Stream: git-wasmtime

Topic: wasmtime / PR #11871 Document some known async pitfalls

Wasmtime GitHub notifications bot (Oct 15 2025 at 21:55):

alexcrichton requested dicej for a review on PR #11871.

Wasmtime GitHub notifications bot (Oct 15 2025 at 21:55):

alexcrichton opened PR #11871 from alexcrichton:doc-some-pitfalls to bytecodealliance:main:

• call_concurrent is more like a "spawn" operation within a store so it cannot be cancelled by dropping the returned future.
• call_concurrent cannot be cancelled today other than by dropping the whole store. This is the subject of #11833.
• call_concurrent cannot make progress outside of run_concurrent.
• run_concurrent does not properly implement "select" operations internally due to #11869 and #11870. This means that timeouts within run_concurrent will not work.

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Wasmtime GitHub notifications bot (Oct 15 2025 at 21:55):

alexcrichton requested wasmtime-core-reviewers for a review on PR #11871.

Wasmtime GitHub notifications bot (Oct 15 2025 at 22:29):

dicej submitted PR review.

Wasmtime GitHub notifications bot (Oct 15 2025 at 22:29):

dicej created PR review comment:

"is reentered" connotes recursion; maybe just say "is called again" here?

Wasmtime GitHub notifications bot (Oct 15 2025 at 22:29):

dicej created PR review comment:

A possibly clearer (or at least more precise) way to phrase this first sentence:

At this time there are certain situations in which the Future returned by the AsyncFnOnce passed to this function will not be polled for an extended period of time, despite one or more Waker::wake events having occurred for the task to which it belongs. This can manifest as the Future seeming to be "blocked" or "locked up", but is actually due to the Store being held by e.g. a blocking host function, preventing the Future from being polled.

Wasmtime GitHub notifications bot (Oct 16 2025 at 14:24):

alexcrichton updated PR #11871.

Wasmtime GitHub notifications bot (Oct 16 2025 at 14:24):

alexcrichton has enabled auto merge for PR #11871.

Wasmtime GitHub notifications bot (Oct 16 2025 at 15:15):

alexcrichton merged PR #11871.

Last updated: Jan 10 2026 at 02:36 UTC