Wasmtime GitHub notifications bot (Mar 31 2026 at 13:40): Wasmtime GitHub notifications bot (Mar 31 2026 at 13:40):alexcrichton opened PR #12909 from alexcrichton:winch-memory-atomic-overflow to bytecodealliance:main:
This commit fixes a spec-compliance issue with
memory.atomic.*instructions using the Winch compiler. Specifically Winch previously added the dynamic offset to the static offset when calculating the effective address of the operation, but this addition was allowed to overflow. This meant that an operation which should trap would continue instead. The fix here is to use checked arithmetic at runtime to ensure that the address computation does not overflow.<!--
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Wasmtime GitHub notifications bot (Mar 31 2026 at 13:40):alexcrichton requested fitzgen for a review on PR #12909.
Wasmtime GitHub notifications bot (Mar 31 2026 at 13:40):alexcrichton requested wasmtime-compiler-reviewers for a review on PR #12909.
Wasmtime GitHub notifications bot (Mar 31 2026 at 13:40):alexcrichton requested wasmtime-core-reviewers for a review on PR #12909.
Wasmtime GitHub notifications bot (Mar 31 2026 at 13:56):alexcrichton updated PR #12909.
Wasmtime GitHub notifications bot (Mar 31 2026 at 17:03):github-actions[bot] added the label winch on PR #12909.
Wasmtime GitHub notifications bot (Mar 31 2026 at 17:04):github-actions[bot] commented on PR #12909:
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Wasmtime GitHub notifications bot (Mar 31 2026 at 18:25):saulecabrera submitted PR review:
Thanks!
Wasmtime GitHub notifications bot (Mar 31 2026 at 18:26):saulecabrera added PR #12909 winch: Fix memory.atomic.* with overflowing offsets to the merge queue.
Wasmtime GitHub notifications bot (Mar 31 2026 at 18:57):saulecabrera merged PR #12909.
Wasmtime GitHub notifications bot (Mar 31 2026 at 18:57):saulecabrera removed PR #12909 winch: Fix memory.atomic.* with overflowing offsets from the merge queue.
Last updated: Apr 12 2026 at 23:10 UTC