#162: ThreadChannel worker parked on recv() no longer hangs shutdown#167
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…l lock) The previous commit used a process-wide registry that the main thread iterated at quiesce to close every channel — one thread reaching into all threads' channels, behind a global mutex. Replace it with a per-thread registry in ASYNC_G: a channel created on a thread is registered there (holding a ref), and each thread closes the channels it created at its own engine_shutdown (before REACTOR_SHUTDOWN waits for child threads). No cross-thread access, no lock; the registry ref keeps a channel alive until its owner closes it. Re-proved: orphan_recv chaos sweep 150/150 (5 worker counts x random:1..30) on ASAN+async-fuzz, no hang/leak/UAF. Claude-Session: https://claude.ai/code/session_01NMdPEuD85qzTjv2N4ihTQU
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EdmondDantes
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A worker spawned via
Async\spawn_thread()and parked onThreadChannel::recv()kept the whole process alive when the owning side finished without
close().Fix (two parts):
while a coroutine actually
awaits the thread, so a non-awaited worker nolonger pins the parent, which reaches shutdown.
ThreadChannels it created and closes them at its ownengine_shutdown, so aworker parked on a channel whose owner finished wakes and exits. Thread-local,
no global lock; works for fan-out (any number of workers).
Tests:
thread_channel/042–044(recv / producer-coroutine / fan-out) + chaosfuzzy-tests/thread_channel/orphan_recv.featureproven 150/150 underrandom scheduler + ASAN (no hang/leak/UAF). Full thread/channel/coroutine/scope
suites green.