fix: move Release and delete out of BlockingCall callback to prevent SIGBUS on macOS#21629
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fix: move Release and delete out of BlockingCall callback to prevent SIGBUS on macOS#21629
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This diff is large (needs rebase?), but the change to async_op.hpp lgtm
…SIGBUS on macOS Release() and delete were called inside the BlockingCall callback, which runs on the JS thread while BlockingCall is still blocked on the worker thread. Release() drops the TSFN refcount to 0, tearing down internal state that BlockingCall needs to unwind. delete destroys the TSFN member entirely. Both cause use-after-free when BlockingCall returns on the worker thread. macOS magazine malloc unmaps freed pages aggressively → SIGBUS. Fix: move both Release() and delete to after BlockingCall returns on the worker thread, where they can execute safely.
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Fixes SIGBUS crash on macOS in
ThreadedAsyncOperation(#21138). Also targeting next via #21625.Release()anddelete opwere inside theBlockingCallcallback, which runs on the JS thread whileBlockingCallis still blocked on the worker thread.Release()tears down TSFN internals (mutex/condvar) thatBlockingCallneeds to unwind, anddeletedestroys the member entirely. macOS unmaps freed pages aggressively → SIGBUS. Linux → silent use-after-free / segfault.Fix: move both
Release()anddelete thisto afterBlockingCallreturns on the worker thread.Full post mortem with diagrams