diff options
| author | Thiago Macieira <thiago.macieira@intel.com> | 2018-04-03 11:36:44 -0700 |
|---|---|---|
| committer | Thiago Macieira <thiago.macieira@intel.com> | 2018-05-02 21:06:32 +0000 |
| commit | f4394c86b68050c37ef6e56a7c30c50870875bcd (patch) | |
| tree | 667e6f3d6722cd3b4169981d71b8080bb1548cda /src/corelib | |
| parent | f240efaa353d9c2fea64a1b331fc2b5e5dcc5c47 (diff) | |
qFatal: Prevent deadlocks on Windows
We began using abort() on 25d6f312ac5b42a6bbca4d1c3c06742d97283e14
(5.8), which improved since we stopped using exit() with MSVC. However,
abort() with MinGW and on debug-mode MSVC's CRT calls _exit(), which
attempts to cleanly unload the DLLs, which in turn may run global
destructors.
[ChangeLog][QtCore][Important behavior changes] qFatal() no longer uses
std::abort() on Windows, as there are circumstances where global
destructors are still run after that call, leading to possible
deadlocks.
Task-number: QTBUG-34460
Change-Id: I2bec439d0e9841f58c7ffffd152200e45f1df982
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
Reviewed-by: Kai Koehne <kai.koehne@qt.io>
Diffstat (limited to 'src/corelib')
| -rw-r--r-- | src/corelib/global/qlogging.cpp | 29 |
1 files changed, 28 insertions, 1 deletions
diff --git a/src/corelib/global/qlogging.cpp b/src/corelib/global/qlogging.cpp index 7444145e82..583364a146 100644 --- a/src/corelib/global/qlogging.cpp +++ b/src/corelib/global/qlogging.cpp @@ -2,7 +2,7 @@ ** ** Copyright (C) 2016 The Qt Company Ltd. ** Copyright (C) 2016 Olivier Goffart <ogoffart@woboq.com> -** Copyright (C) 2016 Intel Corporation. +** Copyright (C) 2018 Intel Corporation. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the QtCore module of the Qt Toolkit. @@ -61,6 +61,9 @@ #ifdef Q_OS_WIN #include <qt_windows.h> #endif +#ifdef Q_CC_MSVC +#include <intrin.h> +#endif #if QT_CONFIG(slog2) #include <sys/slog2.h> #endif @@ -1839,7 +1842,31 @@ static void qt_message_fatal(QtMsgType, const QMessageLogContext &context, const Q_UNUSED(message); #endif +#ifdef Q_OS_WIN + // std::abort() in the MSVC runtime will call _exit(3) if the abort + // behavior is _WRITE_ABORT_MSG - see also _set_abort_behavior(). This is + // the default for a debug-mode build of the runtime. Worse, MinGW's + // std::abort() implementation (in msvcrt.dll) is basically a call to + // _exit(3) too. Unfortunately, _exit() and _Exit() *do* run the static + // destructors of objects in DLLs, a violation of the C++ standard (see + // [support.start.term]). So we bypass std::abort() and directly + // terminate the application. + +# ifdef Q_CC_MSVC + if (IsProcessorFeaturePresent(PF_FASTFAIL_AVAILABLE)) + __fastfail(FAST_FAIL_FATAL_APP_EXIT); +# else + RaiseFailFastException(nullptr, nullptr, 0); +# endif + + // Fallback + TerminateProcess(GetCurrentProcess(), STATUS_FATAL_APP_EXIT); + + // Tell the compiler the application has stopped. + Q_UNREACHABLE_IMPL(); +#else // !Q_OS_WIN std::abort(); +#endif } |