🍒 [Concurrency] prevent races in task cancellation #38425
Merged
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Explanation: The way we triggered cancellation handlers on an already cancelled task was racy and may cause a handler not being triggered and potentially leaving resources never cleaned up. The new impl moves the checking in the right spot so we always trigger properly.
Reviewer: @rjmccall (reviewed original PR) @DougGregor
Radar/SR Issue: rdar://78177513
Risk: Small.
Testing: PR testing and CI on main.
Original PR: #38404