## Fix `globalSymbols` support on POSIX
### Summary
Fix `-d:globalSymbols` on POSIX platforms by defining `RTLD_GLOBAL`
alongside `RTLD_NOW` in `system/dyncalls.nim`.
On Linux and macOS, `RTLD_NOW` is defined locally in `dyncalls.nim`, but
`RTLD_GLOBAL` was not. As a result, enabling `-d:globalSymbols` could
fail because `RTLD_GLOBAL` was undeclared.
This change:
* defines `RTLD_GLOBAL` as `0x100` on Linux,
* defines `RTLD_GLOBAL` as `0x8` on macOS,
* imports `RTLD_GLOBAL` from `<dlfcn.h>` on other POSIX platforms.
These values are consistent with the existing POSIX constants already
used elsewhere in the Nim source tree.
### Motivation
`globalSymbols` is intended to load dynamic libraries with `RTLD_GLOBAL`
so that their exported symbols are available to subsequently loaded
shared libraries.
This is needed, for example, when a dynamically loaded library later
loads a plugin or provider that depends on symbols from the first
library.
Without this fix, `-d:globalSymbols` cannot be used reliably for that
purpose on POSIX systems.
### Testing
Tested on Linux with an AArch64 target.
A program using dynamically loaded OpenSSL libraries and a subsequently
loaded OpenSSL provider failed when the OpenSSL libraries were loaded
with the default local symbol visibility.
Using `RTLD_GLOBAL` made the same program work correctly.
After this change, building the original Nim program with:
```text
-d:globalSymbols
```
successfully loads the OpenSSL libraries with global symbol visibility,
and the provider-based TLS 1.2 and TLS 1.3 tests both pass.
The same behavior was also independently reproduced using direct
`dlopen()` / `dlsym()` calls:
```text
RTLD_LOCAL -> TLS 1.2 failed
RTLD_GLOBAL -> TLS 1.2 passed
```
Signed-off-by: Takeyoshi Kikuchi <kikuchi@centurysys.co.jp>
(cherry picked from commit 226cfff540)
`nimDecRefIsLast` always performed an atomic decrement. When the biased
count is already zero the destroying thread holds the only reference, so
there is nothing to adjudicate and the read-modify-write can be skipped.
Soundness: a counted reference can only be derived from the location
being destroyed -- which happens-before this destructor unless the
program races on that location -- or from another counted reference,
whose contribution is already in `rc` and therefore forces the slow
path. Observing zero proves no other thread holds a reference and that
none can appear. This relies on `--mm:atomicArc` having no collector;
ORC and YRC mutate `rc` from a participant that holds no counted
reference at all, so the fast path is deliberately not enabled for them.
The slow path keeps deciding on the value its own RMW returned. That is
what separates this from nim-lang/threading#45, where the "who frees"
role was decided from a separate load and the RMW result was discarded,
so the role could be dropped by every participant at once.
gcbench, -d:danger, median of 21 pinned runs:
--mm:arc (non-atomic RC) 0.1310
--mm:atomicArc 0.1742
--mm:atomicArc + this 0.1330
-23.7%, closing 95% of the gap to non-atomic reference counting. gcbench
builds its trees with `sink` parameters, so it performs almost no
incRefs and the whole atomicArc penalty is decRef traffic. The worst
case -- a decrement that always sees rc > 0, so the load never pays off
-- measures +1.1%.
`-d:nimNoAtomicArcFastPath` restores the previous code path.
(cherry picked from commit 5a0e4ff6b1)
## Summary
- nimpretty with non-default \--indent\ (e.g. 3 or 10) produced invalid
indentation in if/block/try expression regions because layouter kept the
original column when \keepIndents > 0\ and ignored \indWidth\.
- Rebase the column onto \indWidth\ using the relative offset from the
enclosing block baseline (\indentStack[^1]\).
