Wasmtime GitHub notifications bot (Oct 14 2026 at 22:09): Wasmtime GitHub notifications bot (Oct 14 2026 at 22:09):alexcrichton opened PR #14757 from alexcrichton:fix-pulley-small-stack to bytecodealliance:main:
This commit fixes a possible panic that can happen when Pulley generates a trap where the stack is almost full or very small. The specific issue here is that the entry trampoline for Pulley can fail, unlike native platforms, because it's interpreted and has stack checks, unlike native platforms. If this entry trampoline fails then the backtracing implementation panics on an inconsistent state because an activation is expected but was never fully set up.
The fix in this commit is to handle this case when Pulley traps and skip getting a backtrace of the top-most activation. This is done with some light refactoring to plumb some
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Wasmtime GitHub notifications bot (Oct 14 2026 at 22:09):alexcrichton requested dicej for a review on PR #14757.
Wasmtime GitHub notifications bot (Oct 14 2026 at 22:09):alexcrichton requested wasmtime-core-reviewers for a review on PR #14757.
Wasmtime GitHub notifications bot (Oct 14 2026 at 22:09):alexcrichton requested fitzgen for a review on PR #14757.
Wasmtime GitHub notifications bot (Oct 14 2026 at 22:09):alexcrichton requested wasmtime-default-reviewers for a review on PR #14757.
Wasmtime GitHub notifications bot (Oct 15 2026 at 01:07):github-actions[bot] added the label pulley on PR #14757.
Wasmtime GitHub notifications bot (Oct 15 2026 at 01:07):github-actions[bot] added the label wasmtime:api on PR #14757.
Wasmtime GitHub notifications bot (Oct 15 2026 at 01:08):github-actions[bot] commented on PR #14757:
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Wasmtime GitHub notifications bot (Oct 15 2026 at 20:01)::thumbs_up: fitzgen submitted PR review.
Wasmtime GitHub notifications bot (Oct 15 2026 at 20:02):fitzgen added PR #14757 Fix a possible panic with small stacks and Pulley to the merge queue.
Wasmtime GitHub notifications bot (Oct 15 2026 at 21:31)::check: fitzgen merged PR #14757.
Wasmtime GitHub notifications bot (Oct 15 2026 at 21:31):fitzgen removed PR #14757 Fix a possible panic with small stacks and Pulley from the merge queue.
Last updated: Oct 31 2026 at 23:03 UTC