labath added a comment. In D77295#1995077 <https://reviews.llvm.org/D77295#1995077>, @JDevlieghere wrote:
> Hi Pavel, > > After this landed I started seeing a bunch of reproducers fail with > `SIGPIPE`. I ignored the signal and added a check for `EPIPE` to the > `::write` call in `PipePosix.cpp`. Below is the thread state: > > * thread #1, queue = 'com.apple.main-thread', stop reason = signal SIGPIPE > * frame #0: 0x00007fff6876c55e libsystem_kernel.dylib`__ulock_wait + 10 > frame #1: 0x00007fff6882f5c2 libsystem_pthread.dylib`_pthread_join + 347 > frame #2: 0x000000010115ef62 > liblldb.11.0.0git.dylib`lldb_private::HostThreadPosix::Join(this=0x000000011e7ca490, > result=0x00007ffeefbfe290) at HostThreadPosix.cpp:28:15 > frame #3: 0x000000010110b64f > liblldb.11.0.0git.dylib`lldb_private::HostThread::Join(this=0x000000011e9f09a0, > result=0x00007ffeefbfe290) at HostThread.cpp:21:27 > frame #4: 0x00000001012ea5ba > liblldb.11.0.0git.dylib`lldb_private::Process::ControlPrivateStateThread(this=0x000000011e9f0818, > signal=1) at Process.cpp:3642:30 > frame #5: 0x00000001012dbc81 > liblldb.11.0.0git.dylib`lldb_private::Process::StopPrivateStateThread(this=0x000000011e9f0818) > at Process.cpp:3593:5 > frame #6: 0x00000001012dc514 > liblldb.11.0.0git.dylib`lldb_private::Process::Destroy(this=0x000000011e9f0818, > force_kill=true) at Process.cpp:3317:7 > frame #7: 0x0000000100981cc1 > liblldb.11.0.0git.dylib`lldb::SBProcess::Kill(this=0x000000011e767de0) at > SBProcess.cpp:662:35 > > * thread #2 > * frame #0: 0x00007fff6876c4ce libsystem_kernel.dylib`__workq_kernreturn > + 10 > frame #1: 0x00007fff6882aaa1 libsystem_pthread.dylib`_pthread_wqthread > + 390 > frame #2: 0x00007fff68829b77 libsystem_pthread.dylib`start_wqthread + 15 > > * thread #3, name = '<lldb.process.internal-state(pid=47347)>' > * frame #0: 0x00007fff6876c55e libsystem_kernel.dylib`__ulock_wait + 10 > frame #1: 0x00007fff6882f5c2 libsystem_pthread.dylib`_pthread_join + 347 > frame #2: 0x000000010115ef62 > liblldb.11.0.0git.dylib`lldb_private::HostThreadPosix::Join(this=0x000000011e7ca510, > result=0x0000000000000000) at HostThreadPosix.cpp:28:15 > frame #3: 0x000000010110b64f > liblldb.11.0.0git.dylib`lldb_private::HostThread::Join(this=0x000000011e9f0e28, > result=0x0000000000000000) at HostThread.cpp:21:27 > frame #4: 0x0000000100f46f4e > liblldb.11.0.0git.dylib`lldb_private::Communication::StopReadThread(this=0x000000011e9f0de8, > error_ptr=0x0000000000000000) at Communication.cpp:239:32 > frame #5: 0x00000001012e9d95 > liblldb.11.0.0git.dylib`lldb_private::Process::ShouldBroadcastEvent(this=0x000000011e9f0818, > event_ptr=0x000000011e76aa40) at Process.cpp:3390:27 > frame #6: 0x00000001012e5e4f > liblldb.11.0.0git.dylib`lldb_private::Process::HandlePrivateEvent(this=0x000000011e9f0818, > event_sp=std::__1::shared_ptr<lldb_private::Event>::element_type @ > 0x000000011e76aa40 strong=2 weak=1) at Process.cpp:3697:33 > frame #7: 0x00000001012eb147 > liblldb.11.0.0git.dylib`lldb_private::Process::RunPrivateStateThread(this=0x000000011e9f0818, > is_secondary_thread=false) at Process.cpp:3891:7 > frame #8: 0x00000001012ea2fa > liblldb.11.0.0git.dylib`lldb_private::Process::PrivateStateThread(arg=0x000000011e7c9a60) > at Process.cpp:3789:25 > frame #9: 0x000000010110b45b > liblldb.11.0.0git.dylib`lldb_private::HostNativeThreadBase::ThreadCreateTrampoline(arg=0x000000011e7ca4e0) > at HostNativeThreadBase.cpp:68:10 > frame #10: 0x000000010726ab83 > liblldb.11.0.0git.dylib`lldb_private::HostThreadMacOSX::ThreadCreateTrampoline(arg=0x000000011e7ca4e0) > at HostThreadMacOSX.mm:68:10 > > * thread #4, name = '<lldb.comm.process.stdio>', stop reason = breakpoint > 1.1 > * frame #0: 0x000000010116071a > liblldb.11.0.0git.dylib`lldb_private::PipePosix::Write(this=0x000000011e7ca2b0, > buf=43698118819080247, size=1, bytes_written=0x00007000076908b8) at > PipePosix.cpp:312:7 > frame #1: 0x0000000101156d15 > liblldb.11.0.0git.dylib`lldb_private::ConnectionFileDescriptor::Disconnect(this=0x000000011e7ca210, > error_ptr=0x0000000000000000) at ConnectionFileDescriptorPosix.cpp:321:30 > frame #2: 0x0000000100f454e6 > liblldb.11.0.0git.dylib`lldb_private::Communication::Disconnect(this=0x000000011e9f0de8, > error_ptr=0x0000000000000000) at Communication.cpp:98:46 > frame #3: 0x0000000100f46d4e > liblldb.11.0.0git.dylib`lldb_private::Communication::ReadThread(p=0x000000011e9f0de8) > at Communication.cpp:377:13 > frame #4: 0x000000010110b45b > liblldb.11.0.0git.dylib`lldb_private::HostNativeThreadBase::ThreadCreateTrampoline(arg=0x000000011e7ca4e0) > at HostNativeThreadBase.cpp:68:10 > frame #5: 0x000000010726ab83 > liblldb.11.0.0git.dylib`lldb_private::HostThreadMacOSX::ThreadCreateTrampoline(arg=0x000000011e7ca4e0) > at HostThreadMacOSX.mm:68:10 > frame #6: 0x00007fff6882e109 libsystem_pthread.dylib`_pthread_start + > 148 > frame #7: 0x00007fff68829b8b libsystem_pthread.dylib`thread_start + 15 > > > Any chance you might know what's going on here? Hm... this probably didn't introduce the bug, but I can certainly see how it could cause an existing issue to start to appear more often. I think I have an idea for what could be problem here -- a race between the Disconnect call in `Communication::ReadThread` and the one in `Process::ShouldBroadcastEvent`. Can you check if swapping the order of these two lines in `Process::ShouldBroadcastEvent`: m_stdio_communication.Disconnect(); m_stdio_communication.StopReadThread(); makes the problem go away? Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D77295/new/ https://reviews.llvm.org/D77295 _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