## Root cause
\parser.nim\'s \
imprettyDontTouch\ template sets \keepIndents\ for if/block/try
expressions. layouter in the \keepIndents > 0\ branch used \ ok.indent\
(source column) directly as \indentLevel\ without scaling by \indWidth\,
so lines in these regions kept the original column and misaligned with
the rest of the file when \--indent\ differed from source indent width.
## Fix
\\\
im
em.indentLevel = em.indentStack.high * em.indWidth +
(tok.indent - em.indentStack[^1])
\\\
Keeps the relative offset from the enclosing block baseline but rebases
onto \indWidth\. At default \--indent:2\ the offset equals \indWidth\,
so output is unchanged (backwards compatible).
## Testing
- 12 custom cases x 3 indent values (2/3/10) = 36/36 pass
- nimpretty self-test suite 7/7 pass (no regression at default indent)
- 5 keepIndents scenarios (if/block/try expression continuation
alignment) that failed at indent:3/10 now pass
Fixes#20078.
(cherry picked from commit 1e82deb73d)
fixes#25942fixes#25938
After a successful match to a concrete static T, normalizes an empty
static container literal to the formal payload type before binding it.
This prevents `static[set[empty]]({})` from leaking into the
instantiated proc body.
(cherry picked from commit 234f01510f)
fixes#26045;
fixes#26046
The fix isolates compiler option state while semantically checking each
when nimvm branch.
compiler/semexprs.nim:2745 snapshots the option stack, compiler options,
diagnostics settings, and enabled features. It analyzes one branch and
restores that state in finally. Both the nimvm and else branches use
this function.
This prevents:
```nim
when nimvm:
{.push overflowChecks: off.}
```
from disabling overflow checks in following runtime code. It also means
a {.pop.} in the opposite branch correctly reports that it has no
corresponding {.push.}.
(cherry picked from commit f6651e6c70)
Fixes#26027.
Map the single-order compare-exchange failure ordering from `release` to
`relaxed` and from `acquire-release` to `acquire`. Apply the mapping to
the trivial and non-trivial strong and weak overloads, and correct the
explicit-order test cases.
Tested `tests/stdlib/concurrency/tatomics.nim` across C/C++, refc/orc,
and native/C++ atomics (8 combinations). Also verified the original GCC
16.1 assertion reproducer.
(cherry picked from commit 95557ad48c)
`distinctBase` results in typedesc, so `set[T.distinctBase]` received
`typedesc[range[...]]` as its element type, which `isOrdinalType`
rejects. Strip the wrapper in `semSet` before storing the element type
and checking ordinality.
Also add `tyFromExpr` to the deferred-check set so the error doesn't
fire prematurely inside generic bodies - same pattern already used by
`semArray`.
(cherry picked from commit 2d81149294)
`toStrLit()` uses `repr()` internally, which forwards quotes and messes
with dashes in the output. Let's use `newStrLitNode()` directly instead.
GitHub: fixes https://github.com/nim-lang/Nim/issues/26039
(cherry picked from commit 0021205854)
fixes#26010
Cursors do not own their values and therefore cannot transfer ownership
through move.
Reject move(cursor) during semantic analysis and share the
cursor-location check
between semantic analysis and destructor injection.
(cherry picked from commit 99a696e0c4)
Fixes#23615
## Root cause
The leak does not require async at all -- this minimal closure iterator
leaks the exception and its stacktrace seq under ARC/ORC:
```nim
iterator it(): int {.closure.} =
try:
yield 1 # try spanning a yield => closureiters transform
raise newException(ValueError, "x")
except ValueError: # typed except => generated `of` check
discard
yield 2
```
A bare `except:` does not leak; a *typed* `except` does:
1. `collectExceptState` in `compiler/closureiters.nim` generates the
except-branch type check as `of(getCurrentException(), T)`, using the
raw generic magic sym from `getSysMagic("of", mOf)`.
2. `injectdestructors` skips call arguments whose *formal* parameter
type is `isCompileTimeOnly`, and the raw generic `of` sym's formal
params are `tyGenericParam` so both arguments of the generated `of` call
are never processed.
