has the proper number of generic
-        # type parameters:
-        if candidate.ast[genericParamsPos].safeLen == n.len-1:
-          let x = explicitGenericSym(c, n, candidate)
-          if x != nil: result.add(x)
+        let x = explicitGenericSym(c, n, candidate, errors, doError)
+        if x != nil: result.add(x)
     # get rid of nkClosedSymChoice if not ambiguous:
-    if result.len == 1 and a.kind == nkClosedSymChoice:
-      result = result[0]
-    elif result.len == 0: result = explicitGenericInstError(c, n)
-    # candidateCount != 1: return explicitGenericInstError(c, n)
+    if result.len == 0:
+      result = nil
+      if doError:
+        notFoundError(c, n, errors)
   else:
-    result = explicitGenericInstError(c, n)
+    # probably unreachable: we are trying to instantiate `a` which is not
+    # a sym/symchoice
+    if doError:
+      result = explicitGenericInstError(c, n)
+    else:
+      result = nil
 
 proc searchForBorrowProc(c: PContext, startScope: PScope, fn: PSym): tuple[s: PSym, state: TBorrowState] =
   # Searches for the fn in the symbol table. If the parameter lists are suitable
diff --git a/compiler/semdata.nim b/compiler/semdata.nim
index 16d3d6f5b8..688cd97009 100644
--- a/compiler/semdata.nim
+++ b/compiler/semdata.nim
@@ -195,29 +195,29 @@ proc getIntLitType*(c: PContext; literal: PNode): PType =
 proc setIntLitType*(c: PContext; result: PNode) =
   let i = result.intVal
   case c.config.target.intSize
-  of 8: result.typ = getIntLitType(c, result)
+  of 8: result.typ() = getIntLitType(c, result)
   of 4:
     if i >= low(int32) and i <= high(int32):
-      result.typ = getIntLitType(c, result)
+      result.typ() = getIntLitType(c, result)
     else:
-      result.typ = getSysType(c.graph, result.info, tyInt64)
+      result.typ() = getSysType(c.graph, result.info, tyInt64)
   of 2:
     if i >= low(int16) and i <= high(int16):
-      result.typ = getIntLitType(c, result)
+      result.typ() = getIntLitType(c, result)
     elif i >= low(int32) and i <= high(int32):
-      result.typ = getSysType(c.graph, result.info, tyInt32)
+      result.typ() = getSysType(c.graph, result.info, tyInt32)
     else:
-      result.typ = getSysType(c.graph, result.info, tyInt64)
+      result.typ() = getSysType(c.graph, result.info, tyInt64)
   of 1:
     # 8 bit CPUs are insane ...
     if i >= low(int8) and i <= high(int8):
-      result.typ = getIntLitType(c, result)
+      result.typ() = getIntLitType(c, result)
     elif i >= low(int16) and i <= high(int16):
-      result.typ = getSysType(c.graph, result.info, tyInt16)
+      result.typ() = getSysType(c.graph, result.info, tyInt16)
     elif i >= low(int32) and i <= high(int32):
-      result.typ = getSysType(c.graph, result.info, tyInt32)
+      result.typ() = getSysType(c.graph, result.info, tyInt32)
     else:
-      result.typ = getSysType(c.graph, result.info, tyInt64)
+      result.typ() = getSysType(c.graph, result.info, tyInt64)
   else:
     internalError(c.config, result.info, "invalid int size")
 
@@ -449,7 +449,7 @@ when false:
 proc makeStaticExpr*(c: PContext, n: PNode): PNode =
   result = newNodeI(nkStaticExpr, n.info)
   result.sons = @[n]
-  result.typ = if n.typ != nil and n.typ.kind == tyStatic: n.typ
+  result.typ() = if n.typ != nil and n.typ.kind == tyStatic: n.typ
                else: newTypeS(tyStatic, c, n.typ)
 
 proc makeAndType*(c: PContext, t1, t2: PType): PType =
@@ -508,7 +508,7 @@ proc errorType*(c: PContext): PType =
 
 proc errorNode*(c: PContext, n: PNode): PNode =
   result = newNodeI(nkEmpty, n.info)
-  result.typ = errorType(c)
+  result.typ() = errorType(c)
 
 # These mimic localError
 template localErrorNode*(c: PContext, n: PNode, info: TLineInfo, msg: TMsgKind, arg: string): PNode =
@@ -529,10 +529,11 @@ template localErrorNode*(c: PContext, n: PNode, arg: string): PNode =
   liMessage(c.config, n2.info, errGenerated, arg, doNothing, instLoc())
   errorNode(c, n2)
 
-proc fillTypeS*(dest: PType, kind: TTypeKind, c: PContext) =
-  dest.kind = kind
-  dest.owner = getCurrOwner(c)
-  dest.size = - 1
+when false:
+  proc fillTypeS*(dest: PType, kind: TTypeKind, c: PContext) =
+    dest.kind = kind
+    dest.owner = getCurrOwner(c)
+    dest.size = - 1
 
 proc makeRangeType*(c: PContext; first, last: BiggestInt;
                     info: TLineInfo; intType: PType = nil): PType =
@@ -563,7 +564,7 @@ proc symFromType*(c: PContext; t: PType, info: TLineInfo): PSym =
 
 proc symNodeFromType*(c: PContext, t: PType, info: TLineInfo): PNode =
   result = newSymNode(symFromType(c, t, info), info)
-  result.typ = makeTypeDesc(c, t)
+  result.typ() = makeTypeDesc(c, t)
 
 proc markIndirect*(c: PContext, s: PSym) {.inline.} =
   if s.kind in {skProc, skFunc, skConverter, skMethod, skIterator}:
diff --git a/compiler/semexprs.nim b/compiler/semexprs.nim
index b87c854aa5..a4f4c5927a 100644
--- a/compiler/semexprs.nim
+++ b/compiler/semexprs.nim
@@ -56,11 +56,11 @@ proc semOperand(c: PContext, n: PNode, flags: TExprFlags = {}): PNode =
   if result.typ != nil:
     if result.typ.kind in {tyVar, tyLent}: result = newDeref(result)
   elif {efWantStmt, efAllowStmt} * flags != {}:
-    result.typ = newTypeS(tyVoid, c)
+    result.typ() = newTypeS(tyVoid, c)
   else:
     localError(c.config, n.info, errExprXHasNoType %
                renderTree(result, {renderNoComments}))
-    result.typ = errorType(c)
+    result.typ() = errorType(c)
 
 proc semExprCheck(c: PContext, n: PNode, flags: TExprFlags, expectedType: PType = nil): PNode =
   rejectEmptyNode(n)
@@ -82,14 +82,14 @@ proc semExprCheck(c: PContext, n: PNode, flags: TExprFlags, expectedType: PType
 proc semExprWithType(c: PContext, n: PNode, flags: TExprFlags = {}, expectedType: PType = nil): PNode =
   result = semExprCheck(c, n, flags-{efTypeAllowed}, expectedType)
   if result.typ == nil and efInTypeof in flags:
-    result.typ = c.voidType
+    result.typ() = c.voidType
   elif result.typ == nil or result.typ == c.enforceVoidContext:
     localError(c.config, n.info, errExprXHasNoType %
                 renderTree(result, {renderNoComments}))
-    result.typ = errorType(c)
+    result.typ() = errorType(c)
   elif result.typ.kind == tyError:
     # associates the type error to the current owner
-    result.typ = errorType(c)
+    result.typ() = errorType(c)
   elif efTypeAllowed in flags and result.typ.kind == tyProc and
       hasUnresolvedParams(result, {}):
     # mirrored with semOperand but only on efTypeAllowed
@@ -101,7 +101,7 @@ proc semExprWithType(c: PContext, n: PNode, flags: TExprFlags = {}, expectedType
       else:
         errProcHasNoConcreteType % n.renderTree
     localError(c.config, n.info, err)
-    result.typ = errorType(c)
+    result.typ() = errorType(c)
   else:
     if result.typ.kind in {tyVar, tyLent}: result = newDeref(result)
 
@@ -110,7 +110,7 @@ proc semExprNoDeref(c: PContext, n: PNode, flags: TExprFlags = {}): PNode =
   if result.typ == nil:
     localError(c.config, n.info, errExprXHasNoType %
                renderTree(result, {renderNoComments}))
-    result.typ = errorType(c)
+    result.typ() = errorType(c)
 
 proc semSymGenericInstantiation(c: PContext, n: PNode, s: PSym): PNode =
   result = symChoice(c, n, s, scClosed)
@@ -194,7 +194,7 @@ proc semOpenSym(c: PContext, n: PNode, flags: TExprFlags, expectedType: PType,
     result = nil
     if not isSym:
       # set symchoice node type back to None
-      n.typ = newTypeS(tyNone, c)
+      n.typ() = newTypeS(tyNone, c)
 
 proc semSymChoice(c: PContext, n: PNode, flags: TExprFlags = {}, expectedType: PType = nil): PNode =
   if n.kind == nkOpenSymChoice:
@@ -216,7 +216,7 @@ proc semSymChoice(c: PContext, n: PNode, flags: TExprFlags = {}, expectedType: P
       err.add "  " & candidate.owner.name.s & "." & candidate.name.s
       err.add ": " & typeToString(candidate.typ) & "\n"
     localError(c.config, n.info, err)
-    n.typ = errorType(c)
+    n.typ() = errorType(c)
     result = n
   if result.kind == nkSym:
     result = semSym(c, result, result.sym, flags)
@@ -227,7 +227,7 @@ proc inlineConst(c: PContext, n: PNode, s: PSym): PNode {.inline.} =
     localError(c.config, n.info, "constant of type '" & typeToString(s.typ) & "' has no value")
     result = newSymNode(s)
   else:
-    result.typ = s.typ
+    result.typ() = s.typ
     result.info = n.info
 
 type
@@ -395,7 +395,7 @@ proc semConv(c: PContext, n: PNode; flags: TExprFlags = {}, expectedType: PType
     var evaluated = semStaticExpr(c, n[1], expectedType)
     if evaluated.kind == nkType or evaluated.typ.kind == tyTypeDesc:
       result = n
-      result.typ = c.makeTypeDesc semStaticType(c, evaluated, nil)
+      result.typ() = c.makeTypeDesc semStaticType(c, evaluated, nil)
       return
     elif targetType.base.kind == tyNone:
       return evaluated
@@ -413,7 +413,7 @@ proc semConv(c: PContext, n: PNode; flags: TExprFlags = {}, expectedType: PType
     if targetType.kind == tyOwned:
       t.flags.incl tfHasOwned
     result = newNodeI(nkType, n.info)
-    result.typ = makeTypeDesc(c, t)
+    result.typ() = makeTypeDesc(c, t)
     return
 
   result.add copyTree(n[0])
@@ -429,10 +429,10 @@ proc semConv(c: PContext, n: PNode; flags: TExprFlags = {}, expectedType: PType
   if targetType.kind != tyGenericParam and targetType.isMetaType:
     let final = inferWithMetatype(c, targetType, op, true)
     result.add final
-    result.typ = final.typ
+    result.typ() = final.typ
     return
 
-  result.typ = targetType
+  result.typ() = targetType
   # XXX op is overwritten later on, this is likely added too early
   # here or needs to be overwritten too then.
   result.add op
@@ -440,7 +440,7 @@ proc semConv(c: PContext, n: PNode; flags: TExprFlags = {}, expectedType: PType
   if targetType.kind == tyGenericParam or
       (op.typ != nil and op.typ.kind == tyFromExpr and c.inGenericContext > 0):
     # expression is compiled early in a generic body
-    result.typ = makeTypeFromExpr(c, copyTree(result))
+    result.typ() = makeTypeFromExpr(c, copyTree(result))
     return result
 
   if not isSymChoice(op):
@@ -490,7 +490,7 @@ proc semCast(c: PContext, n: PNode): PNode =
   if not isCastable(c, targetType, castedExpr.typ, n.info):
     localError(c.config, n.info, "expression cannot be cast to '$1'" % $targetType)
   result = newNodeI(nkCast, n.info)
-  result.typ = targetType
+  result.typ() = targetType
   result.add copyTree(n[0])
   result.add castedExpr
 
@@ -504,18 +504,18 @@ proc semLowHigh(c: PContext, n: PNode, m: TMagic): PNode =
     var typ = skipTypes(n[1].typ, abstractVarRange + {tyTypeDesc, tyUserTypeClassInst})
     case typ.kind
     of tySequence, tyString, tyCstring, tyOpenArray, tyVarargs:
-      n.typ = getSysType(c.graph, n.info, tyInt)
+      n.typ() = getSysType(c.graph, n.info, tyInt)
     of tyArray:
-      n.typ = typ.indexType
+      n.typ() = typ.indexType
       if n.typ.kind == tyRange and emptyRange(n.typ.n[0], n.typ.n[1]): #Invalid range
-        n.typ = getSysType(c.graph, n.info, tyInt)
+        n.typ() = getSysType(c.graph, n.info, tyInt)
     of tyInt..tyInt64, tyChar, tyBool, tyEnum, tyUInt..tyUInt64, tyFloat..tyFloat64:
-      n.typ = n[1].typ.skipTypes({tyTypeDesc})
+      n.typ() = n[1].typ.skipTypes({tyTypeDesc})
     of tyGenericParam:
       # prepare this for resolving in semtypinst:
       # we must use copyTree here in order to avoid creating a cycle
       # that could easily turn into an infinite recursion in semtypinst
-      n.typ = makeTypeFromExpr(c, n.copyTree)
+      n.typ() = makeTypeFromExpr(c, n.copyTree)
     else:
       localError(c.config, n.info, "invalid argument for: " & opToStr[m])
   result = n
@@ -531,7 +531,7 @@ proc fixupStaticType(c: PContext, n: PNode) =
   # apply this measure only in code that is enlightened to work
   # with static types.
   if n.typ.kind != tyStatic:
-    n.typ = newTypeS(tyStatic, c, n.typ)
+    n.typ() = newTypeS(tyStatic, c, n.typ)
     n.typ.n = n # XXX: cycles like the one here look dangerous.
                 # Consider using `n.copyTree`
 
@@ -581,7 +581,7 @@ proc isOpImpl(c: PContext, n: PNode, flags: TExprFlags): PNode =
     # `res = sameType(t1, t2)` would be wrong, e.g. for `int is (int|float)`
 
   result = newIntNode(nkIntLit, ord(res))
-  result.typ = n.typ
+  result.typ() = n.typ
 
 proc semIs(c: PContext, n: PNode, flags: TExprFlags): PNode =
   if n.len != 3 or n[2].kind == nkEmpty:
@@ -590,7 +590,7 @@ proc semIs(c: PContext, n: PNode, flags: TExprFlags): PNode =
 
   let boolType = getSysType(c.graph, n.info, tyBool)
   result = n
-  n.typ = boolType
+  n.typ() = boolType
   var liftLhs = true
 
   n[1] = semExprWithType(c, n[1], {efDetermineType, efWantIterator})
@@ -604,7 +604,7 @@ proc semIs(c: PContext, n: PNode, flags: TExprFlags): PNode =
         n[1] = evaluated
       else:
         result = newIntNode(nkIntLit, 0)
-        result.typ = boolType
+        result.typ() = boolType
         return
     elif t2.kind == tyTypeDesc and
         (t2.base.kind == tyNone or tfExplicit in t2.flags):
@@ -634,7 +634,7 @@ proc semOpAux(c: PContext, n: PNode) =
       let info = a[0].info
       a[0] = newIdentNode(considerQuotedIdent(c, a[0], a), info)
       a[1] = semExprWithType(c, a[1], flags)
-      a.typ = a[1].typ
+      a.typ() = a[1].typ
     else:
       n[i] = semExprWithType(c, a, flags)
 
@@ -707,7 +707,7 @@ 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
+  n.typ() = newType
 
 proc arrayConstrType(c: PContext, n: PNode): PType =
   var typ = newTypeS(tyArray, c)
@@ -729,12 +729,12 @@ proc semArrayConstr(c: PContext, n: PNode, flags: TExprFlags; expectedType: PTyp
   var expectedElementType, expectedIndexType: PType = nil
   var expectedBase: PType = nil
   if constructType:
-    result.typ = newTypeS(tyArray, c)
+    result.typ() = newTypeS(tyArray, c)
     rawAddSon(result.typ, nil)     # index type
     if expectedType != nil:
       expectedBase = expectedType.skipTypes(abstractRange-{tyDistinct})
   else:
-    result.typ = n.typ
+    result.typ() = n.typ
     expectedBase = n.typ.skipTypes(abstractRange) # include tyDistinct this time
   if expectedBase != nil:
     case expectedBase.kind
@@ -1002,7 +1002,7 @@ proc evalAtCompileTime(c: PContext, n: PNode): PNode =
         if n[i].typ.isNil or n[i].typ.kind != tyStatic or
             tfUnresolved notin n[i].typ.flags:
           break maybeLabelAsStatic
-      n.typ = newTypeS(tyStatic, c, n.typ)
+      n.typ() = newTypeS(tyStatic, c, n.typ)
       n.typ.flags.incl tfUnresolved
 
   # optimization pass: not necessary for correctness of the semantic pass
@@ -1091,7 +1091,7 @@ proc semOverloadedCallAnalyseEffects(c: PContext, n: PNode, nOrig: PNode,
         if efWantIterable in flags:
           let typ = newTypeS(tyIterable, c)
           rawAddSon(typ, result.typ)
-          result.typ = typ
+          result.typ() = typ
 
 proc resolveIndirectCall(c: PContext; n, nOrig: PNode;
                          t: PType): TCandidate =
@@ -1178,7 +1178,7 @@ proc semIndirectOp(c: PContext, n: PNode, flags: TExprFlags; expectedType: PType
     elif n0.typ.kind == tyFromExpr and c.inGenericContext > 0:
       # don't make assumptions, entire expression needs to be tyFromExpr
       result = semGenericStmt(c, n)
-      result.typ = makeTypeFromExpr(c, result.copyTree)
+      result.typ() = makeTypeFromExpr(c, result.copyTree)
       return
     else:
       n[0] = n0
@@ -1436,7 +1436,7 @@ proc semSym(c: PContext, n: PNode, sym: PSym, flags: TExprFlags): PNode =
     of tyStatic:
       if typ.n != nil:
         result = typ.n
-        result.typ = typ.base
+        result.typ() = typ.base
       else:
         result = newSymNode(s, n.info)
     else:
@@ -1482,11 +1482,11 @@ proc semSym(c: PContext, n: PNode, sym: PSym, flags: TExprFlags): PNode =
     onUse(n.info, s)
     if s.typ.kind == tyStatic:
       result = newSymNode(s, n.info)
-      result.typ = s.typ
+      result.typ() = s.typ
     elif s.ast != nil:
       result = semExpr(c, s.ast)
     else:
-      n.typ = s.typ
+      n.typ() = s.typ
       return n
   of skType:
     if n.kind != nkDotExpr: # dotExpr is already checked by builtinFieldAccess
@@ -1495,7 +1495,7 @@ proc semSym(c: PContext, n: PNode, sym: PSym, flags: TExprFlags): PNode =
     if s.typ.kind == tyStatic and s.typ.base.kind != tyNone and s.typ.n != nil:
       return s.typ.n
     result = newSymNode(s, n.info)
-    result.typ = makeTypeDesc(c, s.typ)
+    result.typ() = makeTypeDesc(c, s.typ)
   of skField:
     # old code, not sure if it's live code:
     markUsed(c, n.info, s)
@@ -1521,7 +1521,7 @@ proc tryReadingGenericParam(c: PContext, n: PNode, i: PIdent, t: PType): PNode =
     if result == c.graph.emptyNode:
       if c.inGenericContext > 0:
         result = semGenericStmt(c, n)
-        result.typ = makeTypeFromExpr(c, result.copyTree)
+        result.typ() = makeTypeFromExpr(c, result.copyTree)
       else:
         result = nil
   of tyUserTypeClasses:
@@ -1529,7 +1529,7 @@ proc tryReadingGenericParam(c: PContext, n: PNode, i: PIdent, t: PType): PNode =
       result = readTypeParameter(c, t, i, n.info)
     elif c.inGenericContext > 0:
       result = semGenericStmt(c, n)
-      result.typ = makeTypeFromExpr(c, copyTree(result))
+      result.typ() = makeTypeFromExpr(c, copyTree(result))
     else:
       result = nil
   of tyGenericBody, tyCompositeTypeClass:
@@ -1538,12 +1538,12 @@ proc tryReadingGenericParam(c: PContext, n: PNode, i: PIdent, t: PType): PNode =
       if result != nil:
         # generic parameter exists, stop here but delay until instantiation
         result = semGenericStmt(c, n)
-        result.typ = makeTypeFromExpr(c, copyTree(result))
+        result.typ() = makeTypeFromExpr(c, copyTree(result))
     else:
       result = nil
   elif c.inGenericContext > 0 and t.containsUnresolvedType:
     result = semGenericStmt(c, n)
-    result.typ = makeTypeFromExpr(c, copyTree(result))
+    result.typ() = makeTypeFromExpr(c, copyTree(result))
   else:
     result = nil
 
@@ -1561,14 +1561,14 @@ proc tryReadingTypeField(c: PContext, n: PNode, i: PIdent, ty: PType): PNode =
     if f != nil:
       result = newSymNode(f)
       result.info = n.info
-      result.typ = ty
+      result.typ() = ty
       markUsed(c, n.info, f)
       onUse(n.info, f)
   of tyObject, tyTuple:
     if ty.n != nil and ty.n.kind == nkRecList:
       let field = lookupInRecord(ty.n, i)
       if field != nil:
-        n.typ = makeTypeDesc(c, field.typ)
+        n.typ() = makeTypeDesc(c, field.typ)
         result = n
   of tyGenericInst:
     result = tryReadingTypeField(c, n, i, ty.skipModifier)
@@ -1615,7 +1615,7 @@ proc builtinFieldAccess(c: PContext; n: PNode; flags: var TExprFlags): PNode =
       # tyFromExpr, but when this happen in a macro this is not a built-in
       # field access and we leave the compiler to compile a normal call:
       if getCurrOwner(c).kind != skMacro:
-        n.typ = makeTypeFromExpr(c, n.copyTree)
+        n.typ() = makeTypeFromExpr(c, n.copyTree)
         flags.incl efCannotBeDotCall
         return n
       else:
@@ -1655,12 +1655,12 @@ proc builtinFieldAccess(c: PContext; n: PNode; flags: var TExprFlags): PNode =
         n[0] = makeDeref(n[0])
         n[1] = newSymNode(f) # we now have the correct field
         n[1].info = info # preserve the original info
-        n.typ = f.typ
+        n.typ() = f.typ
         if check == nil:
           result = n
         else:
           check[0] = n
-          check.typ = n.typ
+          check.typ() = n.typ
           result = check
   elif ty.kind == tyTuple and ty.n != nil:
     f = getSymFromList(ty.n, i)
@@ -1669,7 +1669,7 @@ proc builtinFieldAccess(c: PContext; n: PNode; flags: var TExprFlags): PNode =
       onUse(n[1].info, f)
       n[0] = makeDeref(n[0])
       n[1] = newSymNode(f)
-      n.typ = f.typ
+      n.typ() = f.typ
       result = n
 
