Wasmtime GitHub notifications bot (Oct 06 2026 at 18:20): Wasmtime GitHub notifications bot (Oct 06 2026 at 18:20):alexcrichton opened PR #14580 from alexcrichton:track-more-borrows to bytecodealliance:main:
Since resources were originally implemented in Wasmtime it's only ever tracked lends of
ownhandles. This was all that was necessary in a fully synchronous world, but with async no in the picture this is no longer sufficient. Notably lends of borrows need to be tracked due to the nature of async functions. The spec has always tracked lends of everything, and it's just Wasmtime's historical optimization that's no longer applicable.This is a behavior change for guests, but guests which now run into a trap were already likely running into odd behavior. Guest tables could get corrupt in the face of async with mismatched lends and such. This could cause spurious traps or crashes within the guest itself, but this never results in host-side crashing behavior.
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Wasmtime GitHub notifications bot (Oct 06 2026 at 18:20):alexcrichton requested pchickey for a review on PR #14580.
Wasmtime GitHub notifications bot (Oct 06 2026 at 18:20):alexcrichton requested wasmtime-core-reviewers for a review on PR #14580.
Wasmtime GitHub notifications bot (Oct 06 2026 at 18:25)::thumbs_up: pchickey submitted PR review.
Wasmtime GitHub notifications bot (Oct 06 2026 at 18:26):alexcrichton has enabled auto merge for PR #14580.
Wasmtime GitHub notifications bot (Oct 06 2026 at 18:31):alexcrichton added PR #14580 Track lends of borrows in the face of async to the merge queue.
Wasmtime GitHub notifications bot (Oct 06 2026 at 18:53):github-merge-queue[bot] removed PR #14580 Track lends of borrows in the face of async from the merge queue.
Wasmtime GitHub notifications bot (Oct 06 2026 at 18:54):alexcrichton added PR #14580 Track lends of borrows in the face of async to the merge queue.
Wasmtime GitHub notifications bot (Oct 06 2026 at 19:17)::check: alexcrichton merged PR #14580.
Wasmtime GitHub notifications bot (Oct 06 2026 at 19:17):alexcrichton removed PR #14580 Track lends of borrows in the face of async from the merge queue.
Last updated: Oct 11 2026 at 04:10 UTC