3. `getCurrentException()` increfs `currException` via `=copy` into its
result. Since the arc pass never wraps that owned temp in a destroy
(`--expandArc` shows the condition left untouched, while a user-written
`if f() of ValueError` in the same iterator gets a `:tmpD` +
`=destroy`), the caught exception's refcount stays +1 forever.
Every `try: await x() except SomeError` in async code has this shape, so
each caught async exception leaked once.
## Fix
The state-machine wrapper already stores the active exception in the
`:curExc` env field before jumping to the except landing state, and
`currException == :curExc` on every path into that state. The generated
condition now references the env field via `ctx.newCurExcAccess()`
instead of calling `getCurrentException()` again -- no ownership
transfer, no temp to destroy, one fewer runtime call.
Note: the underlying `injectdestructors` behavior (skipping args of
calls whose formal params are raw `tyGenericParam`, e.g. from
`getSysMagic`) is a separate latent gap that could affect other
compiler-generated code; it is intentionally left untouched here.
## Valgrind, before and after
Exact code and command from the issue, on Linux (Valgrind 3.19):
```
nim c -d:danger --mm:orc --debugger:native --threads:off -d:useMalloc bug.nim
valgrind --leak-check=full --show-leak-kinds=all ./bug
```
Before (devel):
```
==14663== HEAP SUMMARY:
==14663== in use at exit: 136 bytes in 2 blocks
==14663== total heap usage: 22 allocs, 20 frees, 116,466 bytes allocated
==14663==
==14663== 56 bytes in 1 blocks are indirectly lost in loss record 1 of 2
==14663== at 0x488A1C4: realloc (vg_replace_malloc.c:1437)
==14663== by 0x10C663: prepareSeqAddUninit (seqs_v2.nim:212)
==14663== by 0x10CF6F: raiseExceptionEx (excpt.nim:538)
==14663== by 0x11661F: amain::amainX20X28AsyncX29_(Future<void>) (bug.nim:10)
==14663== ...
==14663==
==14663== 136 (80 direct, 56 indirect) bytes in 1 blocks are definitely lost in loss record 2 of 2
==14663== at 0x48850C8: malloc (vg_replace_malloc.c:381)
==14663== by 0x10C8E3: nimNewObj (arc.nim:122)
==14663== by 0x115403: err::errX20X28AsyncX29_(Future<void>) (asyncmacro.nim:274)
==14663== by 0x116027: err::errNimAsyncContinue(Future<void>, ClosureIt<void>) (asyncmacro.nim:44)
==14663== by 0x1163D3: bug::err (bug.nim:3)
==14663== ...
==14663==
==14663== LEAK SUMMARY:
==14663== definitely lost: 80 bytes in 1 blocks
==14663== indirectly lost: 56 bytes in 1 blocks
==14663== possibly lost: 0 bytes in 0 blocks
==14663== still reachable: 0 bytes in 0 blocks
==14663== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 0 from 0)
```
After (this PR):
```
==14675== HEAP SUMMARY:
==14675== in use at exit: 0 bytes in 0 blocks
==14675== total heap usage: 22 allocs, 22 frees, 116,466 bytes allocated
==14675==
==14675== All heap blocks were freed -- no leaks are possible
==14675==
==14675== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
```
## Testing
- New `tests/async/t23615.nim` (modeled on `t23212.nim`: `valgrind:
true` + alloc-stats assertion) covers both the pure closure-iterator
form and the async form from the issue, with the caught exception looped
50x so the leak blows well past the slack threshold. It passes with this
PR and fails against devel.
- Testament categories `async`, `arc`, `iter`, `exception` all pass with
the patched compiler (323 tests).
- Behavior is unchanged on a sanity program covering multi-branch
dispatch, `as e` binding, nested try, and re-raise across yields: output
is byte-identical to devel; the patched build just frees 2 more blocks
per caught exception.