   # we didn't find any field, let's look for a generic param
@@ -1718,33 +1718,21 @@ proc semDeref(c: PContext, n: PNode, flags: TExprFlags): PNode =
   result = n
   var t = skipTypes(n[0].typ, {tyGenericInst, tyVar, tyLent, tyAlias, tySink, tyOwned})
   case t.kind
-  of tyRef, tyPtr: n.typ = t.elementType
+  of tyRef, tyPtr: n.typ() = t.elementType
   of tyMetaTypes, tyFromExpr:
-    n.typ = makeTypeFromExpr(c, n.copyTree)
+    n.typ() = makeTypeFromExpr(c, n.copyTree)
   else: result = nil
   #GlobalError(n[0].info, errCircumNeedsPointer)
 
-proc maybeInstantiateGeneric(c: PContext, n: PNode, s: PSym): PNode =
-  ## Instantiates generic if not lacking implicit generics,
-  ## otherwise returns n.
-  let
-    neededGenParams = s.ast[genericParamsPos].len
-    heldGenParams = n.len - 1
-  var implicitParams = 0
-  for x in s.ast[genericParamsPos]:
-    if tfImplicitTypeParam in x.typ.flags:
-      inc implicitParams
-  if heldGenParams != neededGenParams and implicitParams + heldGenParams == neededGenParams:
-    # This is an implicit + explicit generic procedure without all args passed,
-    # kicking back the sem'd symbol fixes #17212
-    # Uncertain the hackiness of this solution.
-    result = n
-  else:
-    result = explicitGenericInstantiation(c, n, s)
-    if result == n:
-      n[0] = copyTree(result[0])
+proc maybeInstantiateGeneric(c: PContext, n: PNode, s: PSym, doError: bool): PNode =
+  ## Attempts to instantiate generic proc symbol(s) with given parameters.
+  ## If instantiation causes errors; if `doError` is `true`, a type mismatch
+  ## error is given, otherwise `nil` is returned.
+  result = explicitGenericInstantiation(c, n, s, doError)
+  if result == n:
+    n[0] = copyTree(result[0])
 
-proc semSubscript(c: PContext, n: PNode, flags: TExprFlags): PNode =
+proc semSubscript(c: PContext, n: PNode, flags: TExprFlags, afterOverloading = false): PNode =
   ## returns nil if not a built-in subscript operator; also called for the
   ## checking of assignments
   result = nil
@@ -1765,10 +1753,10 @@ proc semSubscript(c: PContext, n: PNode, flags: TExprFlags): PNode =
   if arr.kind == tyStatic:
     if arr.base.kind == tyNone:
       result = n
-      result.typ = semStaticType(c, n[1], nil)
+      result.typ() = semStaticType(c, n[1], nil)
       return
     elif arr.n != nil:
-      return semSubscript(c, arr.n, flags)
+      return semSubscript(c, arr.n, flags, afterOverloading)
     else:
       arr = arr.base
 
@@ -1787,18 +1775,18 @@ proc semSubscript(c: PContext, n: PNode, flags: TExprFlags): PNode =
       if arg != nil:
         n[1] = arg
         result = n
-        result.typ = elemType(arr)
+        result.typ() = elemType(arr)
     # Other types have a bit more of leeway
     elif n[1].typ.skipTypes(abstractRange-{tyDistinct}).kind in
         {tyInt..tyInt64, tyUInt..tyUInt64}:
       result = n
-      result.typ = elemType(arr)
+      result.typ() = elemType(arr)
   of tyTypeDesc:
     # The result so far is a tyTypeDesc bound
     # a tyGenericBody. The line below will substitute
     # it with the instantiated type.
     result = n
-    result.typ = makeTypeDesc(c, semTypeNode(c, n, nil))
+    result.typ() = makeTypeDesc(c, semTypeNode(c, n, nil))
     #result = symNodeFromType(c, semTypeNode(c, n, nil), n.info)
   of tyTuple:
     if n.len != 2: return nil
@@ -1808,7 +1796,7 @@ proc semSubscript(c: PContext, n: PNode, flags: TExprFlags): PNode =
     if skipTypes(n[1].typ, {tyGenericInst, tyRange, tyOrdinal, tyAlias, tySink}).kind in
         {tyInt..tyInt64}:
       let idx = getOrdValue(n[1])
-      if idx >= 0 and idx < arr.len: n.typ = arr[toInt(idx)]
+      if idx >= 0 and idx < arr.len: n.typ() = arr[toInt(idx)]
       else:
         localError(c.config, n.info,
           "invalid index $1 in subscript for tuple of length $2" %
@@ -1825,7 +1813,10 @@ proc semSubscript(c: PContext, n: PNode, flags: TExprFlags): PNode =
       of skProc, skFunc, skMethod, skConverter, skIterator:
         # type parameters: partial generic specialization
         n[0] = semSymGenericInstantiation(c, n[0], s)
-        result = maybeInstantiateGeneric(c, n, s)
+        result = maybeInstantiateGeneric(c, n, s, doError = afterOverloading)
+        if result != nil:
+          # check newly created sym/symchoice
+          result = semExpr(c, result, flags)
       of skMacro, skTemplate:
         if efInCall in flags:
           # We are processing macroOrTmpl[] in macroOrTmpl[](...) call.
@@ -1900,7 +1891,7 @@ proc takeImplicitAddr(c: PContext, n: PNode; isLent: bool): PNode =
       localError(c.config, n.info, errExprHasNoAddress)
   result = newNodeIT(nkHiddenAddr, n.info, if n.typ.kind in {tyVar, tyLent}: n.typ else: makePtrType(c, n.typ))
   if n.typ.kind in {tyVar, tyLent}:
-    n.typ = n.typ.elementType
+    n.typ() = n.typ.elementType
   result.add(n)
 
 proc asgnToResultVar(c: PContext, n, le, ri: PNode) {.inline.} =
@@ -2068,7 +2059,7 @@ proc semAsgn(c: PContext, n: PNode; mode=asgnNormal): PNode =
     let lhs = n[0]
     let rhs = semExprWithType(c, n[1], {efTypeAllowed}, le)
     if lhs.kind == nkSym and lhs.sym.kind == skResult:
-      n.typ = c.enforceVoidContext
+      n.typ() = c.enforceVoidContext
       if c.p.owner.kind != skMacro and resultTypeIsInferrable(lhs.sym.typ):
         var rhsTyp = rhs.typ
         if rhsTyp.kind in tyUserTypeClasses and rhsTyp.isResolvedUserTypeClass:
@@ -2079,7 +2070,7 @@ proc semAsgn(c: PContext, n: PNode; mode=asgnNormal): PNode =
           internalAssert c.config, c.p.resultSym != nil
           # Make sure the type is valid for the result variable
           typeAllowedCheck(c, n.info, rhsTyp, skResult)
-          lhs.typ = rhsTyp
+          lhs.typ() = rhsTyp
           c.p.resultSym.typ = rhsTyp
           c.p.owner.typ.setReturnType rhsTyp
         else:
@@ -2127,7 +2118,7 @@ proc semProcBody(c: PContext, n: PNode; expectedType: PType = nil): PNode =
     if result.kind == nkNilLit:
       # or ImplicitlyDiscardable(result):
       # new semantic: 'result = x' triggers the void context
-      result.typ = nil
+      result.typ() = nil
     elif result.kind == nkStmtListExpr and result.typ.kind == tyNil:
       # to keep backwards compatibility bodies like:
       #   nil
@@ -2230,7 +2221,7 @@ proc semDefined(c: PContext, n: PNode): PNode =
   result = newIntNode(nkIntLit, 0)
   result.intVal = ord isDefined(c.config, considerQuotedIdentOrDot(c, n[1], n).s)
   result.info = n.info
-  result.typ = getSysType(c.graph, n.info, tyBool)
+  result.typ() = getSysType(c.graph, n.info, tyBool)
 
 proc lookUpForDeclared(c: PContext, n: PNode, onlyCurrentScope: bool): PSym =
   case n.kind
@@ -2268,7 +2259,7 @@ proc semDeclared(c: PContext, n: PNode, onlyCurrentScope: bool): PNode =
   result = newIntNode(nkIntLit, 0)
   result.intVal = ord lookUpForDeclared(c, n[1], onlyCurrentScope) != nil
   result.info = n.info
-  result.typ = getSysType(c.graph, n.info, tyBool)
+  result.typ() = getSysType(c.graph, n.info, tyBool)
 
 proc expectMacroOrTemplateCall(c: PContext, n: PNode): PSym =
   ## The argument to the proc should be nkCall(...) or similar
@@ -2341,10 +2332,10 @@ proc semExpandToAst(c: PContext, n: PNode): PNode =
     localError(c.config, n.info, "getAst takes a call, but got " & n.renderTree)
   # Preserve the magic symbol in order to be handled in evals.nim
   internalAssert c.config, n[0].sym.magic == mExpandToAst
-  #n.typ = getSysSym("NimNode").typ # expandedSym.getReturnType
+  #n.typ() = getSysSym("NimNode").typ # expandedSym.getReturnType
   if n.kind == nkStmtList and n.len == 1: result = n[0]
   else: result = n
-  result.typ = sysTypeFromName(c.graph, n.info, "NimNode")
+  result.typ() = sysTypeFromName(c.graph, n.info, "NimNode")
 
 proc semExpandToAst(c: PContext, n: PNode, magicSym: PSym,
                     flags: TExprFlags = {}): PNode =
@@ -2514,7 +2505,7 @@ proc semCompiles(c: PContext, n: PNode, flags: TExprFlags): PNode =
 
   result = newIntNode(nkIntLit, ord(tryExpr(c, n[1], flags) != nil))
   result.info = n.info
-  result.typ = getSysType(c.graph, n.info, tyBool)
+  result.typ() = getSysType(c.graph, n.info, tyBool)
 
 proc semShallowCopy(c: PContext, n: PNode, flags: TExprFlags): PNode =
   if n.len == 3:
@@ -2558,7 +2549,7 @@ proc semSizeof(c: PContext, n: PNode): PNode =
   else:
     n[1] = semExprWithType(c, n[1], {efDetermineType})
     #restoreOldStyleType(n[1])
-  n.typ = getSysType(c.graph, n.info, tyInt)
+  n.typ() = getSysType(c.graph, n.info, tyInt)
   result = foldSizeOf(c.config, n, n)
 
 proc semMagic(c: PContext, n: PNode, s: PSym, flags: TExprFlags; expectedType: PType = nil): PNode =
@@ -2600,7 +2591,7 @@ proc semMagic(c: PContext, n: PNode, s: PSym, flags: TExprFlags; expectedType: P
     markUsed(c, n.info, s)
     checkSonsLen(n, 2, c.config)
     result = newStrNodeT(renderTree(n[1], {renderNoComments}), n, c.graph)
-    result.typ = getSysType(c.graph, n.info, tyString)
+    result.typ() = getSysType(c.graph, n.info, tyString)
   of mParallel:
     markUsed(c, n.info, s)
     if parallel notin c.features:
@@ -2626,9 +2617,9 @@ proc semMagic(c: PContext, n: PNode, s: PSym, flags: TExprFlags; expectedType: P
       let typ = result[^1].typ
       if not typ.isEmptyType:
         if spawnResult(typ, c.inParallelStmt > 0) == srFlowVar:
-          result.typ = createFlowVar(c, typ, n.info)
+          result.typ() = createFlowVar(c, typ, n.info)
         else:
-          result.typ = typ
+          result.typ() = typ
         result.add instantiateCreateFlowVarCall(c, typ, n.info).newSymNode
       else:
         result.add c.graph.emptyNode
@@ -2636,7 +2627,7 @@ proc semMagic(c: PContext, n: PNode, s: PSym, flags: TExprFlags; expectedType: P
     markUsed(c, n.info, s)
     result = setMs(n, s)
     result[1] = semExpr(c, n[1])
-    result.typ = n[1].typ
+    result.typ() = n[1].typ
   of mPlugin:
     markUsed(c, n.info, s)
     # semDirectOp with conditional 'afterCallActions':
@@ -2767,18 +2758,18 @@ proc semWhen(c: PContext, n: PNode, semCheck = true): PNode =
     else: illFormedAst(n, c.config)
   if cannotResolve:
     result = semGenericStmt(c, n)
-    result.typ = makeTypeFromExpr(c, result.copyTree)
+    result.typ() = makeTypeFromExpr(c, result.copyTree)
     return
   if result == nil:
     result = newNodeI(nkEmpty, n.info)
   if whenNimvm:
-    result.typ = typ
+    result.typ() = typ
     if n.len == 1:
       result.add(newTree(nkElse, newNode(nkStmtList)))
 
 proc semSetConstr(c: PContext, n: PNode, expectedType: PType = nil): PNode =
   result = newNodeI(nkCurly, n.info)
-  result.typ = newTypeS(tySet, c)
+  result.typ() = newTypeS(tySet, c)
   result.typ.flags.incl tfIsConstructor
   var expectedElementType: PType = nil
   if expectedType != nil and (
@@ -2804,7 +2795,7 @@ proc semSetConstr(c: PContext, n: PNode, expectedType: PType = nil): PNode =
         if doSetType:
           typ = skipTypes(n[i][1].typ,
                           {tyGenericInst, tyVar, tyLent, tyOrdinal, tyAlias, tySink})
-        n[i].typ = n[i][2].typ # range node needs type too
+        n[i].typ() = n[i][2].typ # range node needs type too
       elif n[i].kind == nkRange:
         # already semchecked
         if doSetType:
@@ -2919,7 +2910,7 @@ proc semTupleFieldsConstr(c: PContext, n: PNode, flags: TExprFlags; expectedType
 
     if n[i][1].typ.kind == tyTypeDesc:
       localError(c.config, n[i][1].info, "typedesc not allowed as tuple field.")
-      n[i][1].typ = errorType(c)
+      n[i][1].typ() = errorType(c)
 
     var f = newSymS(skField, n[i][0], c)
     f.typ = skipIntLit(n[i][1].typ.skipTypes({tySink}), c.idgen)
@@ -2928,7 +2919,7 @@ proc semTupleFieldsConstr(c: PContext, n: PNode, flags: TExprFlags; expectedType
     typ.n.add newSymNode(f)
     n[i][0] = newSymNode(f)
     result.add n[i]
-  result.typ = typ
+  result.typ() = typ
 
 proc semTuplePositionsConstr(c: PContext, n: PNode, flags: TExprFlags; expectedType: PType = nil): PNode =
   result = n                  # we don't modify n, but compute the type:
@@ -2949,7 +2940,7 @@ proc semTuplePositionsConstr(c: PContext, n: PNode, flags: TExprFlags; expectedT
       # `const foo = if true: (0, nil) else: (1, new(int))`
       n[i] = fitNode(c, expectedElemType, n[i], n[i].info)
     addSonSkipIntLit(typ, n[i].typ.skipTypes({tySink}), c.idgen)
-  result.typ = typ
+  result.typ() = typ
 
 include semobjconstr
 
@@ -2965,13 +2956,13 @@ proc semBlock(c: PContext, n: PNode; flags: TExprFlags; expectedType: PType = ni
     if sfGenSym notin labl.flags:
       addDecl(c, labl)
     elif labl.owner == nil:
-      labl.owner = c.p.owner
+      setOwner(labl, c.p.owner)
     n[0] = newSymNode(labl, n[0].info)
     suggestSym(c.graph, n[0].info, labl, c.graph.usageSym)
     styleCheckDef(c, labl)
     onDef(n[0].info, labl)
   n[1] = semExpr(c, n[1], flags, expectedType)
-  n.typ = n[1].typ
+  n.typ() = n[1].typ
   if isEmptyType(n.typ): n.transitionSonsKind(nkBlockStmt)
   else: n.transitionSonsKind(nkBlockExpr)
   closeScope(c)
@@ -3049,7 +3040,7 @@ proc semTupleConstr(c: PContext, n: PNode, flags: TExprFlags; expectedType: PTyp
   if isTupleType: # expressions as ``(int, string)`` are reinterpret as type expressions
     result = n
     var typ = semTypeNode(c, n, nil).skipTypes({tyTypeDesc})
-    result.typ = makeTypeDesc(c, typ)
+    result.typ() = makeTypeDesc(c, typ)
   else:
     result = tupexp
 
@@ -3271,10 +3262,10 @@ proc semExpr(c: PContext, n: PNode, flags: TExprFlags = {}, expectedType: PType
       if expectedType != nil and (
           let expected = expectedType.skipTypes(abstractRange-{tyDistinct});
           expected.kind == typeKind):
-        result.typ = expected
+        result.typ() = expected
         changeType(c, result, expectedType, check=true)
       else:
-        result.typ = getSysType(c.graph, n.info, typeKind)
+        result.typ() = getSysType(c.graph, n.info, typeKind)
 
   result = n
   when defined(nimsuggest):
@@ -3309,7 +3300,7 @@ proc semExpr(c: PContext, n: PNode, flags: TExprFlags = {}, expectedType: PType
         #   localError(c.config, n.info, errInstantiateXExplicitly, s.name.s)
       # "procs literals" are 'owned'
       if optOwnedRefs in c.config.globalOptions:
-        result.typ = makeVarType(c, result.typ, tyOwned)
+        result.typ() = makeVarType(c, result.typ, tyOwned)
     of skEnumField:
       result = enumFieldSymChoice(c, n, s, flags)
     else:
@@ -3338,11 +3329,11 @@ proc semExpr(c: PContext, n: PNode, flags: TExprFlags = {}, expectedType: PType
     discard
   of nkNilLit:
     if result.typ == nil:
-      result.typ = getNilType(c)
+      result.typ() = getNilType(c)
       if expectedType != nil and expectedType.kind notin {tyUntyped, tyTyped}:
         var m = newCandidate(c, result.typ)
         if typeRel(m, expectedType, result.typ) >= isSubtype:
-          result.typ = expectedType
+          result.typ() = expectedType
         # or: result = fitNode(c, expectedType, result, n.info)
   of nkIntLit:
     if result.typ == nil:
@@ -3370,10 +3361,10 @@ proc semExpr(c: PContext, n: PNode, flags: TExprFlags = {}, expectedType: PType
       if expectedType != nil and (
           let expected = expectedType.skipTypes(abstractRange-{tyDistinct});
           expected.kind in {tyFloat..tyFloat128}):
-        result.typ = expected
+        result.typ() = expected
         changeType(c, result, expectedType, check=true)
       else:
-        result.typ = getSysType(c.graph, n.info, tyFloat64)
+        result.typ() = getSysType(c.graph, n.info, tyFloat64)
   of nkFloat32Lit: directLiteral(tyFloat32)
   of nkFloat64Lit: directLiteral(tyFloat64)
   of nkFloat128Lit: directLiteral(tyFloat128)
@@ -3382,9 +3373,9 @@ proc semExpr(c: PContext, n: PNode, flags: TExprFlags = {}, expectedType: PType
       if expectedType != nil and (
           let expected = expectedType.skipTypes(abstractRange-{tyDistinct});
           expected.kind in {tyString, tyCstring}):
-        result.typ = expectedType
+        result.typ() = expectedType
       else:
-        result.typ = getSysType(c.graph, n.info, tyString)
+        result.typ() = getSysType(c.graph, n.info, tyString)
   of nkCharLit: directLiteral(tyChar)
   of nkDotExpr:
     result = semFieldAccess(c, n, flags)
@@ -3399,13 +3390,13 @@ proc semExpr(c: PContext, n: PNode, flags: TExprFlags = {}, expectedType: PType
       let modifier = n.modifierTypeKindOfNode
       if modifier != tyNone:
         var baseType = semExpr(c, n[0]).typ.skipTypes({tyTypeDesc})
-        result.typ = c.makeTypeDesc(newTypeS(modifier, c, baseType))
+        result.typ() = c.makeTypeDesc(newTypeS(modifier, c, baseType))
         return
     var typ = semTypeNode(c, n, nil).skipTypes({tyTypeDesc})
-    result.typ = makeTypeDesc(c, typ)
+    result.typ() = makeTypeDesc(c, typ)
   of nkStmtListType:
     let typ = semTypeNode(c, n, nil)
-    result.typ = makeTypeDesc(c, typ)
+    result.typ() = makeTypeDesc(c, typ)
   of nkCall, nkInfix, nkPrefix, nkPostfix, nkCommand, nkCallStrLit:
     # check if it is an expression macro:
     checkMinSonsLen(n, 1, c.config)
diff --git a/compiler/semfold.nim b/compiler/semfold.nim
index 80144ccc04..eb5db88fc9 100644
--- a/compiler/semfold.nim
+++ b/compiler/semfold.nim
@@ -38,7 +38,7 @@ proc newIntNodeT*(intVal: Int128, n: PNode; idgen: IdGenerator; g: ModuleGraph):
   # original type was 'int', not a distinct int etc.
   if n.typ.kind == tyInt:
     # access cache for the int lit type
-    result.typ = getIntLitTypeG(g, result, idgen)
+    result.typ() = getIntLitTypeG(g, result, idgen)
   result.info = n.info
 
 proc newFloatNodeT*(floatVal: BiggestFloat, n: PNode; g: ModuleGraph): PNode =
@@ -46,12 +46,12 @@ proc newFloatNodeT*(floatVal: BiggestFloat, n: PNode; g: ModuleGraph): PNode =
     result = newFloatNode(nkFloat32Lit, floatVal)
   else:
     result = newFloatNode(nkFloatLit, floatVal)
-  result.typ = n.typ
+  result.typ() = n.typ
   result.info = n.info
 
 proc newStrNodeT*(strVal: string, n: PNode; g: ModuleGraph): PNode =
   result = newStrNode(nkStrLit, strVal)
-  result.typ = n.typ
+  result.typ() = n.typ
   result.info = n.info
 
