Hold a strong reference to DebuggerController in detached worker threads#1086
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The 17 `Launch`/`Attach`/`Connect`/`Go`/`Step*`/`RunTo*`/`Restart`/`Detach`/ `Quit`/`Pause` methods each spawn a detached `std::thread` that runs the corresponding `*AndWait` work, capturing `this` by reference. Nothing keeps the controller alive for the duration of the detached call, so if the controller's refcount drops to zero before the worker exits (e.g. the user closes the tab), the worker dereferences a dangling pointer. Capture a `DbgRef<DebuggerController>` by value into each lambda so the controller stays alive until the worker thread finishes. Fixes #1083. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
This was referenced May 20, 2026
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Summary
DebuggerControllermethods that spawn a detached worker thread (Launch,Attach,Connect,Go,GoReverse,Step{Into,Over,Return}{,Reverse},RunTo{,Reverse},Restart,Detach,Quit,Pause) all capturedthisby reference, with nothing ensuring the refcounted controller stayed alive for the duration of the detached call.DbgRefwas dropped (e.g. the user closed the tab) before the worker finished, the worker would dereference a freedDebuggerController— that's the crash in Crash below DebuggerController::DetachAndWait #1083 (and the same shape as several other Sentry reports:RspConnector::SendRaw,DbgEngAdapter::ReadMemory, etc.).DbgRef<DebuggerController> self = this;and the lambda capturesselfby value, so the refcount reflects the running thread and the controller can't be destroyed under it.The constructor's
m_debuggerEventThread(line 41) is unchanged because it's stored as a member and joined explicitly in the destructor — already safe.Fixes #1083.
Test plan
ninja debuggercore)🤖 Generated with Claude Code