(cherry picked from commit 8e8f8de1ab)
…pile time
fixes#26000
vm: preserve lvalues for mutations of broadcast array elements
Load in-place mutation targets through their address so mutations don't
operate on detached copies of broadcast defaults. This also preserves
nested lvalues and evaluates indexed destinations only once.
Cover sequence, string, and set mutations through direct, nested, field,
enum-indexed, and range-indexed array elements.
(cherry picked from commit 2915691515)
Fix proposed by GPT 5.6 Sol.
close#26016
Potentially close#22510
No concrete proof for the second one, though the described behavior
matches and the step count explains why it's so difficult to find a
repro.
(cherry picked from commit 3bb46d3217)
These functions are unused and never exposed publically - along with it,
get rid of `GC_Strategy` - although it's possible someone could use this
`enum` for their own code it seems unlikely.
(cherry picked from commit ddcaed7f70)
Fixes#25997
`executeNoHooksV3`'s `ideType` handler dereferences the target symbol's
type
without nil checks, so nimsuggest (v3/v4) dies with SIGSEGV on a `type`
query for any symbol without a usable type:
- a **void proc** — `s.sym.typ[0]` (the return-type slot) is nil, e.g.
"goto type definition" on the `add` in `s.add('x')`;
- a **module symbol** — `s.sym.typ` is nil, e.g. a `type` query on the
module name in an `import` statement.
Both are one editor action away for any user whose client maps
`textDocument/typeDefinition` to `type` (nimlangserver does), and the
crash
takes down the whole nimsuggest process. Root-caused from recurring
nimlangserver crash reports by replaying a live session log; reproduced
deterministically with a two-line file.
The fix guards the derefs and returns an empty result for symbols with
no
type, matching the existing "bad type" behavior. Two regression cases
are
appended to `nimsuggest/tests/tv3_typeDefinition.nim` (appended at the
end
so the existing `$1`–`$4` line-number expectations are untouched); both
crash with `SIGSEGV: Illegal storage access` before the fix and pass
after.
The existing `$3` generic case covers the guarded `elif` branch.
(cherry picked from commit 74cd4cbf3c)
fix#25976
Initialize tagEffects for proc types that declare .forbids but omit
.tags,
so they behave like explicit tags: [] during indirect-call effect
tracking.
Add a regression for the nested callback assignment case.
(cherry picked from commit 4b1444e728)
fixes#25886fixes#25883
See #25883
Tuples only hash leaves so if 2 tuples have the same flattened
representation they collide in the C codegen.
Fix by hashing the length as well to disambiguate nesting levels.
---------
Co-authored-by: ringabout <43030857+ringabout@users.noreply.github.com>
(cherry picked from commit e50fafc971)
I was updating nim to 2.2.10 in nixpkgs
https://github.com/NixOS/nixpkgs/pull/538469
and without this change the fail build, because add(string, cstring) is
not defined. I think it's caused by a change of position of the includes
in system, but with this it works fine.
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
(cherry picked from commit a58e07b336)
fix#25608
This pull request improves how the compiler handles warnings for
implicit range conversions, ensuring that only non-constant values
trigger downsizing warnings. It also adds new test cases to verify that
assignments and function calls involving compile-time constants do not
produce unnecessary warnings.
Improvements to range conversion warnings:
* Updated the logic in `compiler/sempass2.nim` to skip implicit range
conversion warnings for compile-time constants by checking if an
expression is constant with `getConstExpr`. Now, only non-constant
values will trigger the warning.
Testing enhancements:
* Added new test cases in `tests/range/timplicitrangedownsizing.nim` to
confirm that assignments and function calls with constant enum and
integer values do not trigger downsizing warnings.
(cherry picked from commit c70a4502d2)
Explicit `=sink` calls such as `Isolated[T].=sink` can delegate to a
field type like `float`, which has no attached sink op. In that case
`replaceHookMagic` leaves the builtin `mAsgn` call in place.