 proc getConstExpr*(m: PSym, n: PNode; idgen: IdGenerator; g: ModuleGraph): PNode
@@ -302,6 +302,9 @@ proc evalOp(m: TMagic, n, a, b, c: PNode; idgen: IdGenerator; g: ModuleGraph): P
   of mMinusSet:
     result = nimsets.diffSets(g.config, a, b)
     result.info = n.info
+  of mXorSet:
+    result = nimsets.symdiffSets(g.config, a, b)
+    result.info = n.info
   of mConStrStr: result = newStrNodeT(getStrOrChar(a) & getStrOrChar(b), n, g)
   of mInSet: result = newIntNodeT(toInt128(ord(inSet(a, b))), n, idgen, g)
   of mRepr:
@@ -316,7 +319,7 @@ proc evalOp(m: TMagic, n, a, b, c: PNode; idgen: IdGenerator; g: ModuleGraph): P
   of mEnumToStr: result = newStrNodeT(ordinalValToString(a, g), n, g)
   of mArrToSeq:
     result = copyTree(a)
-    result.typ = n.typ
+    result.typ() = n.typ
   of mCompileOption:
     result = newIntNodeT(toInt128(ord(commands.testCompileOption(g.config, a.getStr, n.info))), n, idgen, g)
   of mCompileOptionArg:
@@ -411,7 +414,7 @@ proc foldConv(n, a: PNode; idgen: IdGenerator; g: ModuleGraph; check = false): P
       result = newIntNodeT(toInt128(a.getOrdValue != 0), n, idgen, g)
     of tyBool, tyEnum: # xxx shouldn't we disallow `tyEnum`?
       result = a
-      result.typ = n.typ
+      result.typ() = n.typ
     else:
       raiseAssert $srcTyp.kind
   of tyInt..tyInt64, tyUInt..tyUInt64:
@@ -428,7 +431,7 @@ proc foldConv(n, a: PNode; idgen: IdGenerator; g: ModuleGraph; check = false): P
         result = newIntNodeT(val, n, idgen, g)
     else:
       result = a
-      result.typ = n.typ
+      result.typ() = n.typ
     if check and result.kind in {nkCharLit..nkUInt64Lit} and
           dstTyp.kind notin {tyUInt..tyUInt64}:
       rangeCheck(n, getInt(result), g)
@@ -438,12 +441,12 @@ proc foldConv(n, a: PNode; idgen: IdGenerator; g: ModuleGraph; check = false): P
       result = newFloatNodeT(toFloat64(getOrdValue(a)), n, g)
     else:
       result = a
-      result.typ = n.typ
+      result.typ() = n.typ
   of tyOpenArray, tyVarargs, tyProc, tyPointer:
     result = nil
   else:
     result = a
-    result.typ = n.typ
+    result.typ() = n.typ
 
 proc getArrayConstr(m: PSym, n: PNode; idgen: IdGenerator; g: ModuleGraph): PNode =
   if n.kind == nkBracket:
@@ -514,10 +517,10 @@ proc foldConStrStr(m: PSym, n: PNode; idgen: IdGenerator; g: ModuleGraph): PNode
 proc newSymNodeTypeDesc*(s: PSym; idgen: IdGenerator; info: TLineInfo): PNode =
   result = newSymNode(s, info)
   if s.typ.kind != tyTypeDesc:
-    result.typ = newType(tyTypeDesc, idgen, s.owner)
+    result.typ() = newType(tyTypeDesc, idgen, s.owner)
     result.typ.addSonSkipIntLit(s.typ, idgen)
   else:
-    result.typ = s.typ
+    result.typ() = s.typ
 
 proc foldDefine(m, s: PSym, n: PNode; idgen: IdGenerator; g: ModuleGraph): PNode =
   result = nil
@@ -636,7 +639,7 @@ proc getConstExpr(m: PSym, n: PNode; idgen: IdGenerator; g: ModuleGraph): PNode
       if s.typ.kind == tyStatic:
         if s.typ.n != nil and tfUnresolved notin s.typ.flags:
           result = s.typ.n
-          result.typ = s.typ.base
+          result.typ() = s.typ.base
       elif s.typ.isIntLit:
         result = s.typ.n
       else:
@@ -749,7 +752,7 @@ proc getConstExpr(m: PSym, n: PNode; idgen: IdGenerator; g: ModuleGraph): PNode
     if a == nil: return
     if leValueConv(n[1], a) and leValueConv(a, n[2]):
       result = a              # a <= x and x <= b
-      result.typ = n.typ
+      result.typ() = n.typ
     elif n.typ.kind in {tyUInt..tyUInt64}:
       discard "don't check uints"
     else:
@@ -760,7 +763,7 @@ proc getConstExpr(m: PSym, n: PNode; idgen: IdGenerator; g: ModuleGraph): PNode
     var a = getConstExpr(m, n[0], idgen, g)
     if a == nil: return
     result = a
-    result.typ = n.typ
+    result.typ() = n.typ
   of nkHiddenStdConv, nkHiddenSubConv, nkConv:
     var a = getConstExpr(m, n[1], idgen, g)
     if a == nil: return
@@ -777,7 +780,7 @@ proc getConstExpr(m: PSym, n: PNode; idgen: IdGenerator; g: ModuleGraph): PNode
         not (n.typ.kind == tyProc and a.typ.kind == tyProc):
       # we allow compile-time 'cast' for pointer types:
       result = a
-      result.typ = n.typ
+      result.typ() = n.typ
   of nkBracketExpr: result = foldArrayAccess(m, n, idgen, g)
   of nkDotExpr: result = foldFieldAccess(m, n, idgen, g)
   of nkCheckedFieldExpr:
diff --git a/compiler/semgnrc.nim b/compiler/semgnrc.nim
index 74f77a679c..cb51973857 100644
--- a/compiler/semgnrc.nim
+++ b/compiler/semgnrc.nim
@@ -78,10 +78,10 @@ proc semGenericStmtSymbol(c: PContext, n: PNode, s: PSym,
           if result.kind == nkSym:
             result = newOpenSym(result)
           else:
-            result.typ = nil
+            result.typ() = nil
         else:
           result.flags.incl nfDisabledOpenSym
-          result.typ = nil
+          result.typ() = nil
   case s.kind
   of skUnknown:
     # Introduced in this pass! Leave it as an identifier.
@@ -116,7 +116,7 @@ proc semGenericStmtSymbol(c: PContext, n: PNode, s: PSym,
             result = newOpenSym(result)
           else:
             result.flags.incl nfDisabledOpenSym
-            result.typ = nil
+            result.typ() = nil
       else:
         result = n
     else:
@@ -126,7 +126,7 @@ proc semGenericStmtSymbol(c: PContext, n: PNode, s: PSym,
           result = newOpenSym(result)
         else:
           result.flags.incl nfDisabledOpenSym
-          result.typ = nil
+          result.typ() = nil
     onUse(n.info, s)
   of skParam:
     result = n
@@ -145,7 +145,7 @@ proc semGenericStmtSymbol(c: PContext, n: PNode, s: PSym,
           result = newOpenSym(result)
         else:
           result.flags.incl nfDisabledOpenSym
-          result.typ = nil
+          result.typ() = nil
     elif c.inGenericContext > 0 and withinConcept notin flags:
       # don't leave generic param as identifier node in generic type,
       # sigmatch will try to instantiate generic type AST without all params
@@ -157,7 +157,7 @@ proc semGenericStmtSymbol(c: PContext, n: PNode, s: PSym,
           result = newOpenSym(result)
         else:
           result.flags.incl nfDisabledOpenSym
-          result.typ = nil
+          result.typ() = nil
     else:
       result = n
     onUse(n.info, s)
@@ -168,7 +168,7 @@ proc semGenericStmtSymbol(c: PContext, n: PNode, s: PSym,
         result = newOpenSym(result)
       else:
         result.flags.incl nfDisabledOpenSym
-        result.typ = nil
+        result.typ() = nil
     onUse(n.info, s)
 
 proc lookup(c: PContext, n: PNode, flags: TSemGenericFlags,
diff --git a/compiler/seminst.nim b/compiler/seminst.nim
index b9b1a97be1..ab00810f92 100644
--- a/compiler/seminst.nim
+++ b/compiler/seminst.nim
@@ -111,7 +111,7 @@ proc freshGenSyms(c: PContext; n: PNode, owner, orig: PSym, symMap: var SymMappi
     elif s.owner == nil or s.owner.kind == skPackage:
       #echo "copied this ", s.name.s
       x = copySym(s, c.idgen)
-      x.owner = owner
+      setOwner(x, owner)
       idTablePut(symMap, s, x)
       n.sym = x
   else:
@@ -273,7 +273,7 @@ proc instantiateProcType(c: PContext, pt: LayeredIdTable,
     internalAssert c.config, originalParams[i].kind == nkSym
     let oldParam = originalParams[i].sym
     let param = copySym(oldParam, c.idgen)
-    param.owner = prc
+    setOwner(param, prc)
     param.typ = result[i]
 
     # The default value is instantiated and fitted against the final
@@ -302,7 +302,7 @@ proc instantiateProcType(c: PContext, pt: LayeredIdTable,
         # the only way the default value might be inserted).
         param.ast = errorNode(c, def)
         # we know the node is empty, we need the actual type for error message
-        param.ast.typ = def.typ
+        param.ast.typ() = def.typ
       else:
         param.ast = fitNodePostMatch(c, typeToFit, converted)
       param.typ = result[i]
@@ -395,9 +395,9 @@ proc generateInstance(c: PContext, fn: PSym, pt: LayeredIdTable,
     let passc = getLocalPassC(c, producer)
     if passc != "": #pass the local compiler options to the consumer module too
       extccomp.addLocalCompileOption(c.config, passc, toFullPathConsiderDirty(c.config, c.module.info.fileIndex))
-    result.owner = c.module
+    setOwner(result, c.module)
   else:
-    result.owner = fn
+    setOwner(result, fn)
   result.ast = n
   pushOwner(c, result)
 
diff --git a/compiler/semmacrosanity.nim b/compiler/semmacrosanity.nim
index 727f364706..67cc86a14d 100644
--- a/compiler/semmacrosanity.nim
+++ b/compiler/semmacrosanity.nim
@@ -50,8 +50,8 @@ proc annotateType*(n: PNode, t: PType; conf: ConfigRef) =
   case n.kind
   of nkObjConstr:
     let x = t.skipTypes(abstractPtrs)
-    n.typ = t
-    n[0].typ = t
+    n.typ() = t
+    n[0].typ() = t
     for i in 1..<n.len:
       var j = i-1
       let field = x.ithField(j)
@@ -62,12 +62,12 @@ proc annotateType*(n: PNode, t: PType; conf: ConfigRef) =
         annotateType(n[i][1], field.typ, conf)
   of nkPar, nkTupleConstr:
     if x.kind == tyTuple:
-      n.typ = t
+      n.typ() = t
       for i in 0..<n.len:
         if i >= x.kidsLen: globalError conf, n.info, "invalid field at index " & $i
         else: annotateType(n[i], x[i], conf)
     elif x.kind == tyProc and x.callConv == ccClosure:
-      n.typ = t
+      n.typ() = t
     elif x.kind == tyOpenArray: # `opcSlice` transforms slices into tuples
       if n.kind == nkTupleConstr:
         let
@@ -88,39 +88,39 @@ proc annotateType*(n: PNode, t: PType; conf: ConfigRef) =
           globalError(conf, n.info, "Incorrectly generated tuple constr")
         n[] = bracketExpr[]
 
-      n.typ = t
+      n.typ() = t
     else:
       globalError(conf, n.info, "() must have a tuple type")
   of nkBracket:
     if x.kind in {tyArray, tySequence, tyOpenArray}:
-      n.typ = t
+      n.typ() = t
       for m in n: annotateType(m, x.elemType, conf)
     else:
       globalError(conf, n.info, "[] must have some form of array type")
   of nkCurly:
     if x.kind in {tySet}:
-      n.typ = t
+      n.typ() = t
       for m in n: annotateType(m, x.elemType, conf)
     else:
       globalError(conf, n.info, "{} must have the set type")
   of nkFloatLit..nkFloat128Lit:
     if x.kind in {tyFloat..tyFloat128}:
-      n.typ = t
+      n.typ() = t
     else:
       globalError(conf, n.info, "float literal must have some float type")
   of nkCharLit..nkUInt64Lit:
     if x.kind in {tyInt..tyUInt64, tyBool, tyChar, tyEnum}:
-      n.typ = t
+      n.typ() = t
     else:
       globalError(conf, n.info, "integer literal must have some int type")
   of nkStrLit..nkTripleStrLit:
     if x.kind in {tyString, tyCstring}:
-      n.typ = t
+      n.typ() = t
     else:
       globalError(conf, n.info, "string literal must be of some string type")
   of nkNilLit:
     if x.kind in NilableTypes+{tyString, tySequence}:
-      n.typ = t
+      n.typ() = t
     else:
       globalError(conf, n.info, "nil literal must be of some pointer type")
   else: discard
diff --git a/compiler/semmagic.nim b/compiler/semmagic.nim
index a12e933e79..3c4b30f1d3 100644
--- a/compiler/semmagic.nim
+++ b/compiler/semmagic.nim
@@ -18,7 +18,7 @@ proc addDefaultFieldForNew(c: PContext, n: PNode): PNode =
   let typ = result[1].typ # new(x)
   if typ.skipTypes({tyGenericInst, tyAlias, tySink}).kind == tyRef and typ.skipTypes({tyGenericInst, tyAlias, tySink})[0].kind == tyObject:
     var asgnExpr = newTree(nkObjConstr, newNodeIT(nkType, result[1].info, typ))
-    asgnExpr.typ = typ
+    asgnExpr.typ() = typ
     var t = typ.skipTypes({tyGenericInst, tyAlias, tySink})[0]
     while true:
       asgnExpr.sons.add defaultFieldsForTheUninitialized(c, t.n, false)
@@ -38,7 +38,7 @@ proc semAddr(c: PContext; n: PNode): PNode =
   if isAssignable(c, x) notin {arLValue, arLocalLValue, arAddressableConst, arLentValue}:
     localError(c.config, n.info, errExprHasNoAddress)
   result.add x
-  result.typ = makePtrType(c, x.typ)
+  result.typ() = makePtrType(c, x.typ)
 
 proc semTypeOf(c: PContext; n: PNode): PNode =
   var m = BiggestInt 1 # typeOfIter
@@ -55,18 +55,18 @@ proc semTypeOf(c: PContext; n: PNode): PNode =
   result.add typExpr
   if typExpr.typ.kind == tyFromExpr:
     typExpr.typ.flags.incl tfNonConstExpr
-  result.typ = makeTypeDesc(c, typExpr.typ)
+  result.typ() = makeTypeDesc(c, typExpr.typ)
 
 type
   SemAsgnMode = enum asgnNormal, noOverloadedSubscript, noOverloadedAsgn
 
 proc semAsgn(c: PContext, n: PNode; mode=asgnNormal): PNode
-proc semSubscript(c: PContext, n: PNode, flags: TExprFlags): PNode
+proc semSubscript(c: PContext, n: PNode, flags: TExprFlags, afterOverloading = false): PNode
 
 proc semArrGet(c: PContext; n: PNode; flags: TExprFlags): PNode =
   result = newNodeI(nkBracketExpr, n.info)
   for i in 1..<n.len: result.add(n[i])
-  result = semSubscript(c, result, flags)
+  result = semSubscript(c, result, flags, afterOverloading = true)
   if result.isNil:
     let x = copyTree(n)
     x[0] = newIdentNode(getIdent(c.cache, "[]"), n.info)
@@ -76,12 +76,23 @@ proc semArrGet(c: PContext; n: PNode; flags: TExprFlags): PNode =
         if a.typ != nil and a.typ.kind in {tyGenericParam, tyFromExpr}:
           # expression is compiled early in a generic body
           result = semGenericStmt(c, x)
-          result.typ = makeTypeFromExpr(c, copyTree(result))
+          result.typ() = makeTypeFromExpr(c, copyTree(result))
           result.typ.flags.incl tfNonConstExpr
           return
-    bracketNotFoundError(c, x, flags)
-    #localError(c.config, n.info, "could not resolve: " & $n)
-    result = errorNode(c, n)
+    let s = # extract sym from first arg
+      if n.len > 1:
+        if n[1].kind == nkSym: n[1].sym
+        elif n[1].kind in nkSymChoices + {nkOpenSym} and n[1].len != 0:
+          n[1][0].sym
+        else: nil
+      else: nil
+    if s != nil and s.kind in routineKinds:
+      # this is a failed generic instantiation
+      # semSubscript should already error but this is better for cascading errors
+      result = explicitGenericInstError(c, n)
+    else:
+      bracketNotFoundError(c, x, flags)
+      result = errorNode(c, n)
 
 proc semArrPut(c: PContext; n: PNode; flags: TExprFlags): PNode =
   # rewrite `[]=`(a, i, x)  back to ``a[i] = x``.
@@ -189,15 +200,15 @@ proc evalTypeTrait(c: PContext; traitCall: PNode, operand: PType, context: PSym)
       let preferStr = traitCall[2].strVal
       prefer = parseEnum[TPreferedDesc](preferStr)
     result = newStrNode(nkStrLit, operand.typeToString(prefer))
-    result.typ = getSysType(c.graph, traitCall[1].info, tyString)
+    result.typ() = getSysType(c.graph, traitCall[1].info, tyString)
     result.info = traitCall.info
   of "name", "$":
     result = newStrNode(nkStrLit, operand.typeToString(preferTypeName))
-    result.typ = getSysType(c.graph, traitCall[1].info, tyString)
+    result.typ() = getSysType(c.graph, traitCall[1].info, tyString)
     result.info = traitCall.info
   of "arity":
     result = newIntNode(nkIntLit, operand.len - ord(operand.kind==tyProc))
-    result.typ = newType(tyInt, c.idgen, context)
+    result.typ() = newType(tyInt, c.idgen, context)
     result.info = traitCall.info
   of "genericHead":
     var arg = operand
@@ -267,7 +278,7 @@ proc semOrd(c: PContext, n: PNode): PNode =
     discard
   else:
     localError(c.config, n.info, errOrdinalTypeExpected % typeToString(parType, preferDesc))
-    result.typ = errorType(c)
+    result.typ() = errorType(c)
 
 proc semBindSym(c: PContext, n: PNode): PNode =
   result = copyNode(n)
@@ -383,7 +394,7 @@ proc semOf(c: PContext, n: PNode): PNode =
         message(c.config, n.info, hintConditionAlwaysTrue, renderTree(n))
         result = newIntNode(nkIntLit, 1)
         result.info = n.info
-        result.typ = getSysType(c.graph, n.info, tyBool)
+        result.typ() = getSysType(c.graph, n.info, tyBool)
         return result
       elif diff == high(int):
         if commonSuperclass(a, b) == nil:
@@ -392,10 +403,10 @@ proc semOf(c: PContext, n: PNode): PNode =
           message(c.config, n.info, hintConditionAlwaysFalse, renderTree(n))
           result = newIntNode(nkIntLit, 0)
           result.info = n.info
-          result.typ = getSysType(c.graph, n.info, tyBool)
+          result.typ() = getSysType(c.graph, n.info, tyBool)
   else:
     localError(c.config, n.info, "'of' takes 2 arguments")
-  n.typ = getSysType(c.graph, n.info, tyBool)
+  n.typ() = getSysType(c.graph, n.info, tyBool)
   result = n
 
 proc semUnown(c: PContext; n: PNode): PNode =
@@ -430,9 +441,9 @@ proc semUnown(c: PContext; n: PNode): PNode =
       result = t
 
   result = copyTree(n[1])
-  result.typ = unownedType(c, result.typ)
+  result.typ() = unownedType(c, result.typ)
   # little hack for injectdestructors.nim (see bug #11350):
-  #result[0].typ = nil
+  #result[0].typ() = nil
 
 proc turnFinalizerIntoDestructor(c: PContext; orig: PSym; info: TLineInfo): PSym =
   # We need to do 2 things: Replace n.typ which is a 'ref T' by a 'var T' type.
@@ -442,7 +453,7 @@ proc turnFinalizerIntoDestructor(c: PContext; orig: PSym; info: TLineInfo): PSym
   proc transform(c: PContext; n: PNode; old, fresh: PType; oldParam, newParam: PSym): PNode =
     result = shallowCopy(n)
     if sameTypeOrNil(n.typ, old):
-      result.typ = fresh
+      result.typ() = fresh
     if n.kind == nkSym and n.sym == oldParam:
       result.sym = newParam
     for i in 0 ..< safeLen(n):
@@ -453,7 +464,7 @@ proc turnFinalizerIntoDestructor(c: PContext; orig: PSym; info: TLineInfo): PSym
   result = copySym(orig, c.idgen)
   result.info = info
   result.flags.incl sfFromGeneric
-  result.owner = orig
+  setOwner(result, orig)
   let origParamType = orig.typ.firstParamType
   let newParamType = makeVarType(result, origParamType.skipTypes(abstractPtrs), c.idgen)
   let oldParam = orig.typ.n[1].sym
@@ -524,10 +535,10 @@ proc semNewFinalize(c: PContext; n: PNode): PNode =
         discard "already turned this one into a finalizer"
       else:
         if fin.instantiatedFrom != nil and fin.instantiatedFrom != fin.owner: #undo move
-          fin.owner = fin.instantiatedFrom
+          setOwner(fin, fin.instantiatedFrom)
         let wrapperSym = newSym(skProc, getIdent(c.graph.cache, fin.name.s & "FinalizerWrapper"), c.idgen, fin.owner, fin.info)
         let selfSymNode = newSymNode(copySym(fin.ast[paramsPos][1][0].sym, c.idgen))
-        selfSymNode.typ = fin.typ.firstParamType
+        selfSymNode.typ() = fin.typ.firstParamType
         wrapperSym.flags.incl sfUsed
 
         let wrapper = c.semExpr(c, newProcNode(nkProcDef, fin.info, body = newTree(nkCall, newSymNode(fin), selfSymNode),
@@ -539,13 +550,13 @@ proc semNewFinalize(c: PContext; n: PNode): PNode =
           genericParams = fin.ast[genericParamsPos], pragmas = fin.ast[pragmasPos], exceptions = fin.ast[miscPos]), {})
 
