Race condition in resume_foreground(DispatcherQueue) #378
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It's possible for the lambda to run before control returns to the caller of TryEnqueue. This led to async_suspend accessing m_queued after it has already been destroyed by the lambda. We make the lambda responsible for setting m_queued prior to resuming the coroutine. The lambda can infer that the task was queued by the fact that the lambda is running at all! If the enqueue fails, then m_queued remains at its initial value of false.
kennykerr
approved these changes
Oct 11, 2019
jlaanstra
approved these changes
Oct 11, 2019
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This fixes the problem of async_suspend accessing member variables after calling TryEnqueue.
It's possible for the lambda to run before control returns to the caller of TryEnqueue. This led to async_suspend accessing m_queued after it has already been destroyed by the lambda.
We make the lambda responsible for setting m_queued prior to resuming the coroutine. The lambda can infer that the task was queued by the fact that the lambda is running at all!
If the enqueue fails, then m_queued remains at its initial value of false.
This fixes #370