`genMagicExpr` did not lower that shape, which caused the regression.
Mapping `=sink` to `nkSinkAsgn` and other builtin assignment hooks to
`nkAsgn`.
(cherry picked from commit 985b1125b1)
The emscripten branch cast the descriptor address to the value type
EmscriptenMMapBlock instead of the pointer alias PEmscriptenMMapBlock,
so osAllocPages stored realSize/realPointer in a discarded local and
osDeallocPages reinterpreted the address integer as the descriptor
instead of dereferencing it -- calling munmap() with garbage that fails,
so freed pages are never returned. Freed huge chunks are also dropped
from the free list, leaking permanently. Affects wasm32 and wasm64.
Cast to PEmscriptenMMapBlock so both accesses go through memory.
(cherry picked from commit 8101c8d73b)
fixes#25945
When `@[]` appears inside a nested `if` expression that also contains
statements, the AST wraps it in `nkStmtListExpr` nodes. The empty
container's `tyEmpty` element type was never resolved to a concrete
type, causing the C codegen to ICE with "cannot map the empty seq type
to a C type".
Walk through nested statement-list/block expressions in
`fitNodePostMatch` to find the innermost value node and propagate the
formal type to empty containers.
(cherry picked from commit a0e44d7aca)
This PR implements `expandSymlink` on Windows with POSIX readlink
semantics: it expands exactly one hop and returns the stored link target
without resolving the full chain.
The main design question was whether Windows symlink expansion should be
built on path-finalization APIs such as `GetFinalPathNameByHandleW`, or
on direct reparse-point inspection. Current `expandSymlink` is a
single-hop "what target is stored in this link object?" operation and
most of other ways to resolve symlinks on Windows actually try to answer
the "final true file location" question in various slightly-incompatible
ways.
The full final-path resolution on Windows is substantially more complex
than readlink and is planned as a follow-up.
## Implementation choice
Implements Windows `expandSymlink` by:
- opening the path with `FILE_FLAG_OPEN_REPARSE_POINT`
- calling `DeviceIoControl(FSCTL_GET_REPARSE_POINT)`
- parsing the reparse payload for `IO_REPARSE_TAG_SYMLINK` and
`IO_REPARSE_TAG_MOUNT_POINT`
- decoding the UTF-16 slice referenced by the payload
- returning the stored target
This is the right primitive for the API:
- does not depend on whole-path finalization
- works for both symlinks and junctions
- matches the existing Linux behaviour
`widestrs` changes allow using WideCString views without temporary
allocations.
Windows prohibits symlink creation without admin rights, so,
unfortunately, the tests are conditionally skipped by default. Manually
running `testament` in an admin console is required.
## Behaviour:
- One hop only
- Relative symlink targets are returned unchanged
- Absolute Windows targets are converted from stored NT-style prefixes
to usable Win32 forms when applicable
- Non-links, malformed payloads, and unsupported reparse tags raise
`OSError`
## Future work
Path canonicalization, i.e. "final true file location". Which is, BTW,
different from `absolutePath`, which works on paths only and doesn't hit
the underlying FS. So this needs to be an API extension.
I'd like to follow-up with this when I sort through the docs, for now
you can resolve symlinks in a loop.
---------
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
(cherry picked from commit 00d8f66311)
fixes#25931
This fix addresses bug #25931 — a signature hash collision with
importc-aliased pointer/cstring types.
The problem: In compiler/sighashes.nim, the hashType procedure
canonicalizes types for signature hashing. Integral types
(tyInt..tyUInt64, etc.) were excluded from canonicalization so that
types like pid_t (an importc alias) keep their backend spelling. But
pointer and cstring types with importc annotations were not excluded —
meaning a type like:
type N {.importc: "const void *".} = pointer
...would be collapsed to just pointer in the signature hash, causing
collisions when N and pointer are both used in procedure types within
the same compilation unit.