         var transFormedSym = turnFinalizerIntoDestructor(c, wrapperSym, wrapper.info)
-        transFormedSym.owner = fin
+        setOwner(transFormedSym, fin)
         if c.config.backend == backendCpp or sfCompileToCpp in c.module.flags:
           let origParamType = transFormedSym.ast[bodyPos][1].typ
           let selfSymbolType = makePtrType(c, origParamType.skipTypes(abstractPtrs))
           let selfPtr = newNodeI(nkHiddenAddr, transFormedSym.ast[bodyPos][1].info)
           selfPtr.add transFormedSym.ast[bodyPos][1]
-          selfPtr.typ = selfSymbolType
+          selfPtr.typ() = selfSymbolType
           transFormedSym.ast[bodyPos][1] = c.semExpr(c, selfPtr)
         # TODO: suppress var destructor warnings; if newFinalizer is not
         # TODO: deprecated, try to implement plain T destructor
@@ -601,7 +612,7 @@ proc magicsAfterOverloadResolution(c: PContext, n: PNode,
   of mTypeTrait: result = semTypeTraits(c, n)
   of mAstToStr:
     result = newStrNodeT(renderTree(n[1], {renderNoComments}), n, c.graph)
-    result.typ = getSysType(c.graph, n.info, tyString)
+    result.typ() = getSysType(c.graph, n.info, tyString)
   of mInstantiationInfo: result = semInstantiationInfo(c, n)
   of mOrd: result = semOrd(c, n)
   of mOf: result = semOf(c, n)
@@ -614,7 +625,7 @@ proc magicsAfterOverloadResolution(c: PContext, n: PNode,
       result = semDynamicBindSym(c, n)
   of mProcCall:
     result = n
-    result.typ = n[1].typ
+    result.typ() = n[1].typ
   of mDotDot:
     result = n
   of mPlugin:
@@ -657,7 +668,7 @@ proc magicsAfterOverloadResolution(c: PContext, n: PNode,
       result[0] = newSymNode(op)
       if op.typ.len == 3:
         let boolLit = newIntLit(c.graph, n.info, 1)
-        boolLit.typ = getSysType(c.graph, n.info, tyBool)
+        boolLit.typ() = getSysType(c.graph, n.info, tyBool)
         result.add boolLit
   of mWasMoved:
     result = n
@@ -699,7 +710,7 @@ proc magicsAfterOverloadResolution(c: PContext, n: PNode,
     result = n
     if result.typ != nil and expectedType != nil and result.typ.kind == tySequence and
         expectedType.kind == tySequence and result.typ.elementType.kind == tyEmpty:
-      result.typ = expectedType # type inference for empty sequence # bug #21377
+      result.typ() = expectedType # type inference for empty sequence # bug #21377
   of mEnsureMove:
     result = n
     if n[1].kind in {nkStmtListExpr, nkBlockExpr,
diff --git a/compiler/semobjconstr.nim b/compiler/semobjconstr.nim
index 048053115e..e90e0bc810 100644
--- a/compiler/semobjconstr.nim
+++ b/compiler/semobjconstr.nim
@@ -188,7 +188,7 @@ proc collectOrAddMissingCaseFields(c: PContext, branchNode: PNode,
           newNodeIT(nkType, constrCtx.initExpr.info, asgnType)
         )
     asgnExpr.flags.incl nfSkipFieldChecking
-    asgnExpr.typ = recTyp
+    asgnExpr.typ() = recTyp
     defaults.add newTree(nkExprColonExpr, newSymNode(sym), asgnExpr)
 
 proc collectBranchFields(c: PContext, n: PNode, discriminatorVal: PNode,
@@ -475,7 +475,7 @@ proc semObjConstr(c: PContext, n: PNode, flags: TExprFlags; expectedType: PType
   if t.kind == tyRef:
     t = skipTypes(t.elementType, {tyGenericInst, tyAlias, tySink, tyOwned})
     if optOwnedRefs in c.config.globalOptions:
-      result.typ = makeVarType(c, result.typ, tyOwned)
+      result.typ() = makeVarType(c, result.typ, tyOwned)
       # 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.flags.incl tfHasOwned
diff --git a/compiler/semparallel.nim b/compiler/semparallel.nim
index 23a8e63626..b0071979bc 100644
--- a/compiler/semparallel.nim
+++ b/compiler/semparallel.nim
@@ -407,9 +407,9 @@ proc transformSlices(g: ModuleGraph; idgen: IdGenerator; n: PNode): PNode =
       result = copyNode(n)
       var typ = newType(tyOpenArray, idgen, result.typ.owner)
       typ.add result.typ.elementType
-      result.typ = typ
+      result.typ() = typ
       let opSlice = newSymNode(createMagic(g, idgen, "slice", mSlice))
-      opSlice.typ = getSysType(g, n.info, tyInt)
+      opSlice.typ() = getSysType(g, n.info, tyInt)
       result.add opSlice
       result.add n[1]
       let slice = n[2].skipStmtList
diff --git a/compiler/sempass2.nim b/compiler/sempass2.nim
index 0a160897f9..76c3d5290b 100644
--- a/compiler/sempass2.nim
+++ b/compiler/sempass2.nim
@@ -193,7 +193,7 @@ proc guardDotAccess(a: PEffects; n: PNode) =
     let dot = newNodeI(nkDotExpr, n.info, 2)
     dot[0] = n[0]
     dot[1] = newSymNode(g)
-    dot.typ = g.typ
+    dot.typ() = g.typ
     for L in a.locked:
       #if a.guards.sameSubexprs(dot, L): return
       if guards.sameTree(dot, L): return
@@ -411,7 +411,7 @@ proc throws(tracked, n, orig: PNode) =
   if n.typ == nil or n.typ.kind != tyError:
     if orig != nil:
       let x = copyTree(orig)
-      x.typ = n.typ
+      x.typ() = n.typ
       tracked.add x
     else:
       tracked.add n
@@ -426,12 +426,12 @@ proc excType(g: ModuleGraph; n: PNode): PType =
 
 proc createRaise(g: ModuleGraph; n: PNode): PNode =
   result = newNode(nkType)
-  result.typ = getEbase(g, n.info)
+  result.typ() = getEbase(g, n.info)
   if not n.isNil: result.info = n.info
 
 proc createTag(g: ModuleGraph; n: PNode): PNode =
   result = newNode(nkType)
-  result.typ = g.sysTypeFromName(n.info, "RootEffect")
+  result.typ() = g.sysTypeFromName(n.info, "RootEffect")
   if not n.isNil: result.info = n.info
 
 proc addRaiseEffect(a: PEffects, e, comesFrom: PNode) =
@@ -1210,7 +1210,7 @@ proc track(tracked: PEffects, n: PNode) =
     if n.sym.typ != nil and tfHasAsgn in n.sym.typ.flags:
       tracked.owner.flags.incl sfInjectDestructors
       # bug #15038: ensure consistency
-      if n.typ == nil or (not hasDestructor(n.typ) and sameType(n.typ, n.sym.typ)): n.typ = n.sym.typ
+      if n.typ == nil or (not hasDestructor(n.typ) and sameType(n.typ, n.sym.typ)): n.typ() = n.sym.typ
   of nkHiddenAddr, nkAddr:
     if n[0].kind == nkSym and isLocalSym(tracked, n[0].sym) and
           n.typ.kind notin {tyVar, tyLent}:
diff --git a/compiler/semstmts.nim b/compiler/semstmts.nim
index 3dad09edfd..8728359e9f 100644
--- a/compiler/semstmts.nim
+++ b/compiler/semstmts.nim
@@ -112,11 +112,11 @@ proc semWhile(c: PContext, n: PNode; flags: TExprFlags): PNode =
   dec(c.p.nestedLoopCounter)
   closeScope(c)
   if n[1].typ == c.enforceVoidContext:
-    result.typ = c.enforceVoidContext
+    result.typ() = c.enforceVoidContext
   elif efInTypeof in flags:
-    result.typ = n[1].typ
+    result.typ() = n[1].typ
   elif implicitlyDiscardable(n[1]):
-    result[1].typ = c.enforceVoidContext
+    result[1].typ() = c.enforceVoidContext
 
 proc semProc(c: PContext, n: PNode): PNode
 
@@ -275,7 +275,7 @@ proc fixNilType(c: PContext; n: PNode) =
   elif n.kind in {nkStmtList, nkStmtListExpr}:
     n.transitionSonsKind(nkStmtList)
     for it in n: fixNilType(c, it)
-  n.typ = nil
+  n.typ() = nil
 
 proc discardCheck(c: PContext, result: PNode, flags: TExprFlags) =
   if c.matchedConcept != nil or efInTypeof in flags: return
@@ -331,14 +331,14 @@ proc semIf(c: PContext, n: PNode; flags: TExprFlags; expectedType: PType = nil):
     for it in n: discardCheck(c, it.lastSon, flags)
     result.transitionSonsKind(nkIfStmt)
     # propagate any enforced VoidContext:
-    if typ == c.enforceVoidContext: result.typ = c.enforceVoidContext
+    if typ == c.enforceVoidContext: result.typ() = c.enforceVoidContext
   else:
     for it in n:
       let j = it.len-1
       if not endsInNoReturn(it[j]):
         it[j] = fitNode(c, typ, it[j], it[j].info)
     result.transitionSonsKind(nkIfExpr)
-    result.typ = typ
+    result.typ() = typ
 
 proc semTry(c: PContext, n: PNode; flags: TExprFlags; expectedType: PType = nil): PNode =
   var check = initIntSet()
@@ -438,7 +438,7 @@ proc semTry(c: PContext, n: PNode; flags: TExprFlags; expectedType: PType = nil)
     discardCheck(c, n[0], flags)
     for i in 1..<n.len: discardCheck(c, n[i].lastSon, flags)
     if typ == c.enforceVoidContext:
-      result.typ = c.enforceVoidContext
+      result.typ() = c.enforceVoidContext
   else:
     if n.lastSon.kind == nkFinally: discardCheck(c, n.lastSon.lastSon, flags)
     if not endsInNoReturn(n[0]):
@@ -448,7 +448,7 @@ proc semTry(c: PContext, n: PNode; flags: TExprFlags; expectedType: PType = nil)
       let j = it.len-1
       if not endsInNoReturn(it[j]):
         it[j] = fitNode(c, typ, it[j], it[j].info)
-    result.typ = typ
+    result.typ() = typ
 
 proc fitRemoveHiddenConv(c: PContext, typ: PType, n: PNode): PNode =
   result = fitNode(c, typ, n, n.info)
@@ -457,7 +457,7 @@ proc fitRemoveHiddenConv(c: PContext, typ: PType, n: PNode): PNode =
     if r1.kind in {nkCharLit..nkUInt64Lit} and typ.skipTypes(abstractRange).kind in {tyFloat..tyFloat128}:
       result = newFloatNode(nkFloatLit, BiggestFloat r1.intVal)
       result.info = n.info
-      result.typ = typ
+      result.typ() = typ
       if not floatRangeCheck(result.floatVal, typ):
         localError(c.config, n.info, errFloatToString % [$result.floatVal, typeToString(typ)])
     elif r1.kind == nkSym and typ.skipTypes(abstractRange).kind == tyCstring:
@@ -605,7 +605,7 @@ proc fillPartialObject(c: PContext; n: PNode; typ: PType) =
       obj.n.add newSymNode(field)
       n[0] = makeDeref x
       n[1] = newSymNode(field)
-      n.typ = field.typ
+      n.typ() = field.typ
     else:
       localError(c.config, n.info, "implicit object field construction " &
         "requires a .partial object, but got " & typeToString(obj))
@@ -908,7 +908,7 @@ proc semVarOrLet(c: PContext, n: PNode, symkind: TSymKind): PNode =
         if sfGenSym notin v.flags:
           if not isDiscardUnderscore(v): addInterfaceDecl(c, v)
         else:
-          if v.owner == nil: v.owner = c.p.owner
+          if v.owner == nil: setOwner(v, c.p.owner)
         when oKeepVariableNames:
           if c.inUnrolledContext > 0: v.flags.incl(sfShadowed)
           else:
@@ -1026,7 +1026,7 @@ proc semConst(c: PContext, n: PNode): PNode =
         when defined(nimsuggest):
           v.hasUserSpecifiedType = hasUserSpecifiedType
         if sfGenSym notin v.flags: addInterfaceDecl(c, v)
-        elif v.owner == nil: v.owner = getCurrOwner(c)
+        elif v.owner == nil: setOwner(v, getCurrOwner(c))
         styleCheckDef(c, v)
         onDef(a[j].info, v)
 
@@ -1097,7 +1097,7 @@ proc semForVars(c: PContext, n: PNode; flags: TExprFlags): PNode =
             v.typ = iter[i]
           n[0][i] = newSymNode(v)
           if sfGenSym notin v.flags and not isDiscardUnderscore(v): addDecl(c, v)
-          elif v.owner == nil: v.owner = getCurrOwner(c)
+          elif v.owner == nil: setOwner(v, getCurrOwner(c))
       else:
         var v = symForVar(c, n[0])
         if getCurrOwner(c).kind == skModule: incl(v.flags, sfGlobal)
@@ -1107,7 +1107,7 @@ proc semForVars(c: PContext, n: PNode; flags: TExprFlags): PNode =
         v.typ = iterBase
         n[0] = newSymNode(v)
         if sfGenSym notin v.flags and not isDiscardUnderscore(v): addDecl(c, v)
-        elif v.owner == nil: v.owner = getCurrOwner(c)
+        elif v.owner == nil: setOwner(v, getCurrOwner(c))
     else:
       localError(c.config, n.info, errWrongNumberOfVariables)
   elif n.len-2 != iterAfterVarLent.len:
@@ -1141,7 +1141,7 @@ proc semForVars(c: PContext, n: PNode; flags: TExprFlags): PNode =
             v.typ = iter[i][j]
           n[i][j] = newSymNode(v)
           if not isDiscardUnderscore(v): addDecl(c, v)
-          elif v.owner == nil: v.owner = getCurrOwner(c)
+          elif v.owner == nil: setOwner(v, getCurrOwner(c))
       else:
         var v = symForVar(c, n[i])
         if getCurrOwner(c).kind == skModule: incl(v.flags, sfGlobal)
@@ -1156,7 +1156,7 @@ proc semForVars(c: PContext, n: PNode; flags: TExprFlags): PNode =
         n[i] = newSymNode(v)
         if sfGenSym notin v.flags:
           if not isDiscardUnderscore(v): addDecl(c, v)
-        elif v.owner == nil: v.owner = getCurrOwner(c)
+        elif v.owner == nil: setOwner(v, getCurrOwner(c))
   inc(c.p.nestedLoopCounter)
   let oldBreakInLoop = c.p.breakInLoop
   c.p.breakInLoop = true
@@ -1291,9 +1291,9 @@ proc semFor(c: PContext, n: PNode; flags: TExprFlags): PNode =
     result = semForVars(c, n, flags)
   # propagate any enforced VoidContext:
   if n[^1].typ == c.enforceVoidContext:
-    result.typ = c.enforceVoidContext
+    result.typ() = c.enforceVoidContext
   elif efInTypeof in flags:
-    result.typ = result.lastSon.typ
+    result.typ() = result.lastSon.typ
   closeScope(c)
 
 proc semCase(c: PContext, n: PNode; flags: TExprFlags; expectedType: PType = nil): PNode =
@@ -1373,14 +1373,14 @@ proc semCase(c: PContext, n: PNode; flags: TExprFlags; expectedType: PType = nil
     for i in 1..<n.len: discardCheck(c, n[i].lastSon, flags)
     # propagate any enforced VoidContext:
     if typ == c.enforceVoidContext:
-      result.typ = c.enforceVoidContext
+      result.typ() = c.enforceVoidContext
   else:
     for i in 1..<n.len:
       var it = n[i]
       let j = it.len-1
       if not endsInNoReturn(it[j]):
         it[j] = fitNode(c, typ, it[j], it[j].info)
-    result.typ = typ
+    result.typ() = typ
 
 proc semRaise(c: PContext, n: PNode): PNode =
   result = n
@@ -1475,7 +1475,7 @@ proc typeDefLeftSidePass(c: PContext, typeSection: PNode, i: int) =
           s = typsym
     # add it here, so that recursive types are possible:
     if sfGenSym notin s.flags: addInterfaceDecl(c, s)
-    elif s.owner == nil: s.owner = getCurrOwner(c)
+    elif s.owner == nil: setOwner(s, getCurrOwner(c))
 
   if name.kind == nkPragmaExpr:
     if name[0].kind == nkPostfix:
@@ -1975,7 +1975,7 @@ proc semInferredLambda(c: PContext, pt: LayeredIdTable, n: PNode): PNode =
   let original = n[namePos].sym
   let s = original #copySym(original, false)
   #incl(s.flags, sfFromGeneric)
-  #s.owner = original
+  #s.owner() = original
 
   n = replaceTypesInBody(c, pt, n, original)
   result = n
@@ -1990,7 +1990,7 @@ proc semInferredLambda(c: PContext, pt: LayeredIdTable, n: PNode): PNode =
                               tyFromExpr}+tyTypeClasses:
       localError(c.config, params[i].info, "cannot infer type of parameter: " &
                  params[i].sym.name.s)
-    #params[i].sym.owner = s
+    #params[i].sym.owner() = s
   openScope(c)
   pushOwner(c, s)
   addParams(c, params, skProc)
@@ -2002,7 +2002,7 @@ proc semInferredLambda(c: PContext, pt: LayeredIdTable, n: PNode): PNode =
   popOwner(c)
   closeScope(c)
   if optOwnedRefs in c.config.globalOptions and result.typ != nil:
-    result.typ = makeVarType(c, result.typ, tyOwned)
+    result.typ() = makeVarType(c, result.typ, tyOwned)
   # alternative variant (not quite working):
   # var prc = arg[0].sym
   # let inferred = c.semGenerateInstance(c, prc, m.bindings, arg.info)
@@ -2362,7 +2362,7 @@ proc semProcAux(c: PContext, n: PNode, kind: TSymKind,
     n[namePos] = newSymNode(s)
   of nkSym:
     s = n[namePos].sym
-    s.owner = c.getCurrOwner
+    setOwner(s, c.getCurrOwner)
   else:
     # Highlighting needs to be done early so the position for
     # name isn't changed (see taccent_highlight). We don't want to check if this is the
@@ -2608,9 +2608,9 @@ proc semProcAux(c: PContext, n: PNode, kind: TSymKind,
     c.patterns.add(s)
   if isAnon:
     n.transitionSonsKind(nkLambda)
-    result.typ = s.typ
+    result.typ() = s.typ
     if optOwnedRefs in c.config.globalOptions:
-      result.typ = makeVarType(c, result.typ, tyOwned)
+      result.typ() = makeVarType(c, result.typ, tyOwned)
   elif isTopLevel(c) and s.kind != skIterator and s.typ.callConv == ccClosure:
     localError(c.config, s.info, "'.closure' calling convention for top level routines is invalid")
 
@@ -2629,7 +2629,7 @@ proc semIterator(c: PContext, n: PNode): PNode =
   # gensym'ed iterator?
   if n[namePos].kind == nkSym:
     # gensym'ed iterators might need to become closure iterators:
-    n[namePos].sym.owner = getCurrOwner(c)
+    setOwner(n[namePos].sym, getCurrOwner(c))
     n[namePos].sym.transitionRoutineSymKind(skIterator)
   result = semProcAux(c, n, skIterator, iteratorPragmas)
   # bug #7093: if after a macro transformation we don't have an
@@ -2650,7 +2650,7 @@ proc semIterator(c: PContext, n: PNode): PNode =
   if n[bodyPos].kind == nkEmpty and s.magic == mNone and c.inConceptDecl == 0:
     localError(c.config, n.info, errImplOfXexpected % s.name.s)
   if optOwnedRefs in c.config.globalOptions and result.typ != nil:
-    result.typ = makeVarType(c, result.typ, tyOwned)
+    result.typ() = makeVarType(c, result.typ, tyOwned)
     result.typ.callConv = ccClosure
 
 proc semProc(c: PContext, n: PNode): PNode =
@@ -2781,7 +2781,7 @@ proc semPragmaBlock(c: PContext, n: PNode; expectedType: PType = nil): PNode =
   n[1] = semExpr(c, n[1], expectedType = expectedType)
   dec c.inUncheckedAssignSection, inUncheckedAssignSection
   result = n
-  result.typ = n[1].typ
+  result.typ() = n[1].typ
   for i in 0..<pragmaList.len:
     case whichPragma(pragmaList[i])
     of wLine: setInfoRecursive(result, pragmaList[i].info)
@@ -2866,14 +2866,14 @@ proc semStmtList(c: PContext, n: PNode, flags: TExprFlags, expectedType: PType =
       else: discard
     if n[i].typ == c.enforceVoidContext: #or usesResult(n[i]):
       voidContext = true
-      n.typ = c.enforceVoidContext
+      n.typ() = c.enforceVoidContext
     if i == last and (n.len == 1 or ({efWantValue, efInTypeof} * flags != {})):
-      n.typ = n[i].typ
+      n.typ() = n[i].typ
       if not isEmptyType(n.typ): n.transitionSonsKind(nkStmtListExpr)
     elif i != last or voidContext:
       discardCheck(c, n[i], flags)
     else:
-      n.typ = n[i].typ
+      n.typ() = n[i].typ
       if not isEmptyType(n.typ): n.transitionSonsKind(nkStmtListExpr)
     var m = n[i]
     while m.kind in {nkStmtListExpr, nkStmtList} and m.len > 0: # from templates
diff --git a/compiler/semtempl.nim b/compiler/semtempl.nim
index f71d7986a5..9954e3c123 100644
--- a/compiler/semtempl.nim
+++ b/compiler/semtempl.nim
@@ -237,10 +237,10 @@ proc semTemplSymbol(c: var TemplCtx, n: PNode, s: PSym; isField, isAmbiguous: bo
         if result.kind == nkSym:
           result = newOpenSym(result)
         else:
-          result.typ = nil
+          result.typ() = nil
       else:
         result.flags.incl nfDisabledOpenSym
-        result.typ = nil
+        result.typ() = nil
   of skGenericParam:
     if isField and sfGenSym in s.flags: result = n
     else:
@@ -250,7 +250,7 @@ proc semTemplSymbol(c: var TemplCtx, n: PNode, s: PSym; isField, isAmbiguous: bo
           result = newOpenSym(result)
         else:
           result.flags.incl nfDisabledOpenSym
-          result.typ = nil
+          result.typ() = nil
   of skParam:
     result = n
   of skType:
@@ -268,10 +268,10 @@ proc semTemplSymbol(c: var TemplCtx, n: PNode, s: PSym; isField, isAmbiguous: bo
           if result.kind == nkSym:
             result = newOpenSym(result)
           else:
-            result.typ = nil
+            result.typ() = nil
         else:
           result.flags.incl nfDisabledOpenSym
-          result.typ = nil
+          result.typ() = nil
   else:
     if isField and sfGenSym in s.flags: result = n
     else:
@@ -281,7 +281,7 @@ proc semTemplSymbol(c: var TemplCtx, n: PNode, s: PSym; isField, isAmbiguous: bo
           result = newOpenSym(result)
         else:
           result.flags.incl nfDisabledOpenSym
-          result.typ = nil
+          result.typ() = nil
     # Issue #12832
     when defined(nimsuggest):
       suggestSym(c.c.graph, n.info, s, c.c.graph.usageSym, false)
diff --git a/compiler/semtypes.nim b/compiler/semtypes.nim
index 113946fef2..870b515121 100644
--- a/compiler/semtypes.nim
+++ b/compiler/semtypes.nim
@@ -480,7 +480,7 @@ proc firstRange(config: ConfigRef, t: PType): PNode =
     result = newFloatNode(nkFloatLit, firstFloat(t))
   else:
     result = newIntNode(nkIntLit, firstOrd(config, t))
-  result.typ = t
+  result.typ() = t
 
 proc semTuple(c: PContext, n: PNode, prev: PType): PType =
   var typ: PType
@@ -1096,7 +1096,7 @@ proc addParamOrResult(c: PContext, param: PSym, kind: TSymKind) =
     if sfGenSym in param.flags:
       # bug #XXX, fix the gensym'ed parameters owner:
       if param.owner == nil:
-        param.owner = getCurrOwner(c)
+        setOwner(param, getCurrOwner(c))
     else: addDecl(c, param)
 
 template shouldHaveMeta(t) =
@@ -1381,7 +1381,7 @@ proc semProcTypeNode(c: PContext, n, genericParams: PNode,
           elif hasUnresolvedArgs(c, def):
             # template default value depends on other parameter
             # don't do any typechecking
-            def.typ = makeTypeFromExpr(c, def.copyTree)
+            def.typ() = makeTypeFromExpr(c, def.copyTree)
             break determineType
           elif typ != nil and typ.kind == tyTyped:
             canBeVoid = true
@@ -1519,7 +1519,7 @@ proc semProcTypeNode(c: PContext, n, genericParams: PNode,
         # XXX This rather hacky way keeps 'tflatmap' compiling:
         if tfHasMeta notin oldFlags:
           result.flags.excl tfHasMeta
-      result.n.typ = r
+      result.n.typ() = r
 
   if isCurrentlyGeneric():
     for n in genericParams:
@@ -1536,8 +1536,8 @@ proc semStmtListType(c: PContext, n: PNode, prev: PType): PType =
     n[i] = semStmt(c, n[i], {})
   if n.len > 0:
     result = semTypeNode(c, n[^1], prev)
-    n.typ = result
-    n[^1].typ = result
+    n.typ() = result
+    n[^1].typ() = result
   else:
     result = nil
 
