Wasmtime GitHub notifications bot (Oct 14 2026 at 20:30): Wasmtime GitHub notifications bot (Oct 14 2026 at 20:30):alexcrichton opened PR #14754 from alexcrichton:fix-eager-bounds-check to bytecodealliance:main:
This commit fixes a too-eager bounds-check for linear memories when they're imported, runtime configuration says memories cannot move, and the minimum size of the memory exceeds the runtime-configured default memory reservation. Imported memories are allowed to be larger than the declared minimum, and the default memory reservation is just a guideline and doesn't prevent memories being created larger than that. Effectively a special-case in bounds-checking just needed and extra clause to ignore imported linear memories because the special-case was inapplicable.
This fixes memory accesses that previously trapped to correctly fall back to a more general bounds check meaning that incorrect traps now succeed as they're supposed to.
Closes #14587
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Wasmtime GitHub notifications bot (Oct 14 2026 at 20:31):alexcrichton requested fitzgen for a review on PR #14754.
Wasmtime GitHub notifications bot (Oct 14 2026 at 20:31):alexcrichton requested wasmtime-compiler-reviewers for a review on PR #14754.
Wasmtime GitHub notifications bot (Oct 14 2026 at 20:31):alexcrichton requested wasmtime-core-reviewers for a review on PR #14754.
Wasmtime GitHub notifications bot (Oct 15 2026 at 19:57)::thumbs_up: fitzgen submitted PR review:
Good catch!
Wasmtime GitHub notifications bot (Oct 15 2026 at 19:57):fitzgen added PR #14754 Fix a bounds check for imported memories to the merge queue.
Wasmtime GitHub notifications bot (Oct 15 2026 at 20:19)::check: fitzgen merged PR #14754.
Wasmtime GitHub notifications bot (Oct 15 2026 at 20:19):fitzgen removed PR #14754 Fix a bounds check for imported memories from the merge queue.
Last updated: Oct 31 2026 at 23:03 UTC