Debugging: fix panic in align_atomic_addr when guest-debug is enabled.#12815
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alexcrichton merged 1 commit intobytecodealliance:mainfrom Mar 21, 2026
Merged
Debugging: fix panic in align_atomic_addr when guest-debug is enabled.#12815alexcrichton merged 1 commit intobytecodealliance:mainfrom
alexcrichton merged 1 commit intobytecodealliance:mainfrom
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We have an invariant that the `stack_shape` and `stack` stacks are the same length whenever we emit debug tags. The invariant is temporarily broken when any result is pushed (the value stack becomes longer) but then restored between each instruction. Now that traps take debug tags too, we have to be careful to maintain the invariant. Usually no new results are pushed before checking for trap-conditions. However `align_atomic_addr` popped then re-pushed a value on the value stack before a trap check; this could cause the invariant to be violated and hence lead to a panic. This PR instead uses the `peek1` helper to maintain the shape stack entry. Fixes bytecodealliance#12808.
alexcrichton
approved these changes
Mar 21, 2026
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We have an invariant that the
stack_shapeandstackstacks are the same length whenever we emit debug tags. The invariant is temporarily broken when any result is pushed (the value stack becomes longer) but then restored between each instruction.Now that traps take debug tags too, we have to be careful to maintain the invariant. Usually no new results are pushed before checking for trap-conditions. However
align_atomic_addrpopped then re-pushed a value on the value stack before a trap check; this could cause the invariant to be violated and hence lead to a panic.This PR instead uses the
peek1helper to maintain the shape stack entry.Fixes #12808.