@@ -1550,15 +1550,15 @@ proc semBlockType(c: PContext, n: PNode, prev: PType): PType =
   if n[0].kind notin {nkEmpty, nkSym}:
     addDecl(c, newSymS(skLabel, n[0], c))
   result = semStmtListType(c, n[1], prev)
-  n[1].typ = result
-  n.typ = result
+  n[1].typ() = result
+  n.typ() = result
   closeScope(c)
   c.p.breakInLoop = oldBreakInLoop
   dec(c.p.nestedBlockCounter)
 
 proc semGenericParamInInvocation(c: PContext, n: PNode): PType =
   result = semTypeNode(c, n, nil)
-  n.typ = makeTypeDesc(c, result)
+  n.typ() = makeTypeDesc(c, result)
 
 proc trySemObjectTypeForInheritedGenericInst(c: PContext, n: PNode, t: PType): bool =
   var
@@ -1970,7 +1970,7 @@ proc semTypeIdent(c: PContext, n: PNode): PSym =
         n.transitionNoneToSym()
         n.sym = result
         n.info = oldInfo
-        n.typ = result.typ
+        n.typ() = result.typ
     else:
       localError(c.config, n.info, "identifier expected")
       result = errorSym(c, n)
@@ -2269,7 +2269,7 @@ proc semTypeNode(c: PContext, n: PNode, prev: PType): PType =
     when false:
       localError(c.config, n.info, "type expected, but got: " & renderTree(n))
       result = newOrPrevType(tyError, prev, c)
-  n.typ = result
+  n.typ() = result
   dec c.inTypeContext
 
 proc setMagicType(conf: ConfigRef; m: PSym, kind: TTypeKind, size: int) =
@@ -2416,7 +2416,7 @@ proc semGenericParamList(c: PContext, n: PNode, father: PType = nil): PNode =
         else:
           # the following line fixes ``TV2*[T:SomeNumber=TR] = array[0..1, T]``
           # from manyloc/named_argument_bug/triengine:
-          def.typ = def.typ.skipTypes({tyTypeDesc})
+          def.typ() = def.typ.skipTypes({tyTypeDesc})
           if not containsGenericType(def.typ):
             def = fitNode(c, typ, def, def.info)
 
diff --git a/compiler/semtypinst.nim b/compiler/semtypinst.nim
index ce5e3e9a65..6a7d140cc8 100644
--- a/compiler/semtypinst.nim
+++ b/compiler/semtypinst.nim
@@ -110,7 +110,7 @@ proc prepareNode*(cl: var TReplTypeVars, n: PNode): PNode =
     return if tfUnresolved in t.flags: prepareNode(cl, t.n)
            else: t.n
   result = copyNode(n)
-  result.typ = t
+  result.typ() = t
   if result.kind == nkSym:
     result.sym =
       if n.typ != nil and n.typ == n.sym.typ:
@@ -264,7 +264,7 @@ proc replaceTypeVarsN(cl: var TReplTypeVars, n: PNode; start=0; expectedType: PT
     if n.typ.kind == tyFromExpr:
       # type of node should not be evaluated as a static value
       n.typ.flags.incl tfNonConstExpr
-    result.typ = replaceTypeVarsT(cl, n.typ)
+    result.typ() = replaceTypeVarsT(cl, n.typ)
     checkMetaInvariants(cl, result.typ)
   case n.kind
   of nkNone..pred(nkSym), succ(nkSym)..nkNilLit:
@@ -358,7 +358,7 @@ proc replaceTypeVarsS(cl: var TReplTypeVars, s: PSym, t: PType): PSym =
   result = copySym(s, cl.c.idgen)
   incl(result.flags, sfFromGeneric)
   #idTablePut(cl.symMap, s, result)
-  result.owner = s.owner
+  setOwner(result, s.owner)
   result.typ = t
   if result.kind != skType:
     result.ast = replaceTypeVarsN(cl, s.ast)
@@ -696,7 +696,7 @@ proc replaceTypeVarsTAux(cl: var TReplTypeVars, t: PType): PType =
     if not cl.allowMetaTypes and result.n != nil and
         result.base.kind != tyNone:
       result.n = cl.c.semConstExpr(cl.c, result.n)
-      result.n.typ = result.base
+      result.n.typ() = result.base
 
   of tyGenericInst, tyUserTypeClassInst:
     bailout()
diff --git a/compiler/sigmatch.nim b/compiler/sigmatch.nim
index 9643f37655..3538ea83cd 100644
--- a/compiler/sigmatch.nim
+++ b/compiler/sigmatch.nim
@@ -200,6 +200,9 @@ proc matchGenericParams*(m: var TCandidate, binding: PNode, callee: PSym) =
     elif tfImplicitTypeParam in paramSym.typ.flags:
       # not a mismatch, but can't create sym
       m.state = csEmpty
+      m.firstMismatch.kind = kMissingGenericParam
+      m.firstMismatch.arg = i + 1
+      m.firstMismatch.formal = paramSym
       return
     else:
       m.state = csNoMatch
@@ -444,11 +447,11 @@ template describeArgImpl(c: PContext, n: PNode, i: int, startIdx = 1; prefer = p
       arg = c.semTryExpr(c, n[i][1])
       if arg == nil:
         arg = n[i][1]
-        arg.typ = newTypeS(tyUntyped, c)
+        arg.typ() = newTypeS(tyUntyped, c)
       else:
         if arg.typ == nil:
-          arg.typ = newTypeS(tyVoid, c)
-        n[i].typ = arg.typ
+          arg.typ() = newTypeS(tyVoid, c)
+        n[i].typ() = arg.typ
         n[i][1] = arg
   else:
     if arg.typ.isNil and arg.kind notin {nkStmtList, nkDo, nkElse,
@@ -457,10 +460,10 @@ template describeArgImpl(c: PContext, n: PNode, i: int, startIdx = 1; prefer = p
       arg = c.semTryExpr(c, n[i])
       if arg == nil:
         arg = n[i]
-        arg.typ = newTypeS(tyUntyped, c)
+        arg.typ() = newTypeS(tyUntyped, c)
       else:
         if arg.typ == nil:
-          arg.typ = newTypeS(tyVoid, c)
+          arg.typ() = newTypeS(tyVoid, c)
         n[i] = arg
   if arg.typ != nil and arg.typ.kind == tyError: return
   result.add argTypeToString(arg, prefer)
@@ -2167,16 +2170,16 @@ proc implicitConv(kind: TNodeKind, f: PType, arg: PNode, m: TCandidate,
   result = newNodeI(kind, arg.info)
   if containsGenericType(f):
     if not m.matchedErrorType:
-      result.typ = getInstantiatedType(c, arg, m, f).skipTypes({tySink})
+      result.typ() = getInstantiatedType(c, arg, m, f).skipTypes({tySink})
     else:
-      result.typ = errorType(c)
+      result.typ() = errorType(c)
   else:
-    result.typ = f.skipTypes({tySink})
+    result.typ() = f.skipTypes({tySink})
   # keep varness
   if arg.typ != nil and arg.typ.kind == tyVar:
-    result.typ = toVar(result.typ, tyVar, c.idgen)
+    result.typ() = toVar(result.typ, tyVar, c.idgen)
   else:
-    result.typ = result.typ.skipTypes({tyVar})
+    result.typ() = result.typ.skipTypes({tyVar})
 
   if result.typ == nil: internalError(c.graph.config, arg.info, "implicitConv")
   result.add c.graph.emptyNode
@@ -2204,13 +2207,13 @@ proc convertLiteral(kind: TNodeKind, c: PContext, m: TCandidate; n: PNode, newTy
         result.add x
       else:
         result.addConsiderNil convertLiteral(kind, c, m, n[i], elemType(newType))
-    result.typ = newType
+    result.typ() = newType
     return
   of nkBracket:
     result = copyNode(n)
     for i in 0..<n.len:
       result.addConsiderNil convertLiteral(kind, c, m, n[i], elemType(newType))
-    result.typ = newType
+    result.typ() = newType
     return
   of nkPar, nkTupleConstr:
     let tup = newType.skipTypes({tyGenericInst, tyAlias, tySink, tyDistinct})
@@ -2234,7 +2237,7 @@ proc convertLiteral(kind: TNodeKind, c: PContext, m: TCandidate; n: PNode, newTy
       else:
         for i in 0..<n.len:
           result.addConsiderNil convertLiteral(kind, c, m, n[i], tup[i])
-      result.typ = newType
+      result.typ() = newType
       return
   of nkCharLit..nkUInt64Lit:
     if n.kind != nkUInt64Lit and not sameTypeOrNil(n.typ, newType) and isOrdinalType(newType):
@@ -2242,14 +2245,14 @@ proc convertLiteral(kind: TNodeKind, c: PContext, m: TCandidate; n: PNode, newTy
       if value < firstOrd(c.config, newType) or value > lastOrd(c.config, newType):
         return nil
       result = copyNode(n)
-      result.typ = newType
+      result.typ() = newType
       return
   of nkFloatLit..nkFloat64Lit:
     if newType.skipTypes(abstractVarRange-{tyTypeDesc}).kind == tyFloat:
       if not floatRangeCheck(n.floatVal, newType):
         return nil
       result = copyNode(n)
-      result.typ = newType
+      result.typ() = newType
       return
   of nkSym:
     if n.sym.kind == skEnumField and not sameTypeOrNil(n.sym.typ, newType) and isOrdinalType(newType):
@@ -2257,7 +2260,7 @@ proc convertLiteral(kind: TNodeKind, c: PContext, m: TCandidate; n: PNode, newTy
       if value < firstOrd(c.config, newType) or value > lastOrd(c.config, newType):
         return nil
       result = copyNode(n)
-      result.typ = newType
+      result.typ() = newType
       return
   else: discard
   return implicitConv(kind, newType, n, m, c)
@@ -2303,7 +2306,7 @@ proc userConvMatch(c: PContext, m: var TCandidate, f, a: PType,
       incl(c.converters[i].flags, sfUsed)
       markOwnerModuleAsUsed(c, c.converters[i])
       var s = newSymNode(c.converters[i])
-      s.typ = c.converters[i].typ
+      s.typ() = c.converters[i].typ
       s.info = arg.info
       result = newNodeIT(nkHiddenCallConv, arg.info, dest)
       result.add s
@@ -2356,7 +2359,7 @@ proc localConvMatch(c: PContext, m: var TCandidate, f, a: PType,
     if result.kind == nkCall: result.transitionSonsKind(nkHiddenCallConv)
     inc(m.convMatches)
     if r == isGeneric:
-      result.typ = getInstantiatedType(c, arg, m, base(f))
+      result.typ() = getInstantiatedType(c, arg, m, base(f))
     m.baseTypeMatch = true
 
 proc incMatches(m: var TCandidate; r: TTypeRelation; convMatch = 1) =
@@ -2412,7 +2415,7 @@ proc paramTypesMatchAux(m: var TCandidate, f, a: PType,
         let typ = newTypeS(tyStatic, c, son = evaluated.typ)
         typ.n = evaluated
         arg = copyTree(arg) # fix #12864
-        arg.typ = typ
+        arg.typ() = typ
         a = typ
       else:
         if m.callee.kind == tyGenericBody:
@@ -2531,7 +2534,7 @@ proc paramTypesMatchAux(m: var TCandidate, f, a: PType,
         # doesn't work: `proc foo[T](): array[T, int] = ...; foo[3]()` (see #23204)
         (arg.typ.isIntLit and not m.isNoCall):
       result = arg.copyTree
-      result.typ = getInstantiatedType(c, arg, m, f).skipTypes({tySink})
+      result.typ() = getInstantiatedType(c, arg, m, f).skipTypes({tySink})
     else:
       result = arg
   of isBothMetaConvertible:
@@ -2587,7 +2590,7 @@ proc paramTypesMatchAux(m: var TCandidate, f, a: PType,
         of isGeneric:
           inc(m.convMatches)
           result = copyTree(arg)
-          result.typ = getInstantiatedType(c, arg, m, base(f))
+          result.typ() = getInstantiatedType(c, arg, m, base(f))
           m.baseTypeMatch = true
         of isFromIntLit:
           inc(m.intConvMatches, 256)
@@ -2613,7 +2616,7 @@ 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)
+    copiedNode.typ() = exactReplica(copiedNode.typ)
     copiedNode.typ.n = arg
     arg = copiedNode
   typeRel(m, f, arg.typ)
@@ -2878,7 +2881,7 @@ proc matchesAux(c: PContext, n, nOrig: PNode, m: var TCandidate, marker: var Int
       m.baseTypeMatch = false
       m.typedescMatched = false
       n[a][1] = prepareOperand(c, formal.typ, n[a][1])
-      n[a].typ = n[a][1].typ
+      n[a].typ() = n[a][1].typ
       arg = paramTypesMatch(m, formal.typ, n[a].typ,
                                 n[a][1], n[a][1])
       m.firstMismatch.kind = kTypeMismatch
@@ -3052,7 +3055,7 @@ proc matches*(c: PContext, n, nOrig: PNode, m: var TCandidate) =
             if m.calleeSym != nil: m.calleeSym.detailedInfo else: "")
           typeMismatch(c.config, formal.ast.info, formal.typ, formal.ast.typ, formal.ast)
           popInfoContext(c.config)
-          formal.ast.typ = errorType(c)
+          formal.ast.typ() = errorType(c)
         if nfDefaultRefsParam in formal.ast.flags:
           m.call.flags.incl nfDefaultRefsParam
         var defaultValue = copyTree(formal.ast)
diff --git a/compiler/sizealignoffsetimpl.nim b/compiler/sizealignoffsetimpl.nim
index 1dd481ec0b..3a3457cb89 100644
--- a/compiler/sizealignoffsetimpl.nim
+++ b/compiler/sizealignoffsetimpl.nim
@@ -477,7 +477,7 @@ template foldSizeOf*(conf: ConfigRef; n: PNode; fallback: PNode): PNode =
   if size >= 0:
     let res = newIntNode(nkIntLit, size)
     res.info = node.info
-    res.typ = node.typ
+    res.typ() = node.typ
     res
   else:
     fallback
@@ -491,7 +491,7 @@ template foldAlignOf*(conf: ConfigRef; n: PNode; fallback: PNode): PNode =
   if align >= 0:
     let res = newIntNode(nkIntLit, align)
     res.info = node.info
-    res.typ = node.typ
+    res.typ() = node.typ
     res
   else:
     fallback
@@ -519,7 +519,7 @@ template foldOffsetOf*(conf: ConfigRef; n: PNode; fallback: PNode): PNode =
   if offset >= 0:
     let tmp = newIntNode(nkIntLit, offset)
     tmp.info = node.info
-    tmp.typ = node.typ
+    tmp.typ() = node.typ
     tmp
   else:
     fallback
diff --git a/compiler/spawn.nim b/compiler/spawn.nim
index 58d5a4928c..99b3b55332 100644
--- a/compiler/spawn.nim
+++ b/compiler/spawn.nim
@@ -16,7 +16,7 @@ from trees import getMagic, getRoot
 proc callProc(a: PNode): PNode =
   result = newNodeI(nkCall, a.info)
   result.add a
-  result.typ = a.typ.returnType
+  result.typ() = a.typ.returnType
 
 # we have 4 cases to consider:
 # - a void proc --> nothing to do
@@ -117,7 +117,7 @@ proc castToVoidPointer(g: ModuleGraph, n: PNode, fvField: PNode): PNode =
     result = newNodeI(nkCast, fvField.info)
     result.add newNodeI(nkEmpty, fvField.info)
     result.add fvField
-    result.typ = ptrType
+    result.typ() = ptrType
 
 proc createWrapperProc(g: ModuleGraph; f: PNode; threadParam, argsParam: PSym;
                        varSection, varInit, call, barrier, fv: PNode;
@@ -200,7 +200,7 @@ proc createCastExpr(argsParam: PSym; objType: PType; idgen: IdGenerator): PNode
   result = newNodeI(nkCast, argsParam.info)
   result.add newNodeI(nkEmpty, argsParam.info)
   result.add newSymNode(argsParam)
-  result.typ = newType(tyPtr, idgen, objType.owner)
+  result.typ() = newType(tyPtr, idgen, objType.owner)
   result.typ.rawAddSon(objType)
 
 template checkMagicProcs(g: ModuleGraph, n: PNode, formal: PNode) =
@@ -266,9 +266,9 @@ proc setupArgsForParallelism(g: ModuleGraph; n: PNode; objType: PType;
     if argType.kind in {tyVarargs, tyOpenArray}:
       # important special case: we always create a zero-copy slice:
       let slice = newNodeI(nkCall, n.info, 4)
-      slice.typ = n.typ
+      slice.typ() = n.typ
       slice[0] = newSymNode(createMagic(g, idgen, "slice", mSlice))
-      slice[0].typ = getSysType(g, n.info, tyInt) # fake type
+      slice[0].typ() = getSysType(g, n.info, tyInt) # fake type
       var fieldB = newSym(skField, tmpName, idgen, objType.owner, n.info, g.config.options)
       fieldB.typ = getSysType(g, n.info, tyInt)
       discard objType.addField(fieldB, g.cache, idgen)
diff --git a/compiler/transf.nim b/compiler/transf.nim
index 8dd24e090c..3db861481a 100644
--- a/compiler/transf.nim
+++ b/compiler/transf.nim
@@ -56,7 +56,6 @@ type
     contSyms, breakSyms: seq[PSym]  # to transform 'continue' and 'break'
     deferDetected, tooEarly: bool
     isIntroducingNewLocalVars: bool  # true if we are in `introducingNewLocalVars` (don't transform yields)
-    inAddr: bool
     flags: TransformFlags
     graph: ModuleGraph
     idgen: IdGenerator
@@ -98,17 +97,14 @@ proc newTemp(c: PTransf, typ: PType, info: TLineInfo): PNode =
   r.typ = typ #skipTypes(typ, {tyGenericInst, tyAlias, tySink})
   incl(r.flags, sfFromGeneric)
   let owner = getCurrOwner(c)
-  if owner.isIterator and not c.tooEarly and not isDefined(c.graph.config, "nimOptIters"):
-    result = freshVarForClosureIter(c.graph, r, c.idgen, owner)
-  else:
-    result = newSymNode(r)
+  result = newSymNode(r)
 
-proc transform(c: PTransf, n: PNode): PNode
+proc transform(c: PTransf, n: PNode, noConstFold = false): PNode
 
-proc transformSons(c: PTransf, n: PNode): PNode =
+proc transformSons(c: PTransf, n: PNode, noConstFold = false): PNode =
   result = newTransNode(n)
   for i in 0..<n.len:
-    result[i] = transform(c, n[i])
+    result[i] = transform(c, n[i], noConstFold)
 
 proc newAsgnStmt(c: PTransf, kind: TNodeKind, le: PNode, ri: PNode; isFirstWrite: bool): PNode =
   result = newTransNode(kind, ri.info, 2)
@@ -177,13 +173,10 @@ proc transformSym(c: PTransf, n: PNode): PNode =
 
 proc freshVar(c: PTransf; v: PSym): PNode =
   let owner = getCurrOwner(c)
-  if owner.isIterator and not c.tooEarly and not isDefined(c.graph.config, "nimOptIters"):
-    result = freshVarForClosureIter(c.graph, v, c.idgen, owner)
-  else:
-    var newVar = copySym(v, c.idgen)
-    incl(newVar.flags, sfFromGeneric)
-    newVar.owner = owner
-    result = newSymNode(newVar)
+  var newVar = copySym(v, c.idgen)
+  incl(newVar.flags, sfFromGeneric)
+  setOwner(newVar, owner)
+  result = newSymNode(newVar)
 
 proc transformVarSection(c: PTransf, v: PNode): PNode =
   result = newTransNode(v)
@@ -363,7 +356,7 @@ proc transformAsgn(c: PTransf, n: PNode): PNode =
     # given tuple type
     newTupleConstr[i] = def[0]
 
-  newTupleConstr.typ = rhs.typ
+  newTupleConstr.typ() = rhs.typ
 
   let asgnNode = newTransNode(nkAsgn, n.info, 2)
   asgnNode[0] = transform(c, n[0])
@@ -481,8 +474,8 @@ proc transformYield(c: PTransf, n: PNode): PNode =
     result.add(introduceNewLocalVars(c, c.transCon.forLoopBody))
     c.isIntroducingNewLocalVars = false
 
