Fix current instance count on failure during component instantiation#13048
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alexcrichton wants to merge 1 commit intobytecodealliance:mainfrom
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Fix current instance count on failure during component instantiation#13048alexcrichton wants to merge 1 commit intobytecodealliance:mainfrom
alexcrichton wants to merge 1 commit intobytecodealliance:mainfrom
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This commit fixes an issue during component instantiation where if instantiation failed during creation of the `Instantiator` due to OOM or if the `async` future was dropped the concurrent instance count in the pooling allocator would get corrupted (off-by-one). The fix here is to switch a `map_err` with a manual decrement to using a value that has a destructor to ensure that it handles both of these cases.
fitzgen
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Apr 10, 2026
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| // Everything has passed, don't decrement the instance count and let the | ||
| // destructor for the `Store` handle that at this point. | ||
| decrement.enabled = false; |
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Instead of an enabled flag, maybe mem::forget(decrement) here? LLVM can probably keep enabled from being materialized at runtime, but the forget pattern seems no worse for ergonomics and guarantees that we won't need a bool flag at runtime.
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This commit fixes an issue during component instantiation where if instantiation failed during creation of the
Instantiatordue to OOM or if theasyncfuture was dropped the concurrent instance count in the pooling allocator would get corrupted (off-by-one). The fix here is to switch amap_errwith a manual decrement to using a value that has adestructor to ensure that it handles both of these cases.