Stream: git-wasmtime

Topic: wasmtime / PR #14126 Run linker callback finalizers on in...

Wasmtime GitHub notifications bot (Aug 12 2026 at 15:44):

grandpig opened PR #14126 from grandpig:fix-linker-callback-finalizers to bytecodealliance:main:

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Follow-up to bytecodealliance/wasmtime-go#293.

When one of the linker function APIs receives an invalid UTF-8 module or function name, to_str! returns an error before the Rust callback closure is constructed.

The closure owns the C-provided data and finalizer through ForeignData.

Constructing it after parsing the names therefore means that the finalizer is not called when name parsing fails.

Move callback construction before UTF-8 validation in:

• wasmtime_linker_define_func
• wasmtime_linker_define_func_unchecked
• wasmtime_linker_define_async_func

This transfers ownership of data to ForeignData before any fallible name parsing. If parsing fails, normal Rust drop behavior invokes the finalizer.

Regression tests verify this behavior for the checked, unchecked, and async linker function APIs.

Testing

• C API test suite: 137/137 passed
• cargo fmt --all -- --check
• clang-format dry run on the modified C++ test files
  

Wasmtime GitHub notifications bot (Aug 12 2026 at 15:44):

grandpig requested dicej for a review on PR #14126.

Wasmtime GitHub notifications bot (Aug 12 2026 at 15:44):

grandpig requested wasmtime-core-reviewers for a review on PR #14126.

Wasmtime GitHub notifications bot (Aug 12 2026 at 16:01):

:thumbs_up: dicej submitted PR review:

Thanks!

Wasmtime GitHub notifications bot (Aug 12 2026 at 16:01):

dicej has enabled auto merge for PR #14126.

Wasmtime GitHub notifications bot (Aug 12 2026 at 16:02):

dicej added PR #14126 Run linker callback finalizers on invalid names to the merge queue.

Wasmtime GitHub notifications bot (Aug 12 2026 at 16:29):

:check: dicej merged PR #14126.

Wasmtime GitHub notifications bot (Aug 12 2026 at 16:29):

dicej removed PR #14126 Run linker callback finalizers on invalid names from the merge queue.

Last updated: Aug 30 2026 at 09:07 UTC