-proc transformAddrDeref(c: PTransf, n: PNode, kinds: TNodeKinds): PNode =
-  result = transformSons(c, n)
+proc transformAddrDeref(c: PTransf, n: PNode, kinds: TNodeKinds, isAddr = false): PNode =
+  result = transformSons(c, n, noConstFold = isAddr)
   # inlining of 'var openarray' iterators; bug #19977
   if n.typ.kind != tyOpenArray and (c.graph.config.backend == backendCpp or sfCompileToCpp in c.module.flags): return
   var n = result
@@ -494,9 +487,9 @@ proc transformAddrDeref(c: PTransf, n: PNode, kinds: TNodeKinds): PNode =
       n[0][0] = m[0]
       result = n[0]
       if n.typ.skipTypes(abstractVar).kind != tyOpenArray:
-        result.typ = n.typ
+        result.typ() = n.typ
       elif n.typ.skipTypes(abstractInst).kind in {tyVar}:
-        result.typ = toVar(result.typ, n.typ.skipTypes(abstractInst).kind, c.idgen)
+        result.typ() = toVar(result.typ, n.typ.skipTypes(abstractInst).kind, c.idgen)
   of nkHiddenStdConv, nkHiddenSubConv, nkConv:
     var m = n[0][1]
     if m.kind in kinds:
@@ -504,9 +497,9 @@ proc transformAddrDeref(c: PTransf, n: PNode, kinds: TNodeKinds): PNode =
       n[0][1] = m[0]
       result = n[0]
       if n.typ.skipTypes(abstractVar).kind != tyOpenArray:
-        result.typ = n.typ
+        result.typ() = n.typ
       elif n.typ.skipTypes(abstractInst).kind in {tyVar}:
-        result.typ = toVar(result.typ, n.typ.skipTypes(abstractInst).kind, c.idgen)
+        result.typ() = toVar(result.typ, n.typ.skipTypes(abstractInst).kind, c.idgen)
   else:
     if n[0].kind in kinds and
         not (n[0][0].kind == nkSym and n[0][0].sym.kind == skForVar and
@@ -520,7 +513,7 @@ proc transformAddrDeref(c: PTransf, n: PNode, kinds: TNodeKinds): PNode =
       # addr ( deref ( x )) --> x
       result = n[0][0]
       if n.typ.skipTypes(abstractVar).kind != tyOpenArray:
-        result.typ = n.typ
+        result.typ() = n.typ
 
 proc generateThunk(c: PTransf; prc: PNode, dest: PType): PNode =
   ## Converts 'prc' into '(thunk, nil)' so that it's compatible with
@@ -579,7 +572,7 @@ proc transformConv(c: PTransf, n: PNode): PNode =
     else:
       result = transform(c, n[1])
       #result = transformSons(c, n)
-      result.typ = takeType(n.typ, n[1].typ, c.graph, c.idgen)
+      result.typ() = takeType(n.typ, n[1].typ, c.graph, c.idgen)
       #echo n.info, " came here and produced ", typeToString(result.typ),
       #   " from ", typeToString(n.typ), " and ", typeToString(n[1].typ)
   of tyCstring:
@@ -607,7 +600,7 @@ proc transformConv(c: PTransf, n: PNode): PNode =
         result[0] = transform(c, n[1])
       else:
         result = transform(c, n[1])
-        result.typ = n.typ
+        result.typ() = n.typ
     else:
       result = transformSons(c, n)
   of tyObject:
@@ -620,7 +613,7 @@ proc transformConv(c: PTransf, n: PNode): PNode =
       result[0] = transform(c, n[1])
     else:
       result = transform(c, n[1])
-      result.typ = n.typ
+      result.typ() = n.typ
   of tyGenericParam, tyOrdinal:
     result = transform(c, n[1])
     # happens sometimes for generated assignments, etc.
@@ -840,7 +833,7 @@ proc transformCase(c: PTransf, n: PNode): PNode =
         # as an expr
         let kind = if n.typ != nil: nkIfExpr else: nkIfStmt
         ifs = newTransNode(kind, it.info, 0)
-        ifs.typ = n.typ
+        ifs.typ() = n.typ
       ifs.add(e)
     of nkElse:
       if ifs == nil: result.add(e)
@@ -948,7 +941,7 @@ proc transformExceptBranch(c: PTransf, n: PNode): PNode =
     let convNode = newTransNode(nkHiddenSubConv, n[1].info, 2)
     convNode[0] = newNodeI(nkEmpty, n.info)
     convNode[1] = excCall
-    convNode.typ = excTypeNode.typ.toRef(c.idgen)
+    convNode.typ() = excTypeNode.typ.toRef(c.idgen)
     # -> let exc = ...
     let identDefs = newTransNode(nkIdentDefs, n[1].info, 3)
     identDefs[0] = n[0][2]
@@ -1005,12 +998,12 @@ proc transformDerefBlock(c: PTransf, n: PNode): PNode =
   # We transform (block: x)[] to (block: x[])
   let e0 = n[0]
   result = shallowCopy(e0)
-  result.typ = n.typ
+  result.typ() = n.typ
   for i in 0 ..< e0.len - 1:
     result[i] = e0[i]
   result[e0.len-1] = newTreeIT(nkHiddenDeref, n.info, n.typ, e0[e0.len-1])
 
-proc transform(c: PTransf, n: PNode): PNode =
+proc transform(c: PTransf, n: PNode, noConstFold = false): PNode =
   when false:
     var oldDeferAnchor: PNode
     if n.kind in {nkElifBranch, nkOfBranch, nkExceptBranch, nkElifExpr,
@@ -1077,12 +1070,9 @@ proc transform(c: PTransf, n: PNode): PNode =
   of nkCallKinds:
     result = transformCall(c, n)
   of nkHiddenAddr:
-    result = transformAddrDeref(c, n, {nkHiddenDeref})
+    result = transformAddrDeref(c, n, {nkHiddenDeref}, isAddr = true)
   of nkAddr:
-    let oldInAddr = c.inAddr
-    c.inAddr = true
-    result = transformAddrDeref(c, n, {nkDerefExpr, nkHiddenDeref})
-    c.inAddr = oldInAddr
+    result = transformAddrDeref(c, n, {nkDerefExpr, nkHiddenDeref}, isAddr = true)
   of nkDerefExpr:
     result = transformAddrDeref(c, n, {nkAddr, nkHiddenAddr})
   of nkHiddenDeref:
@@ -1162,7 +1152,7 @@ proc transform(c: PTransf, n: PNode): PNode =
   let exprIsPointerCast = n.kind in {nkCast, nkConv, nkHiddenStdConv} and
                           n.typ != nil and
                           n.typ.kind == tyPointer
-  if not exprIsPointerCast and not c.inAddr:
+  if not exprIsPointerCast and not noConstFold:
     var cnst = getConstExpr(c.module, result, c.idgen, c.graph)
     # we inline constants if they are not complex constants:
     if cnst != nil and not dontInlineConstant(n, cnst):
@@ -1212,7 +1202,7 @@ proc liftDeferAux(n: PNode) =
           tryStmt.add deferPart
           n[i] = tryStmt
           n.sons.setLen(i+1)
-          n.typ = tryStmt.typ
+          n.typ() = tryStmt.typ
           goOn = true
           break
   for i in 0..n.safeLen-1:
diff --git a/compiler/types.nim b/compiler/types.nim
index a441b0ea2b..fef564f586 100644
--- a/compiler/types.nim
+++ b/compiler/types.nim
@@ -1685,7 +1685,7 @@ proc skipHidden*(n: PNode): PNode =
 
 proc skipConvTakeType*(n: PNode): PNode =
   result = n.skipConv
-  result.typ = n.typ
+  result.typ() = n.typ
 
 proc isEmptyContainer*(t: PType): bool =
   case t.kind
@@ -1725,7 +1725,7 @@ proc skipHiddenSubConv*(n: PNode; g: ModuleGraph; idgen: IdGenerator): PNode =
       result = n
     else:
       result = copyTree(result)
-      result.typ = dest
+      result.typ() = dest
   else:
     result = n
 
diff --git a/compiler/vm.nim b/compiler/vm.nim
index 161b025a65..f26d41324f 100644
--- a/compiler/vm.nim
+++ b/compiler/vm.nim
@@ -202,7 +202,7 @@ proc copyValue(src: PNode): PNode =
     return src
   result = newNode(src.kind)
   result.info = src.info
-  result.typ = src.typ
+  result.typ() = src.typ
   result.flags = src.flags * PersistentNodeFlags
   result.comment = src.comment
   when defined(useNodeIds):
@@ -1276,6 +1276,11 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): TFullReg =
       createSet(regs[ra])
       move(regs[ra].node.sons,
            nimsets.diffSets(c.config, regs[rb].node, regs[rc].node).sons)
+    of opcXorSet:
+      decodeBC(rkNode)
+      createSet(regs[ra])
+      move(regs[ra].node.sons,
+           nimsets.symdiffSets(c.config, regs[rb].node, regs[rc].node).sons)
     of opcConcatStr:
       decodeBC(rkNode)
       createStr regs[ra]
@@ -1532,10 +1537,10 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): TFullReg =
       # Set the `name` field of the exception
       var exceptionNameNode = newStrNode(nkStrLit, c.currentExceptionA.typ.sym.name.s)
       if c.currentExceptionA[2].kind == nkExprColonExpr:
-        exceptionNameNode.typ = c.currentExceptionA[2][1].typ
+        exceptionNameNode.typ() = c.currentExceptionA[2][1].typ
         c.currentExceptionA[2][1] = exceptionNameNode
       else:
-        exceptionNameNode.typ = c.currentExceptionA[2].typ
+        exceptionNameNode.typ() = c.currentExceptionA[2].typ
         c.currentExceptionA[2] = exceptionNameNode
       c.exceptionInstr = pc
 
@@ -1577,7 +1582,7 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): TFullReg =
       let instr2 = c.code[pc]
       let count = regs[instr2.regA].intVal.int
       regs[ra].node = newNodeI(nkBracket, c.debug[pc])
-      regs[ra].node.typ = typ
+      regs[ra].node.typ() = typ
       newSeq(regs[ra].node.sons, count)
       for i in 0..<count:
         regs[ra].node[i] = getNullValue(c, typ.elementType, c.debug[pc], c.config)
@@ -1992,7 +1997,7 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): TFullReg =
       else:
         internalAssert c.config, false
       regs[ra].node.info = n.info
-      regs[ra].node.typ = n.typ
+      regs[ra].node.typ() = n.typ
     of opcNCopyLineInfo:
       decodeB(rkNode)
       regs[ra].node.info = regs[rb].node.info
@@ -2072,7 +2077,7 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): TFullReg =
         ensureKind(rkNode)
         regs[ra].node = temp
         regs[ra].node.info = c.debug[pc]
-      regs[ra].node.typ = typ
+      regs[ra].node.typ() = typ
     of opcConv:
       let rb = instr.regB
       inc pc
@@ -2332,9 +2337,17 @@ proc execProc*(c: PCtx; sym: PSym; args: openArray[PNode]): PNode =
     localError(c.config, sym.info,
       "NimScript: attempt to call non-routine: " & sym.name.s)
 
+proc errorNode(idgen: IdGenerator; owner: PSym, n: PNode): PNode =
+  result = newNodeI(nkEmpty, n.info)
+  result.typ() = newType(tyError, idgen, owner)
+  result.typ.flags.incl tfCheckedForDestructor
+
 proc evalStmt*(c: PCtx, n: PNode) =
   let n = transformExpr(c.graph, c.idgen, c.module, n)
   let start = genStmt(c, n)
+  if c.cannotEval:
+    c.cannotEval = false
+    return
   # execute new instructions; this redundant opcEof check saves us lots
   # of allocations in 'execute':
   if c.code[start].opcode != opcEof:
@@ -2345,7 +2358,10 @@ proc evalExpr*(c: PCtx, n: PNode): PNode =
   # `nim --eval:"expr"` might've used it at some point for idetools; could
   # be revived for nimsuggest
   let n = transformExpr(c.graph, c.idgen, c.module, n)
+  c.cannotEval = false
   let start = genExpr(c, n)
+  if c.cannotEval:
+    return errorNode(c.idgen, c.module, n)
   assert c.code[start].opcode != opcEof
   result = execute(c, start)
 
@@ -2398,7 +2414,10 @@ proc evalConstExprAux(module: PSym; idgen: IdGenerator;
   var c = PCtx g.vm
   let oldMode = c.mode
   c.mode = mode
+  c.cannotEval = false
   let start = genExpr(c, n, requiresValue = mode!=emStaticStmt)
+  if c.cannotEval:
+    return errorNode(idgen, prc, n)
   if c.code[start].opcode == opcEof: return newNodeI(nkEmpty, n.info)
   assert c.code[start].opcode != opcEof
   when debugEchoCode: c.echoCode start
@@ -2455,7 +2474,7 @@ proc setupMacroParam(x: PNode, typ: PType): TFullReg =
     var n = x
     if n.kind in {nkHiddenSubConv, nkHiddenStdConv}: n = n[1]
     n.flags.incl nfIsRef
-    n.typ = x.typ
+    n.typ() = x.typ
     result = TFullReg(kind: rkNode, node: n)
 
 iterator genericParamsInMacroCall*(macroSym: PSym, call: PNode): (PSym, PNode) =
@@ -2469,11 +2488,6 @@ iterator genericParamsInMacroCall*(macroSym: PSym, call: PNode): (PSym, PNode) =
 # to prevent endless recursion in macro instantiation
 const evalMacroLimit = 1000
 
-#proc errorNode(idgen: IdGenerator; owner: PSym, n: PNode): PNode =
-#  result = newNodeI(nkEmpty, n.info)
-#  result.typ = newType(tyError, idgen, owner)
-#  result.typ.flags.incl tfCheckedForDestructor
-
 proc evalMacroCall*(module: PSym; idgen: IdGenerator; g: ModuleGraph; templInstCounter: ref int;
                     n, nOrig: PNode, sym: PSym): PNode =
   #if g.config.errorCounter > 0: return errorNode(idgen, module, n)
@@ -2497,7 +2511,10 @@ proc evalMacroCall*(module: PSym; idgen: IdGenerator; g: ModuleGraph; templInstC
   c.comesFromHeuristic.line = 0'u16
   c.callsite = nOrig
   c.templInstCounter = templInstCounter
+  c.cannotEval = false
   let start = genProc(c, sym)
+  if c.cannotEval:
+    return errorNode(idgen, module, n)
 
   var tos = PStackFrame(prc: sym, comesFrom: 0, next: nil)
   let maxSlots = sym.offset
diff --git a/compiler/vmdef.nim b/compiler/vmdef.nim
index bdb0aeed15..bfa589402a 100644
--- a/compiler/vmdef.nim
+++ b/compiler/vmdef.nim
@@ -100,7 +100,7 @@ type
     opcEqRef, opcEqNimNode, opcSameNodeType,
     opcXor, opcNot, opcUnaryMinusInt, opcUnaryMinusFloat, opcBitnotInt,
     opcEqStr, opcEqCString, opcLeStr, opcLtStr, opcEqSet, opcLeSet, opcLtSet,
-    opcMulSet, opcPlusSet, opcMinusSet, opcConcatStr,
+    opcMulSet, opcPlusSet, opcMinusSet, opcXorSet, opcConcatStr,
     opcContainsSet, opcRepr, opcSetLenStr, opcSetLenSeq,
     opcIsNil, opcOf, opcIs,
     opcParseFloat, opcConv, opcCast,
@@ -270,6 +270,7 @@ type
     templInstCounter*: ref int # gives every template instantiation a unique ID, needed here for getAst
     vmstateDiff*: seq[(PSym, PNode)] # we remember the "diff" to global state here (feature for IC)
     procToCodePos*: Table[int, int]
+    cannotEval*: bool
 
   PStackFrame* = ref TStackFrame
   TStackFrame* {.acyclic.} = object
diff --git a/compiler/vmdeps.nim b/compiler/vmdeps.nim
index 294aaaa795..2a088ac964 100644
--- a/compiler/vmdeps.nim
+++ b/compiler/vmdeps.nim
@@ -35,7 +35,7 @@ proc atomicTypeX(cache: IdentCache; name: string; m: TMagic; t: PType; info: TLi
   sym.magic = m
   sym.typ = t
   result = newSymNode(sym)
-  result.typ = t
+  result.typ() = t
 
 proc atomicTypeX(s: PSym; info: TLineInfo): PNode =
   result = newSymNode(s)
@@ -52,7 +52,7 @@ proc mapTypeToBracketX(cache: IdentCache; name: string; m: TMagic; t: PType; inf
   for a in t.kids:
     if a == nil:
       let voidt = atomicTypeX(cache, "void", mVoid, t, info, idgen)
-      voidt.typ = newType(tyVoid, idgen, t.owner)
+      voidt.typ() = newType(tyVoid, idgen, t.owner)
       result.add voidt
     else:
       result.add mapTypeToAstX(cache, a, info, idgen, inst)
@@ -136,7 +136,7 @@ proc mapTypeToAstX(cache: IdentCache; t: PType; info: TLineInfo;
       if allowRecursion:
         result = mapTypeToAstR(t.skipModifier, info)
         # keep original type info for getType calls on the output node:
-        result.typ = t
+        result.typ() = t
       else:
         result = newNodeX(nkBracketExpr)
         #result.add mapTypeToAst(t.last, info)
@@ -146,7 +146,7 @@ proc mapTypeToAstX(cache: IdentCache; t: PType; info: TLineInfo;
     else:
       result = mapTypeToAstX(cache, t.skipModifier, info, idgen, inst, allowRecursion)
       # keep original type info for getType calls on the output node:
-      result.typ = t
+      result.typ() = t
   of tyGenericBody:
     if inst:
       result = mapTypeToAstR(t.typeBodyImpl, info)
diff --git a/compiler/vmgen.nim b/compiler/vmgen.nim
index 0c7a49984f..59b8bf17f7 100644
--- a/compiler/vmgen.nim
+++ b/compiler/vmgen.nim
@@ -1212,6 +1212,7 @@ proc genMagic(c: PCtx; n: PNode; dest: var TDest; flags: TGenFlags = {}, m: TMag
   of mMulSet: genBinarySet(c, n, dest, opcMulSet)
   of mPlusSet: genBinarySet(c, n, dest, opcPlusSet)
   of mMinusSet: genBinarySet(c, n, dest, opcMinusSet)
+  of mXorSet: genBinarySet(c, n, dest, opcXorSet)
   of mConStrStr: genVarargsABC(c, n, dest, opcConcatStr)
   of mInSet: genBinarySet(c, n, dest, opcContainsSet)
   of mRepr: genUnaryABC(c, n, dest, opcRepr)
@@ -1473,9 +1474,9 @@ proc canElimAddr(n: PNode; idgen: IdGenerator): PNode =
       result = copyNode(n[0])
       result.add m[0]
       if n.typ.skipTypes(abstractVar).kind != tyOpenArray:
-        result.typ = n.typ
+        result.typ() = n.typ
       elif n.typ.skipTypes(abstractInst).kind in {tyVar}:
-        result.typ = toVar(result.typ, n.typ.skipTypes(abstractInst).kind, idgen)
+        result.typ() = toVar(result.typ, n.typ.skipTypes(abstractInst).kind, idgen)
   of nkHiddenStdConv, nkHiddenSubConv, nkConv:
     var m = n[0][1]
     if m.kind in {nkDerefExpr, nkHiddenDeref}:
@@ -1484,9 +1485,9 @@ proc canElimAddr(n: PNode; idgen: IdGenerator): PNode =
       result.add n[0][0]
       result.add m[0]
       if n.typ.skipTypes(abstractVar).kind != tyOpenArray:
-        result.typ = n.typ
+        result.typ() = n.typ
       elif n.typ.skipTypes(abstractInst).kind in {tyVar}:
-        result.typ = toVar(result.typ, n.typ.skipTypes(abstractInst).kind, idgen)
+        result.typ() = toVar(result.typ, n.typ.skipTypes(abstractInst).kind, idgen)
   else:
     if n[0].kind in {nkDerefExpr, nkHiddenDeref}:
       # addr ( deref ( x )) --> x
@@ -1545,6 +1546,7 @@ template cannotEval(c: PCtx; n: PNode) =
   if c.config.cmd == cmdCheck:
     localError(c.config, n.info, "cannot evaluate at compile time: " & 
     n.renderTree)
+    c.cannotEval = true
     return
   globalError(c.config, n.info, "cannot evaluate at compile time: " &
     n.renderTree)
@@ -1678,7 +1680,7 @@ proc genAsgn(c: PCtx; le, ri: PNode; requiresCopy: bool) =
 
 proc genTypeLit(c: PCtx; t: PType; dest: var TDest) =
   var n = newNode(nkType)
-  n.typ = t
+  n.typ() = t
   genLit(c, n, dest)
 
 proc isEmptyBody(n: PNode): bool =
@@ -1847,7 +1849,7 @@ proc genCheckedObjAccessAux(c: PCtx; n: PNode; dest: var TDest; flags: TGenFlags
   let fieldName = $accessExpr[1]
   let msg = genFieldDefect(c.config, fieldName, disc.sym)
   let strLit = newStrNode(msg, accessExpr[1].info)
-  strLit.typ = strType
+  strLit.typ() = strType
   c.genLit(strLit, msgReg)
   c.gABC(n, opcInvalidField, msgReg, discVal)
   c.freeTemp(discVal)
diff --git a/compiler/vtables.nim b/compiler/vtables.nim
index 928c64dd57..6d481fbb3c 100644
--- a/compiler/vtables.nim
+++ b/compiler/vtables.nim
@@ -33,13 +33,13 @@ proc dispatch(x: Base, params: ...) =
     dispatchObject,
     newIntNode(nkIntLit, index)
   )
-  getVTableCall.typ = base.typ
+  getVTableCall.typ() = base.typ
   var vTableCall = newNodeIT(nkCall, base.info, base.typ.returnType)
   var castNode = newTree(nkCast,
         newNodeIT(nkType, base.info, base.typ),
         getVTableCall)
 
-  castNode.typ = base.typ
+  castNode.typ() = base.typ
   vTableCall.add castNode
   for col in 1..<paramLen:
     let param = base.typ.n[col].sym
diff --git a/doc/manual.md b/doc/manual.md
index 236c19b0e7..d3c81aa78f 100644
--- a/doc/manual.md
+++ b/doc/manual.md
@@ -2241,6 +2241,10 @@ Nim supports these `calling conventions`:idx:\:
     only a hint for the compiler: it may completely ignore it, and
     it may inline procedures that are not marked as `inline`.
 
+`noinline`:idx:
+:   The backend compiler may inline procedures that are not marked as `inline`.
+    The noinline convention prevents it.
+
 `fastcall`:idx:
 :   Fastcall means different things to different C compilers. One gets whatever
     the C `__fastcall` means.
@@ -8646,6 +8650,14 @@ pragma should be used in addition to the `exportc` pragma. See
 [Dynlib pragma for export].
 
