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Underspecification of disallowing waits on the main thread

Open Beginner friendly
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Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
68/100
Issue type
Documentation
Clarity
Mostly clear
Activity status
Quiet
Tech stack
javascript, wasm
Domain
documentation

Research direction

Start by reading the core spec and JS API spec sections covering waits, then compare their wording with the overview and the example comment about blocking on the main thread. Document that executing a wait on the main browser thread always traps, consistently with JavaScript Atomics.wait, whether or not suspension would occur.

Written by the indexing model from the issue text.

Description

I could not find anywhere in the core spec or JS API spec that says that waiting on the main browser thread traps. Even the overview does not directly address this except for a code comment in an example saying, Blocking on the main thread is not allowed, so we can't call lockMutex.

For consistency with Atomics.wait in JS, the expected behavior is that executing the wait always traps on the main thread, whether or not the thread would actually have been suspended.

Dominant language
WebAssembly
Stars
767
Forks
54
PR merge metrics
No merged PRs in 30d

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