The fix (compiler/sighashes.nim:193): Adds tyPointer and tyCstring to
the list of types that skip canonicalization, right alongside the
integral types. The comment is updated to clarify this applies to
"builtin scalar-ish / pointer-like types".
The test (tests/ccgbugs/tsighash_typename_regression.nim:33-42): Adds a
regression test exercising the exact scenario — an importc pointer alias
used in both an object field type and a proc parameter type.
(cherry picked from commit 056eeeae30)
fixes#25908
When an enum identifier is resolved as an `nkSymChoice`, one of the
candidates may come from a loop-local view and carry `tyVar` or
`tyLent`.
Enum disambiguation should compare the underlying enum type only.
Otherwise a pure-enum field can win incorrectly even though the intended
symbol is already present in the choice set.
Keep the `includePureEnum` lookup path for enum-typed expectations so
#23976 still works, but normalize `var`/`lent` only at the symchoice
selection point.
(cherry picked from commit 6eef0cc2d5)
closureiters.nim splits a stmt list at yield points, moving post-yield
code into a new state body. When that stmt list was inside a pragma
block like `{.cast(uncheckedAssign).}`, the new state's body was created
as a bare nkStmtList without the wrapper.
Fix: track the enclosing pragma block in the transform context, and wrap
newly-created state bodies in a copy of it when the split occurs inside
one. Added an explicit `nkPragmaBlock` case to
`transformClosureIteratorBody` that saves/restores `ctx.enclosingPragma`
around its body.
(cherry picked from commit f8e470eb57)
Fixes#19240.
The Manual's "Delegating bind statements" example didn't compile (module
B didn't import A, type `O` wasn't exported, and `x: T` couldn't bind to
`var O`), and once those were fixed it compiled *without* the `bind`
statement — so it didn't demonstrate delegating bind at all.
This replaces it with a minimal example that genuinely requires `bind
init`: `module main` imports A and B but not C, so `init` is not in
scope at the final instantiation of `genericA`; the open `mixin` symbol
fails to resolve without `bind init` forwarding it from module B.
Verified to fail without `bind` and compile with `bind` under Nim
2.2.10.
---
Disclosure: I work with Claude as a co-processor. I understand what I'm
submitting and I verified the example against the compiler myself. If
you prefer human-only contributions, just say so and I'll close without
friction.
(cherry picked from commit c292ab987b)
fixes #22122
The commit fixes a bug in Nim's effects checker where raise statements
with case/if expressions (commonly from template expansion) failed to
track exception types from individual branches.
Problem: addRaiseEffect only saw the outermost expression. When a
template like getTransportError(err) expanded to a case expression
raising 3 different exception types, the compiler only registered the
top-level call — missing the branch-level exceptions.
Fix (2 files):
- compiler/sempass2.nim: Added skipHiddenConv to strip implicit type
coercion nodes (nkHiddenStdConv/nkHiddenSubConv) that hide the control
flow structure. Added addRaiseEffectsFromExpr that recursively walks
into case/if/block/stmtlist expressions to find raise effects in each
branch body. Changed the nkRaiseStmt handler to use this new function.
- tests/effects/tcase_raises.nim: Test with templates that expand to
case expressions raising different exception types, verified via
{.raises: [].} pragma.
(cherry picked from commit 587f90a816)
fixes#18367fixes#21222
1. In vmdef.nim:304, newCtx now sets templInstCounter: new int when it
builds TCtx.
2. vm.nim:1490 — During VM execution of templates, c.templInstCounter is
passed to evalTemplate
3. evaltempl.nim:204 — instID: instID[] dereferences the ref int
4. With a nil templInstCounter, this would crash
5. The same initialization already exists on the semantic side in
sem.nim:787, so this change makes the VM path consistent with the rest
of the compiler.
(cherry picked from commit 67707a54b5)
fixes#25903fixes#25904
`nkExceptBranch` can have variable structure depending on the exception
types and it should handle the last node of the `nkExceptBranch`
(cherry picked from commit 0f751695e4)