 
+Exportcpp pragma
+----------------
+The `exportcpp` pragma works like the `exportc` pragma but it requires the `cpp` backend.
+When compiled with the `cpp` backend, the `exportc` pragma adds `export "C"` to
+the declaration in the generated code so that it can be called from both C and
+C++ code. `exportcpp` pragma doesn't add `export "C"`.
+
+
 Extern pragma
 -------------
 Like `exportc` or `importc`, the `extern` pragma affects name
diff --git a/doc/tut1.md b/doc/tut1.md
index 2e83effa3b..3eaa1b1610 100644
--- a/doc/tut1.md
+++ b/doc/tut1.md
@@ -1182,6 +1182,9 @@ at runtime by 0, the second by 1, and so on. For example:
 
   var x = south     # `x` is of type `Direction`; its value is `south`
   echo x            # prints "south"
+
+  if x == Direction.south:
+    echo "It's south!"
   ```
 
 All the comparison operators can be used with enumeration types.
diff --git a/lib/nimbase.h b/lib/nimbase.h
index 258bf8862f..f64bdd8951 100644
--- a/lib/nimbase.h
+++ b/lib/nimbase.h
@@ -469,12 +469,6 @@ typedef char* NCSTRING;
 
 #define NIM_STRLIT_FLAG ((NU)(1) << ((NIM_INTBITS) - 2)) /* This has to be the same as system.strlitFlag! */
 
-#define STRING_LITERAL(name, str, length) \
-   static const struct {                   \
-     TGenericSeq Sup;                      \
-     NIM_CHAR data[(length) + 1];          \
-  } name = {{length, (NI) ((NU)length | NIM_STRLIT_FLAG)}, str}
-
 /* declared size of a sequence/variable length array: */
 #if defined(__cplusplus) && defined(__clang__)
 #  define SEQ_DECL_SIZE 1
diff --git a/lib/std/setutils.nim b/lib/std/setutils.nim
index 8e7bc6a92d..32a2e88f2c 100644
--- a/lib/std/setutils.nim
+++ b/lib/std/setutils.nim
@@ -75,3 +75,31 @@ func `[]=`*[T](t: var set[T], key: T, val: bool) {.inline.} =
     s[a3] = true
     assert s == {a2, a3}
   if val: t.incl key else: t.excl key
+
+when defined(nimHasXorSet):
+  func symmetricDifference*[T](x, y: set[T]): set[T] {.magic: "XorSet".} =
+    ## This operator computes the symmetric difference of two sets,
+    ## equivalent to but more efficient than `x + y - x * y` or
+    ## `(x - y) + (y - x)`.
+    runnableExamples:
+      assert symmetricDifference({1, 2, 3}, {2, 3, 4}) == {1, 4}
+else:
+  func symmetricDifference*[T](x, y: set[T]): set[T] {.inline.} =
+    result = x + y - (x * y)
+
+proc `-+-`*[T](x, y: set[T]): set[T] {.inline.} =
+  ## Operator alias for `symmetricDifference`.
+  runnableExamples:
+    assert {1, 2, 3} -+- {2, 3, 4} == {1, 4}
+  result = symmetricDifference(x, y)
+
+proc toggle*[T](x: var set[T], y: set[T]) {.inline.} =
+  ## Toggles the existence of each value of `y` in `x`.
+  ## If any element in `y` is also in `x`, it is excluded from `x`;
+  ## otherwise it is included.
+  ## Equivalent to `x = symmetricDifference(x, y)`.
+  runnableExamples:
+    var x = {1, 2, 3}
+    x.toggle({2, 3, 4})
+    assert x == {1, 4}
+  x = symmetricDifference(x, y)
diff --git a/lib/system/jssys.nim b/lib/system/jssys.nim
index 5599240fdb..ec1af2ea57 100644
--- a/lib/system/jssys.nim
+++ b/lib/system/jssys.nim
@@ -337,6 +337,18 @@ proc SetMinus(a, b: int): int {.compilerproc, asmNoStackFrame.} =
     return result;
   """.}
 
+proc SetXor(a, b: int): int {.compilerproc, asmNoStackFrame.} =
+  {.emit: """
+    var result = {};
+    for (var elem in `a`) {
+      if (!`b`[elem]) { result[elem] = true; }
+    }
+    for (var elem in `b`) {
+      if (!`a`[elem]) { result[elem] = true; }
+    }
+    return result;
+  """.}
+
 proc cmpStrings(a, b: string): int {.asmNoStackFrame, compilerproc.} =
   {.emit: """
     if (`a` == `b`) return 0;
diff --git a/lib/system_overview.rst b/lib/system_overview.rst
index cc0643bf16..50046b9e33 100644
--- a/lib/system_overview.rst
+++ b/lib/system_overview.rst
@@ -9,6 +9,7 @@ is in separate files:
 * `assertions <assertions.html>`_
 * `dollars <dollars.html>`_
 * `ctypes <ctypes.html>`_
+* `repr_v2 <repr_v2.html>`_
 
 
 Here is a short overview of the most commonly used functions from the
diff --git a/testament/categories.nim b/testament/categories.nim
index 6a05fcf0ce..4704301b5f 100644
--- a/testament/categories.nim
+++ b/testament/categories.nim
@@ -449,7 +449,7 @@ proc testNimblePackages(r: var TResults; cat: Category; packageFilter: string) =
           if pkg.allowFailure:
             inc r.passed
             inc r.failedButAllowed
-          addResult(r, test, targetC, "", "", cmd & "\n" & outp, reFailed, allowFailure = pkg.allowFailure)
+          r.finishTest(test, targetC, "", "", cmd & "\n" & outp, reFailed, allowFailure = pkg.allowFailure)
           continue
         outp
 
@@ -465,21 +465,21 @@ proc testNimblePackages(r: var TResults; cat: Category; packageFilter: string) =
         discard tryCommand(cmds[i], maxRetries = 3)
       discard tryCommand(cmds[^1], reFailed = reBuildFailed)
       inc r.passed
-      r.addResult(test, targetC, "", "", "", reSuccess, allowFailure = pkg.allowFailure)
+      r.finishTest(test, targetC, "", "", "", reSuccess, allowFailure = pkg.allowFailure)
 
     errors = r.total - r.passed
     if errors == 0:
-      r.addResult(packageFileTest, targetC, "", "", "", reSuccess)
+      r.finishTest(packageFileTest, targetC, "", "", "", reSuccess)
     else:
-      r.addResult(packageFileTest, targetC, "", "", "", reBuildFailed)
+      r.finishTest(packageFileTest, targetC, "", "", "", reBuildFailed)
 
   except JsonParsingError:
     errors = 1
-    r.addResult(packageFileTest, targetC, "", "", "Invalid package file", reBuildFailed)
+    r.finishTest(packageFileTest, targetC, "", "", "Invalid package file", reBuildFailed)
     raise
   except ValueError:
     errors = 1
-    r.addResult(packageFileTest, targetC, "", "", "Unknown package", reBuildFailed)
+    r.finishTest(packageFileTest, targetC, "", "", "Unknown package", reBuildFailed)
     raise # bug #18805
   finally:
     if errors == 0: removeDir(packagesDir)
@@ -568,6 +568,7 @@ proc isJoinableSpec(spec: TSpec): bool =
     spec.err != reDisabled and
     not spec.unjoinable and
     spec.exitCode == 0 and
+    spec.retries == 0 and
     spec.input.len == 0 and
     spec.nimout.len == 0 and
     spec.nimoutFull == false and
diff --git a/testament/important_packages.nim b/testament/important_packages.nim
index 1a9837ee0f..9bab3fe434 100644
--- a/testament/important_packages.nim
+++ b/testament/important_packages.nim
@@ -61,7 +61,7 @@ pkg "constantine", "nimble make_lib"
 pkg "cowstrings", "nim c -r tests/tcowstrings.nim"
 pkg "criterion"
 pkg "dashing", "nim c tests/functional.nim"
-pkg "datamancer", url = "https://github.com/nim-lang/Datamancer"
+pkg "datamancer"
 pkg "delaunay"
 pkg "docopt"
 pkg "dotenv"
diff --git a/testament/specs.nim b/testament/specs.nim
index c3040c1d8f..1a50f5eb17 100644
--- a/testament/specs.nim
+++ b/testament/specs.nim
@@ -56,6 +56,7 @@ type
     reJoined,          # test is disabled because it was joined into the megatest
     reSuccess          # test was successful
     reInvalidSpec      # test had problems to parse the spec
+    reRetry            # test is being retried
 
   TTarget* = enum
     targetC = "c"
@@ -102,6 +103,7 @@ type
                       # but don't rely on much precision
     inlineErrors*: seq[InlineError] # line information to error message
     debugInfo*: string # debug info to give more context
+    retries*: int # number of retry attempts after the test fails
 
 proc getCmd*(s: TSpec): string =
   if s.cmd.len == 0:
@@ -477,6 +479,8 @@ proc parseSpec*(filename: string): TSpec =
           result.timeout = parseFloat(e.value)
         except ValueError:
           result.parseErrors.addLine "cannot interpret as a float: ", e.value
+      of "retries":
+        discard parseInt(e.value, result.retries)
       of "targets", "target":
         try:
           result.targets.incl parseTargets(e.value)
diff --git a/testament/testament.nim b/testament/testament.nim
index 1e892e6367..9bea815eab 100644
--- a/testament/testament.nim
+++ b/testament/testament.nim
@@ -275,16 +275,13 @@ proc testName(test: TTest, target: TTarget, extraOptions: string, allowFailure:
   name.strip()
 
 proc addResult(r: var TResults, test: TTest, target: TTarget,
-               extraOptions, expected, given: string, successOrig: TResultEnum,
+               extraOptions, expected, given: string, success: TResultEnum, duration: float,
                allowFailure = false, givenSpec: ptr TSpec = nil) =
   # instead of `ptr TSpec` we could also use `Option[TSpec]`; passing `givenSpec` makes it easier to get what we need
   # instead of having to pass individual fields, or abusing existing ones like expected vs given.
   # test.name is easier to find than test.name.extractFilename
   # A bit hacky but simple and works with tests/testament/tshould_not_work.nim
   let name = testName(test, target, extraOptions, allowFailure)
-  let duration = epochTime() - test.startTime
-  let success = if test.spec.timeout > 0.0 and duration > test.spec.timeout: reTimeout
-                else: successOrig
 
   let durationStr = duration.formatFloat(ffDecimal, precision = 2).align(5)
   if backendLogging:
@@ -345,6 +342,33 @@ proc addResult(r: var TResults, test: TTest, target: TTarget,
       discard waitForExit(p)
       close(p)
 
+proc finishTest(r: var TResults, test: TTest, target: TTarget,
+                extraOptions, expected, given: string, successOrig: TResultEnum,
+                allowFailure = false, givenSpec: ptr TSpec = nil) =
+  ## calculates duration of test, reports result
+  ## `retries` option in the test is ignored
+  let duration = epochTime() - test.startTime
+  let success = if test.spec.timeout > 0.0 and duration > test.spec.timeout: reTimeout
+                else: successOrig
+  addResult(r, test, target, extraOptions, expected, given, success, duration, allowFailure, givenSpec)
+
+proc finishTestRetryable(r: var TResults, test: TTest, target: TTarget,
+                         extraOptions, expected, given: string, successOrig: TResultEnum,
+                         allowFailure = false, givenSpec: ptr TSpec = nil): bool =
+  ## if test failed and has remaining retries, return `true`,
+  ## otherwise calculate duration and report result
+  ## 
+  ## warning: if `true` is returned, then the result is not reported,
+  ## it has to be retried or `finishTest` should be called instead 
+  result = false
+  let duration = epochTime() - test.startTime
+  let success = if test.spec.timeout > 0.0 and duration > test.spec.timeout: reTimeout
+                else: successOrig
+  if test.spec.retries > 0 and success notin {reSuccess, reDisabled, reJoined, reInvalidSpec}:
+    return true
+  else:
+    addResult(r, test, target, extraOptions, expected, given, success, duration, allowFailure, givenSpec)
+
 proc toString(inlineError: InlineError, filename: string): string =
   result.add "$file($line, $col) $kind: $msg" % [
     "file", filename,
@@ -373,23 +397,24 @@ proc nimoutCheck(expected, given: TSpec): bool =
     result = false
 
 proc cmpMsgs(r: var TResults, expected, given: TSpec, test: TTest,
-             target: TTarget, extraOptions: string) =
+             target: TTarget, extraOptions: string): bool =
+  # result has to be checked for retry
   if not checkForInlineErrors(expected, given) or
     (not expected.nimoutFull and not nimoutCheck(expected, given)):
-      r.addResult(test, target, extraOptions, expected.nimout & inlineErrorsMsgs(expected), given.nimout, reMsgsDiffer)
+      result = r.finishTestRetryable(test, target, extraOptions, expected.nimout & inlineErrorsMsgs(expected), given.nimout, reMsgsDiffer)
   elif strip(expected.msg) notin strip(given.msg):
-    r.addResult(test, target, extraOptions, expected.msg, given.msg, reMsgsDiffer)
+    result = r.finishTestRetryable(test, target, extraOptions, expected.msg, given.msg, reMsgsDiffer)
   elif not nimoutCheck(expected, given):
-    r.addResult(test, target, extraOptions, expected.nimout, given.nimout, reMsgsDiffer)
+    result = r.finishTestRetryable(test, target, extraOptions, expected.nimout, given.nimout, reMsgsDiffer)
   elif extractFilename(expected.file) != extractFilename(given.file) and
       "internal error:" notin expected.msg:
-    r.addResult(test, target, extraOptions, expected.file, given.file, reFilesDiffer)
+    result = r.finishTestRetryable(test, target, extraOptions, expected.file, given.file, reFilesDiffer)
   elif expected.line != given.line and expected.line != 0 or
        expected.column != given.column and expected.column != 0:
-    r.addResult(test, target, extraOptions, $expected.line & ':' & $expected.column,
+    result = r.finishTestRetryable(test, target, extraOptions, $expected.line & ':' & $expected.column,
                       $given.line & ':' & $given.column, reLinesDiffer)
   else:
-    r.addResult(test, target, extraOptions, expected.msg, given.msg, reSuccess)
+    result = r.finishTestRetryable(test, target, extraOptions, expected.msg, given.msg, reSuccess)
     inc(r.passed)
 
 proc generatedFile(test: TTest, target: TTarget): string =
@@ -428,7 +453,8 @@ proc codegenCheck(test: TTest, target: TTarget, spec: TSpec, expectedMsg: var st
     echo getCurrentExceptionMsg()
 
 proc compilerOutputTests(test: TTest, target: TTarget, extraOptions: string,
-                         given: var TSpec, expected: TSpec; r: var TResults) =
+                         given: var TSpec, expected: TSpec; r: var TResults): bool =
+  # result has to be checked for retry
   var expectedmsg: string = ""
   var givenmsg: string = ""
   if given.err == reSuccess:
@@ -443,7 +469,7 @@ proc compilerOutputTests(test: TTest, target: TTarget, extraOptions: string,
   else:
     givenmsg = "$ " & given.cmd & '\n' & given.nimout
   if given.err == reSuccess: inc(r.passed)
-  r.addResult(test, target, extraOptions, expectedmsg, givenmsg, given.err)
+  result = r.finishTestRetryable(test, target, extraOptions, expectedmsg, givenmsg, given.err)
 
 proc getTestSpecTarget(): TTarget =
   if getEnv("NIM_COMPILE_TO_CPP", "false") == "true":
@@ -459,31 +485,39 @@ proc equalModuloLastNewline(a, b: string): bool =
 
 proc testSpecHelper(r: var TResults, test: var TTest, expected: TSpec,
                     target: TTarget, extraOptions: string, nimcache: string) =
-  test.startTime = epochTime()
+  template maybeRetry(x: bool) =
+    # if `x` is true, retries the test
+    if x:
+      test.spec.err = reRetry
+      dec test.spec.retries
+      testSpecHelper(r, test, expected, target, extraOptions, nimcache)
+      return
+  if test.spec.err != reRetry:
+    test.startTime = epochTime()
   if testName(test, target, extraOptions, false) in skips:
     test.spec.err = reDisabled
 
   if test.spec.err in {reDisabled, reJoined}:
-    r.addResult(test, target, extraOptions, "", "", test.spec.err)
+    r.finishTest(test, target, extraOptions, "", "", test.spec.err)
     inc(r.skipped)
     return
   var given = callNimCompiler(expected.getCmd, test.name, test.options, nimcache, target, extraOptions)
   case expected.action
   of actionCompile:
-    compilerOutputTests(test, target, extraOptions, given, expected, r)
+    maybeRetry compilerOutputTests(test, target, extraOptions, given, expected, r)
   of actionRun:
     if given.err != reSuccess:
-      r.addResult(test, target, extraOptions, "", "$ " & given.cmd & '\n' & given.nimout, given.err, givenSpec = given.addr)
+      maybeRetry r.finishTestRetryable(test, target, extraOptions, "", "$ " & given.cmd & '\n' & given.nimout, given.err, givenSpec = given.addr)
     else:
       let isJsTarget = target == targetJS
       var exeFile = changeFileExt(test.name, if isJsTarget: "js" else: ExeExt)
       if not fileExists(exeFile):
-        r.addResult(test, target, extraOptions, expected.output,
+        maybeRetry r.finishTestRetryable(test, target, extraOptions, expected.output,
                     "executable not found: " & exeFile, reExeNotFound)
       else:
         let nodejs = if isJsTarget: findNodeJs() else: ""
         if isJsTarget and nodejs == "":
-          r.addResult(test, target, extraOptions, expected.output, "nodejs binary not in PATH",
+          maybeRetry r.finishTestRetryable(test, target, extraOptions, expected.output, "nodejs binary not in PATH",
                       reExeNotFound)
         else:
           var exeCmd: string
@@ -515,19 +549,19 @@ proc testSpecHelper(r: var TResults, test: var TTest, expected: TSpec,
               buf
           if exitCode != expected.exitCode:
             given.err = reExitcodesDiffer
-            r.addResult(test, target, extraOptions, "exitcode: " & $expected.exitCode,
+            maybeRetry r.finishTestRetryable(test, target, extraOptions, "exitcode: " & $expected.exitCode,
                               "exitcode: " & $exitCode & "\n\nOutput:\n" &
                               bufB, reExitcodesDiffer)
           elif (expected.outputCheck == ocEqual and not expected.output.equalModuloLastNewline(bufB)) or
               (expected.outputCheck == ocSubstr and expected.output notin bufB):
             given.err = reOutputsDiffer
-            r.addResult(test, target, extraOptions, expected.output, bufB, reOutputsDiffer)
-          compilerOutputTests(test, target, extraOptions, given, expected, r)
+            maybeRetry r.finishTestRetryable(test, target, extraOptions, expected.output, bufB, reOutputsDiffer)
+          maybeRetry compilerOutputTests(test, target, extraOptions, given, expected, r)
   of actionReject:
     # Make sure its the compiler rejecting and not the system (e.g. segfault)
-    cmpMsgs(r, expected, given, test, target, extraOptions)
+    maybeRetry cmpMsgs(r, expected, given, test, target, extraOptions)
     if given.exitCode != QuitFailure:
-      r.addResult(test, target, extraOptions, "exitcode: " & $QuitFailure,
+      maybeRetry r.finishTestRetryable(test, target, extraOptions, "exitcode: " & $QuitFailure,
                         "exitcode: " & $given.exitCode & "\n\nOutput:\n" &
                         given.nimout, reExitcodesDiffer)
 
@@ -552,7 +586,7 @@ proc targetHelper(r: var TResults, test: TTest, expected: TSpec, extraOptions: s
   for target in expected.targets:
     inc(r.total)
     if target notin gTargets:
-      r.addResult(test, target, extraOptions, "", "", reDisabled)
+      r.finishTest(test, target, extraOptions, "", "", reDisabled)
       inc(r.skipped)
     elif simulate:
       inc count
@@ -567,7 +601,7 @@ proc testSpec(r: var TResults, test: TTest, targets: set[TTarget] = {}) =
   var expected = test.spec
   if expected.parseErrors.len > 0:
     # targetC is a lie, but a parameter is required
-    r.addResult(test, targetC, "", "", expected.parseErrors, reInvalidSpec)
+    r.finishTest(test, targetC, "", "", expected.parseErrors, reInvalidSpec)
     inc(r.total)
     return
 
diff --git a/testament/tests/shouldfail/tnotenoughretries.nim b/testament/tests/shouldfail/tnotenoughretries.nim
new file mode 100644
index 0000000000..20eda20754
--- /dev/null
+++ b/testament/tests/shouldfail/tnotenoughretries.nim
@@ -0,0 +1,20 @@
+discard """
+  retries: 1
+"""
+
+import os
+
+const tempFile = "tnotenoughretries_temp"
+
+if not fileExists(tempFile):
+  writeFile(tempFile, "abc")
+  quit(1)
+else:
+  let content = readFile(tempFile)
+  if content == "abc":
+    writeFile(tempFile, "def")
+    quit(1)
+  else:
+    # success
+    removeFile(tempFile)
+    discard
diff --git a/tests/ccgbugs/t19585.nim b/tests/ccgbugs/t19585.nim
new file mode 100644
index 0000000000..2a23738ec6
--- /dev/null
+++ b/tests/ccgbugs/t19585.nim
@@ -0,0 +1,13 @@
+discard """
