rust: Fix receiving async events in busy yield loops#1439
Merged
alexcrichton merged 1 commit intobytecodealliance:mainfrom Nov 27, 2025
Merged
rust: Fix receiving async events in busy yield loops#1439alexcrichton merged 1 commit intobytecodealliance:mainfrom
alexcrichton merged 1 commit intobytecodealliance:mainfrom
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This commit fixes an issue with the rust async support where when a yield-loop was detected it suspended with `CALLBACK_CODE_YIELD` which meant that it wasn't possible to deliver async events for other async operations in progress. The fix is to instead return `CALLBACK_CODE_POLL` with the waitable-set that has all the waitables inside of it. This enables delivery of async events from that set to ensure that if the yielding task is waiting on something else that it gets delivered. This also refactors a few things here and there, such as `CALLBACK_CODE_*`, to be less error prone. Support was added for composing 3+ components with `wasm-compose` since `wac` doesn't yet use the same `wasm-tools`.
dicej
approved these changes
Nov 27, 2025
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This commit fixes an issue with the rust async support where when a yield-loop was detected it suspended with
CALLBACK_CODE_YIELDwhich meant that it wasn't possible to deliver async events for other async operations in progress. The fix is to instead returnCALLBACK_CODE_POLLwith the waitable-set that has all the waitables inside of it. This enables delivery of async events from that set to ensure that if the yielding task is waiting on something else that it gets delivered.This also refactors a few things here and there, such as
CALLBACK_CODE_*, to be less error prone. Support was added for composing 3+ components withwasm-composesincewacdoesn't yet use the samewasm-tools.