240707 2022-05-20 00:35:02 -0700 REGRESSION(250571@main)[Win] "Exception thrown: read access violation. " in WTF::Thread::ThreadHolder::~ThreadHolder() 2022-06-01 07:34:58 -0700 1 1 1 Unclassified WebKit Web Template Framework WebKit Nightly Build Unspecified Unspecified RESOLVED FIXED P2 Normal --- 1 fujii ysuzuki pvollan webkit-bug-importer oldest_to_newest 1870650 0 fujii 2022-05-20 00:35:02 -0700 REGRESSION(250571@main)[WinCairo] "Exception thrown: read access violation. " in WTF::Thread::ThreadHolder::~ThreadHolder() If I run WinCairo WK1 and WK2 with debugger attached, the following exception is thrown by browsing some sites. Exception thrown: read access violation. **_Val** was 0x188. Callstack WTF.dll!std::exchange<WTF::Thread::ClientData *,std::nullptr_t &>(WTF::Thread::ClientData * & _Val, void * & _New_val) Line 616 C++ WTF.dll!WTF::RawPtrTraits<WTF::Thread::ClientData>::exchange<std::nullptr_t>(WTF::Thread::ClientData * & ptr, void * && newValue) Line 41 C++ WTF.dll!WTF::RefPtr<WTF::Thread::ClientData,WTF::RawPtrTraits<WTF::Thread::ClientData>,WTF::DefaultRefDerefTraits<WTF::Thread::ClientData>>::operator=(void * __formal) Line 163 C++ WTF.dll!WTF::Thread::ThreadHolder::~ThreadHolder() Line 273 C++ WTF.dll!WTF::`dynamic atexit destructor for 's_threadHolder''() C++ WTF.dll!__dyn_tls_dtor(void * __formal, const unsigned long dwReason, void * __formal) Line 119 C++ ntdll.dll!LdrpCallInitRoutine() Unknown ntdll.dll!LdrpCallTlsInitializers() Unknown ntdll.dll!LdrShutdownThread() Unknown ntdll.dll!RtlExitUserThread() Unknown KernelBase.dll!FreeLibraryAndExitThread() Unknown ucrtbase.dll!common_end_thread() Unknown ucrtbase.dll!thread_start<unsigned int (__cdecl*)(void *),1>() Unknown kernel32.dll!BaseThreadInitThunk() Unknown ntdll.dll!RtlUserThreadStart() Unknown 1870651 1 fujii 2022-05-20 00:37:18 -0700 Since 250571@main (Bug 240116). 1870652 2 fujii 2022-05-20 00:54:12 -0700 I tested with AppleWin Release 250571@main, and confirmed it also has this bug. https://build.webkit.org/#/builders/67/builds/11801 https://s3-us-west-2.amazonaws.com/archives.webkit.org/win-x86_64-release/250571@main.zip I need to run MiniBrowser.exe with debugger atttached > devenv -debugexe MiniBrowser.exe If I run MiniBrowser.exe without debugger, it runs almost no problem. The mouse cursor was indicating busy. Task Manager is showing Windows Problem Reporting process is spawn. 1870664 3 ysuzuki 2022-05-20 01:56:27 -0700 Pull request: https://github.com/WebKit/WebKit/pull/823 1870673 4 ews-feeder 2022-05-20 02:17:40 -0700 Committed r294539 (250794@main): <https://commits.webkit.org/250794@main> Reviewed commits have been landed. Closing PR #823 and removing active labels.