+  targets: "c cpp"
+"""
+
+# bug #19585
+
+type
+  X* {.exportc.} = object
+    v: int
+
+{.emit:"""
+X x = { 1234 };
+""".}
\ No newline at end of file
diff --git a/tests/ccgbugs/timportc_distinct.nim b/tests/ccgbugs/timportc_distinct.nim
new file mode 100644
index 0000000000..afeadf33f9
--- /dev/null
+++ b/tests/ccgbugs/timportc_distinct.nim
@@ -0,0 +1,13 @@
+discard """
+  ccodecheck: "time_t"
+  joinable: false
+"""
+
+type
+  Time* {.importc: "time_t", header: "<time.h>".} = distinct clong
+
+proc foo =
+  var s: Time = default(Time)
+  discard s
+
+foo()
diff --git a/tests/ccgbugs/tunioninit.nim b/tests/ccgbugs/tunioninit.nim
new file mode 100644
index 0000000000..a58c8d27f6
--- /dev/null
+++ b/tests/ccgbugs/tunioninit.nim
@@ -0,0 +1,32 @@
+# issue #20653
+
+type
+  EmptySeq* {.bycopy.} = object
+
+  ChoiceWithEmptySeq_d* {.bycopy.} = object
+    a*: bool
+
+  INNER_C_UNION* {.bycopy, union.} = object
+    a*: char
+    b*: EmptySeq
+    c*: byte
+    d*: ChoiceWithEmptySeq_d
+
+  ChoiceWithEmptySeq_selection* = enum
+    ChoiceWithEmptySeq_NONE, 
+    ChoiceWithEmptySeq_a_PRESENT,
+    ChoiceWithEmptySeq_b_PRESENT,  
+    ChoiceWithEmptySeq_c_PRESENT,
+    ChoiceWithEmptySeq_d_PRESENT
+
+  ChoiceWithEmptySeq* {.bycopy.} = object
+    kind*: ChoiceWithEmptySeq_selection
+    u*: INNER_C_UNION
+
+  Og_Context* {.bycopy.} = object
+    state*: int
+    init_done*: bool
+    ch*: ChoiceWithEmptySeq
+    em*: EmptySeq
+
+var context* : Og_Context = Og_Context(init_done: false)
diff --git a/tests/destructor/tmove.nim b/tests/destructor/tmove.nim
index 2762aff900..da91442def 100644
--- a/tests/destructor/tmove.nim
+++ b/tests/destructor/tmove.nim
@@ -16,3 +16,16 @@ block:
     doAssert s == 2
 
   foo()
+
+import std/deques
+
+block: # bug #24319
+  var queue = initDeque[array[32, byte]]()
+  for i in 0 ..< 5:
+    let element: array[32, byte] = [
+            0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            0, 0, 0, 0, 0, 1,
+          ]
+    queue.addLast(element)
+
+  doAssert queue.popLast[^1] == byte(1)
diff --git a/tests/destructor/tuse_ownedref_after_move.nim b/tests/destructor/tuse_ownedref_after_move.nim
index 69348d5303..34d5be65a4 100644
--- a/tests/destructor/tuse_ownedref_after_move.nim
+++ b/tests/destructor/tuse_ownedref_after_move.nim
@@ -1,6 +1,6 @@
 discard """
   cmd: '''nim c --newruntime $file'''
-  errormsg: "'=copy' is not available for type <owned Button>; requires a copy because it's not the last read of ':envAlt.b1'; routine: main"
+  errormsg: "'=copy' is not available for type <owned Button>; requires a copy because it's not the last read of ':envAlt.b0'; routine: main"
   line: 48
 """
 
diff --git a/tests/errmsgs/t24258.nim b/tests/errmsgs/t24258.nim
new file mode 100644
index 0000000000..17466d4b2d
--- /dev/null
+++ b/tests/errmsgs/t24258.nim
@@ -0,0 +1,10 @@
+discard """
+  cmd: "nim check $file"
+  errormsg: "illformed AST: [22]43.len"
+  joinable: false
+"""
+
+template encodeList*(args: varargs[untyped]): seq[byte] =
+  @[byte args.len]
+
+let x = encodeList([22], 43)
\ No newline at end of file
diff --git a/tests/gc/bintrees.nim b/tests/gc/bintrees.nim
index 5b65bb4376..8c9324dad7 100644
--- a/tests/gc/bintrees.nim
+++ b/tests/gc/bintrees.nim
@@ -1,3 +1,7 @@
+discard """
+  retries: 2
+"""
+
 # -*- nim -*-
 
 import os, strutils
diff --git a/tests/gc/closureleak.nim b/tests/gc/closureleak.nim
index e67beb513d..d20452f956 100644
--- a/tests/gc/closureleak.nim
+++ b/tests/gc/closureleak.nim
@@ -1,6 +1,7 @@
 discard """
   outputsub: "true"
   disabled: "32bit"
+  retries: 2
 """
 
 type
diff --git a/tests/gc/cyclecollector.nim b/tests/gc/cyclecollector.nim
index 2d02a7a3c4..9cc1bbcee1 100644
--- a/tests/gc/cyclecollector.nim
+++ b/tests/gc/cyclecollector.nim
@@ -1,3 +1,6 @@
+discard """
+  retries: 2
+"""
 
 # Program to detect bug #1796 reliably
 
diff --git a/tests/gc/cycleleak.nim b/tests/gc/cycleleak.nim
index e355abc968..d774661e86 100644
--- a/tests/gc/cycleleak.nim
+++ b/tests/gc/cycleleak.nim
@@ -1,5 +1,6 @@
 discard """
   outputsub: "no leak: "
+  retries: 2
 """
 
 type
diff --git a/tests/gc/foreign_thr.nim b/tests/gc/foreign_thr.nim
index 88ab951133..2709261c11 100644
--- a/tests/gc/foreign_thr.nim
+++ b/tests/gc/foreign_thr.nim
@@ -6,6 +6,7 @@ Hello from thread
 Hello from thread
 '''
   cmd: "nim $target --hints:on --threads:on --tlsEmulation:off $options $file"
+  retries: 2
 """
 # Copied from stdlib
 import strutils
diff --git a/tests/gc/gcbench.nim b/tests/gc/gcbench.nim
index e29ea762d0..da339f6d4b 100644
--- a/tests/gc/gcbench.nim
+++ b/tests/gc/gcbench.nim
@@ -1,5 +1,6 @@
 discard """
   outputsub: "Success!"
+  retries: 2
 """
 
 # This is adapted from a benchmark written by John Ellis and Pete Kovac
diff --git a/tests/gc/gcemscripten.nim b/tests/gc/gcemscripten.nim
index cc12b230f1..4905027bc5 100644
--- a/tests/gc/gcemscripten.nim
+++ b/tests/gc/gcemscripten.nim
@@ -1,5 +1,6 @@
 discard """
   outputsub: "77\n77"
+  retries: 2
 """
 
 ## Check how GC/Alloc works in Emscripten
diff --git a/tests/gc/gcleak.nim b/tests/gc/gcleak.nim
index 0bf993968e..326f421429 100644
--- a/tests/gc/gcleak.nim
+++ b/tests/gc/gcleak.nim
@@ -1,5 +1,6 @@
 discard """
   outputsub: "no leak: "
+  retries: 2
 """
 
 when defined(GC_setMaxPause):
diff --git a/tests/gc/gcleak2.nim b/tests/gc/gcleak2.nim
index bc943dbe71..4bd5d57c4a 100644
--- a/tests/gc/gcleak2.nim
+++ b/tests/gc/gcleak2.nim
@@ -1,5 +1,6 @@
 discard """
   outputsub: "no leak: "
+  retries: 2
 """
 
 when defined(GC_setMaxPause):
diff --git a/tests/gc/gcleak3.nim b/tests/gc/gcleak3.nim
index 5e146d69f0..897d87382a 100644
--- a/tests/gc/gcleak3.nim
+++ b/tests/gc/gcleak3.nim
@@ -1,5 +1,6 @@
 discard """
   outputsub: "no leak: "
+  retries: 2
 """
 
 when defined(GC_setMaxPause):
diff --git a/tests/gc/gcleak4.nim b/tests/gc/gcleak4.nim
index a72db67b74..84a1ee943b 100644
--- a/tests/gc/gcleak4.nim
+++ b/tests/gc/gcleak4.nim
@@ -1,5 +1,6 @@
 discard """
   outputsub: "no leak: "
+  retries: 2
 """
 
 type
diff --git a/tests/gc/gcleak5.nim b/tests/gc/gcleak5.nim
index f1913831b4..f926b8ae67 100644
--- a/tests/gc/gcleak5.nim
+++ b/tests/gc/gcleak5.nim
@@ -1,5 +1,6 @@
 discard """
   output: "success"
+  retries: 2
 """
 
 import os, times
diff --git a/tests/gc/gctest.nim b/tests/gc/gctest.nim
index 78b78934c0..e970e557cd 100644
--- a/tests/gc/gctest.nim
+++ b/tests/gc/gctest.nim
@@ -1,5 +1,6 @@
 discard """
   outputsub: "finished"
+  retries: 2
 """
 
 # Test the garbage collector.
diff --git a/tests/gc/growobjcrash.nim b/tests/gc/growobjcrash.nim
index ff1aa7e98d..7101ae40b4 100644
--- a/tests/gc/growobjcrash.nim
+++ b/tests/gc/growobjcrash.nim
@@ -1,3 +1,7 @@
+discard """
+  retries: 2
+"""
+
 import std/[cgi, strtabs]
 
 proc handleRequest(query: string): StringTableRef =
diff --git a/tests/gc/refarrayleak.nim b/tests/gc/refarrayleak.nim
index 57b489721a..8c94e83287 100644
--- a/tests/gc/refarrayleak.nim
+++ b/tests/gc/refarrayleak.nim
@@ -1,5 +1,6 @@
 discard """
   outputsub: "no leak: "
+  retries: 2
 """
 
 type
diff --git a/tests/gc/stackrefleak.nim b/tests/gc/stackrefleak.nim
index 7f3fbff43d..b273bb8753 100644
--- a/tests/gc/stackrefleak.nim
+++ b/tests/gc/stackrefleak.nim
@@ -1,5 +1,6 @@
 discard """
   outputsub: "no leak: "
+  retries: 2
 """
 
 type
diff --git a/tests/gc/tdisable_orc.nim b/tests/gc/tdisable_orc.nim
index b5f161c791..d43da55664 100644
--- a/tests/gc/tdisable_orc.nim
+++ b/tests/gc/tdisable_orc.nim
@@ -1,5 +1,6 @@
 discard """
   joinable: false
+  retries: 2
 """
 
 import std/asyncdispatch
diff --git a/tests/gc/thavlak.nim b/tests/gc/thavlak.nim
index cfd860e258..f697a9eba9 100644
--- a/tests/gc/thavlak.nim
+++ b/tests/gc/thavlak.nim
@@ -8,6 +8,7 @@ Performing Loop Recognition
 Another 3 iterations...
 ...
 Found 1 loops (including artificial root node) (3)'''
+  retries: 2
 """
 
 # bug #3184
diff --git a/tests/gc/tlists.nim b/tests/gc/tlists.nim
index 959cc5f7c4..b9d5c07c33 100644
--- a/tests/gc/tlists.nim
+++ b/tests/gc/tlists.nim
@@ -1,5 +1,6 @@
 discard """
     output: '''Success'''
+    retries: 2
 """
 
 # bug #3793
diff --git a/tests/gc/trace_globals.nim b/tests/gc/trace_globals.nim
index f62a15692c..2d8eca2f4e 100644
--- a/tests/gc/trace_globals.nim
+++ b/tests/gc/trace_globals.nim
@@ -3,6 +3,7 @@ discard """
 10000000
 10000000
 10000000'''
+  retries: 2
 """
 
 # bug #17085
diff --git a/tests/gc/tregionleak.nim b/tests/gc/tregionleak.nim
index 277cfc9875..578ede01e4 100644
--- a/tests/gc/tregionleak.nim
+++ b/tests/gc/tregionleak.nim
@@ -4,6 +4,7 @@ discard """
 finalized
 finalized
 '''
+  retries: 2
 """
 
 proc finish(o: RootRef) =
diff --git a/tests/gc/weakrefs.nim b/tests/gc/weakrefs.nim
index 81c048d746..b20b364c5d 100644
--- a/tests/gc/weakrefs.nim
+++ b/tests/gc/weakrefs.nim
@@ -1,5 +1,6 @@
 discard """
   output: "true"
+  retries: 2
 """
 
 import intsets
diff --git a/tests/generics/tpointerprocs.nim b/tests/generics/tpointerprocs.nim
index 2bcaf15b36..29c4f2954f 100644
--- a/tests/generics/tpointerprocs.nim
+++ b/tests/generics/tpointerprocs.nim
@@ -2,10 +2,17 @@ discard """
 cmd: "nim check $options --hints:off $file"
 action: "reject"
 nimout:'''
-tpointerprocs.nim(15, 11) Error: 'foo' doesn't have a concrete type, due to unspecified generic parameters.
-tpointerprocs.nim(27, 11) Error: cannot instantiate: 'foo[int]'; got 1 typeof(s) but expected 2
-tpointerprocs.nim(27, 14) Error: expression 'foo[int]' has no type (or is ambiguous)
-tpointerprocs.nim(28, 11) Error: expression 'bar' has no type (or is ambiguous)
+tpointerprocs.nim(22, 11) Error: 'foo' doesn't have a concrete type, due to unspecified generic parameters.
+tpointerprocs.nim(34, 14) Error: type mismatch: got <int>
+but expected one of:
+proc foo(x: int | float; y: int or string): float
+  first type mismatch at position: 2 in generic parameters
+  missing generic parameter: y:type
+
+expression: foo[int]
+tpointerprocs.nim(34, 14) Error: cannot instantiate: 'foo[int]'
+tpointerprocs.nim(34, 14) Error: expression 'foo[int]' has no type (or is ambiguous)
+tpointerprocs.nim(35, 11) Error: expression 'bar' has no type (or is ambiguous)
 '''
 """
 
@@ -25,4 +32,4 @@ block:
   proc foo(x: int | float, y: int or string): float = result = 1.0
   let
     bar = foo[int]
-    baz = bar
\ No newline at end of file
+    baz = bar
diff --git a/tests/iter/tfoldedaddr.nim b/tests/iter/tfoldedaddr.nim
new file mode 100644
index 0000000000..cbf4ea5fa7
--- /dev/null
+++ b/tests/iter/tfoldedaddr.nim
@@ -0,0 +1,32 @@
+discard """
+  output: '''
+23
+23
+23
+23
+23
+23
+'''
+"""
+
+block: # issue #24305
+  iterator demo(a: openArray[int]): int =
+    for k in countUp(a[0], 19):
+      yield 23
+
+  for k in demo(@[17]):
+    echo k
+
+block: # issue #24305 with array
+  iterator demo(a: array[1, int]): int =
+    for k in countUp(a[0], 19):
+      yield 23
+
+  for k in demo([17]):
+    echo k
+
+block: # related regression
+  proc main =
+    let a = [0, 1, 2]
+    let x = addr a[low(a)]
+  main()
diff --git a/tests/iter/tnestedclosures.nim b/tests/iter/tnestedclosures.nim
new file mode 100644
index 0000000000..273c4aa303
--- /dev/null
+++ b/tests/iter/tnestedclosures.nim
@@ -0,0 +1,139 @@
+discard """
+  targets: "c"
+  output: '''
+Test 1:
+12
+Test 2:
+23
+23
+Test 3:
+34
+34
+Test 4:
+45
+45
+50
+50
+Test 5:
+45
+123
+47
+50
+Test 6:
+<hi>
+Test 7:
+0
+1
+2
+'''
+"""
+
+block: #24094
+  echo "Test 1:"
+  proc foo() =
+    let x = 12
+    iterator bar2(): int {.closure.} =
+      yield x
+    proc bar() =
+      let z = bar2
+      for y in z(): # just doing bar2() gives param not in env: x
+        echo y
+    bar()
+
+  foo()
+
+block: #24094
+  echo "Test 2:"
+  iterator foo(): int {.closure.} =
+    let x = 23
+    iterator bar2(): int {.closure.} =
+      yield x
+    proc bar() =
+      let z = bar2
+      for y in z():
+        echo y
+    bar()
+    yield x
+
+  for x in foo(): echo x
+
+block: #24094
+  echo "Test 3:"
+  iterator foo(): int {.closure.} =
+    let x = 34
+    proc bar() =
+      echo x
+    iterator bar2(): int {.closure.} =
+      bar()
+      yield x
+    for y in bar2():
+      yield y
+
+  for x in foo(): echo x
+
+block:
+  echo "Test 4:"
+  proc foo() =
+    var x = 45
+    iterator bar2(): int {.closure.} =
+      yield x
+      yield x + 3
+
+    let b1 = bar2
+    let b2 = bar2
+    echo b1()
+    echo b2()
+    x = 47
+    echo b1()
+    echo b2()
+  foo()
+
+block:
+  echo "Test 5:"
+  proc foo() =
+    var x = 45
+    iterator bar2(): int {.closure.} =
+      yield x
+      yield x + 3
+
+    proc bar() =
+      var y = 123
+      iterator bar3(): int {.closure.} =
+        yield x
+        yield y
+      let b3 = bar3
+      for z in b3():
+        echo z
+      x = 47
+      let b2 = bar2
+      for z in b2():
+        echo z
+    bar()
+  foo()
+
+block: #19154
+  echo "Test 6:"
+  proc test(s: string): proc(): iterator(): string =
+    iterator it(): string = yield s
+    proc f(): iterator(): string = it
+    return f
+
+  let it = test("hi")()
+  for s in it():
+    echo "<", s, ">"
+
+block: #3824
+  echo "Test 7:"
+  proc main =
+    iterator factory(): int {.closure.} =
+      iterator bar(): int {.closure.} =
+        yield 0
+        yield 1
+        yield 2
+
+      for x in bar(): yield x
+
+    for x in factory():
+      echo x
+
+  main()
diff --git a/tests/iter/tyieldintry.nim b/tests/iter/tyieldintry.nim
index e51ab7f0d5..04409795b0 100644
--- a/tests/iter/tyieldintry.nim
+++ b/tests/iter/tyieldintry.nim
@@ -1,5 +1,5 @@
 discard """
-  matrix: "; --experimental:strictdefs; -d:nimOptIters"
+  matrix: "; --experimental:strictdefs"
   targets: "c cpp"
 """
 
@@ -505,7 +505,7 @@ block: # void iterator
       discard
   var a = it
 
-if defined(nimOptIters): # Locals present in only 1 state should be on the stack
+block: # Locals present in only 1 state should be on the stack
   proc checkOnStack(a: pointer, shouldBeOnStack: bool) =
     # Quick and dirty way to check if a points to stack
     var dummy = 0
diff --git a/tests/overload/tambiguousexplicitgeneric.nim b/tests/overload/tambiguousexplicitgeneric.nim
new file mode 100644
index 0000000000..cc6e3dbe40
--- /dev/null
+++ b/tests/overload/tambiguousexplicitgeneric.nim
@@ -0,0 +1,6 @@
+# related to issue #8064
+
+import tables
+
+let x = values[int] #[tt.Error
+        ^ ambiguous identifier: 'values' -- use one of the following:]#
diff --git a/tests/overload/texplicitgenericdiscard.nim b/tests/overload/texplicitgenericdiscard.nim
new file mode 100644
index 0000000000..1a207849b6
--- /dev/null
+++ b/tests/overload/texplicitgenericdiscard.nim
@@ -0,0 +1,7 @@
+# issue #8064
+
+import tables
+
+values[int] #[tt.Error
+^ ambiguous identifier: 'values' -- use one of the following:]#
+# this happens before discard check, so no discard error
diff --git a/tests/stdlib/tsetutils.nim b/tests/stdlib/tsetutils.nim
index c8498f23e0..c3338a3a27 100644
--- a/tests/stdlib/tsetutils.nim
+++ b/tests/stdlib/tsetutils.nim
@@ -44,6 +44,26 @@ template main =
     s[a2] = true
     s[a3] = true
     doAssert s == {a2, a3}
+  
+  block: # set symmetric difference (xor), https://github.com/nim-lang/RFCs/issues/554
+    type T = set[range[0..15]]
+    let x: T = {1, 4, 5, 8, 9}
+    let y: T = {0, 2..6, 9}
+    let res = symmetricDifference(x, y)
+    doAssert res == {0, 1, 2, 3, 6, 8}
+    doAssert res == (x + y - x * y)
+    doAssert res == ((x - y) + (y - x))
+    var z = x
+    doAssert z == {1, 4, 5, 8, 9}
+    doAssert z == x
+    z.toggle(y)
+    doAssert z == res
+    z.toggle(y)
+    doAssert z == x
+    z.toggle({1, 5})
+    doAssert z == {4, 8, 9}
+    z.toggle({3, 8})
+    doAssert z == {3, 4, 9}
 
 main()
 static: main()
diff --git a/tests/testament/tretries.nim b/tests/testament/tretries.nim
new file mode 100644
index 0000000000..eaa5b1e916
--- /dev/null
+++ b/tests/testament/tretries.nim
@@ -0,0 +1,20 @@
+discard """
+  retries: 2
+"""
+
+import os
+
+const tempFile = "tretries_temp"
+
+if not fileExists(tempFile):
+  writeFile(tempFile, "abc")
+  quit(1)
+else:
+  let content = readFile(tempFile)
+  if content == "abc":
+    writeFile(tempFile, "def")
+    quit(1)
+  else:
+    # success
+    removeFile(tempFile)
+    discard
diff --git a/tests/testament/tshould_not_work.nim b/tests/testament/tshould_not_work.nim
index 8c99510a0a..088d0d2bdf 100644
--- a/tests/testament/tshould_not_work.nim
+++ b/tests/testament/tshould_not_work.nim
@@ -24,6 +24,8 @@ FAIL: tests/shouldfail/tnimout.nim
 Failure: reMsgsDiffer
 FAIL: tests/shouldfail/tnimoutfull.nim
 Failure: reMsgsDiffer
+FAIL: tests/shouldfail/tnotenoughretries.nim
+Failure: reExitcodesDiffer
 FAIL: tests/shouldfail/toutput.nim
 Failure: reOutputsDiffer
 FAIL: tests/shouldfail/toutputsub.nim
@@ -43,7 +45,7 @@ import stdtest/testutils
 
 proc main =
   const nim = getCurrentCompilerExe()
-  let testamentExe = "bin/testament"
+  let testamentExe = "testament/testament"
   let cmd = fmt"{testamentExe} --directory:testament --colors:off --backendLogging:off --nim:{nim} category shouldfail"
   let (outp, status) = execCmdEx(cmd)
   doAssert status == 1, $status
diff --git a/tests/types/ttopdowninference.nim b/tests/types/ttopdowninference.nim
index 765761e993..303effdf7b 100644
--- a/tests/types/ttopdowninference.nim
+++ b/tests/types/ttopdowninference.nim
@@ -331,3 +331,25 @@ block: # issue #24164, related regression
   template bar(x: untyped = nil) =
     foo(x)
   bar()
+
+block: # bug #24296
+  # Either changing the template to `proc`/`func` or using `$""`, not a string
+  # literal alone, allows any version of Nim 2.x to compile this.
+  template g(): string = ""
+
+  # Alternatively: don't retrieve the string through g(), but directly, also
+  # allows compilation across Nim 2.x versions.
+  const d: cstring = ""
+  const f: cstring = $""
+  const b = cstring g()
+  const m = cstring ""
+  const p = cstring $""
+
+  # But this does not compile across Nim 2.x/devel.
+  const c: cstring = g()
+  let e: cstring = g()
+
+block: # bug #24295
+  template g(_: int): string = ""
+  const c: cstring = 0.g()
+
diff --git a/tools/ci_generate.nim b/tools/ci_generate.nim
index 46bc39470f..a461be5915 100644
--- a/tools/ci_generate.nim
+++ b/tools/ci_generate.nim
@@ -42,9 +42,9 @@ triggers:
 
 proc genBuildExtras(echoRun, koch, nim: string): string =
   result = fmt"""
-{echoRun} {nim} c --noNimblePath --skipUserCfg --skipParentCfg --hints:off koch
-{echoRun} {koch} boot -d:release --skipUserCfg --skipParentCfg --hints:off
-{echoRun} {koch} tools --skipUserCfg --skipParentCfg --hints:off
+{echoRun}{nim} c --noNimblePath --skipUserCfg --skipParentCfg --hints:off koch
+{echoRun}{koch} boot -d:release --skipUserCfg --skipParentCfg --hints:off
+{echoRun}{koch} tools --skipUserCfg --skipParentCfg --hints:off
 """
 
 proc genWindowsScript(buildAll: bool): string =
@@ -95,7 +95,7 @@ set -e # exit on first error
 . ci/funs.sh
 nimBuildCsourcesIfNeeded "$@"
 
-{genBuildExtras("echo_run", "./koch", "bin/nim")}
+{genBuildExtras("echo_run ", "./koch", "bin/nim")}
 """
 
 proc main()=
diff --git a/tools/kochdocs.nim b/tools/kochdocs.nim
index 458e3f014f..9798a48e6a 100644
--- a/tools/kochdocs.nim
+++ b/tools/kochdocs.nim
@@ -198,11 +198,11 @@ proc getDocList(): seq[string] =
   # don't ignore these even though in lib/system (not include files)
   const goodSystem = """
 lib/system/nimscript.nim
-lib/system/assertions.nim
 lib/system/iterators.nim
 lib/system/exceptions.nim
 lib/system/dollars.nim
 lib/system/ctypes.nim
+lib/system/repr_v2.nim
 """.splitWhitespace()
 
   proc follow(a: PathEntry): bool =