fix: use NonBlockingCall in ThreadedAsyncOperation to prevent SIGBUS on macOS#21624
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The JS callback destroyed `this` while BlockingCall was still on the worker thread's call stack. On macOS, the freed page is unmapped immediately → SIGBUS. Move `delete this` to after BlockingCall returns on the worker thread.
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dbanks12
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Mar 16, 2026
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Fixes SIGBUS crash on macOS in
ThreadedAsyncOperation(#21138).delete opwas inside theBlockingCallcallback, destroying the object whileBlockingCallwas still unwinding on the worker thread. macOS unmaps freed pages aggressively → SIGBUS. Linux keeps them mapped → silent use-after-free.Fix: move
delete thisto afterBlockingCallreturns on the worker thread.Full post mortem with diagrams