D18245: [DrKonqi] Create QApplication in a scope to fix possible deadlock

[Christoph Roick]

croick added a comment.


  A backtrace where it gets stuck in the destructor of QApplication.
  
    (gdb) info thread
      Id   Target Id                                          Frame 
    * 1    Thread 0x7ffff36a2f80 (LWP 6015) "testqt"          0x00007ffff6906f6d in __pthread_timedjoin_ex () from /usr/lib/libpthread.so.0
      3    Thread 0x7fffe9642700 (LWP 6026) "testqt:disk$0"   0x00007ffff690bafc in pthread_cond_wait@@GLIBC_2.3.2 ()
       from /usr/lib/libpthread.so.0
      4    Thread 0x7fffe8e41700 (LWP 6027) "QDBusConnection" 0x00007ffff6a0fc21 in poll () from /usr/lib/libc.so.6
    (gdb) thread apply all bt
    
    Thread 4 (Thread 0x7fffe8e41700 (LWP 6027)):
    #0  0x00007ffff6a0fc21 in poll () from /usr/lib/libc.so.6
    #1  0x00007ffff5e81540 in ?? () from /usr/lib/libglib-2.0.so.0
    #2  0x00007ffff5e8162e in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
    #3  0x00007ffff70e3ce9 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
    #4  0x00007ffff708cb2c in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
    #5  0x00007ffff6ed0569 in QThread::exec() () from /usr/lib/libQt5Core.so.5
    #6  0x00007ffff3108ba6 in ?? () from /usr/lib/libQt5DBus.so.5
    #7  0x00007ffff6ed196c in ?? () from /usr/lib/libQt5Core.so.5
    #8  0x00007ffff6905a9d in start_thread () from /usr/lib/libpthread.so.0
    #9  0x00007ffff6a1ab23 in clone () from /usr/lib/libc.so.6
    
    Thread 3 (Thread 0x7fffe9642700 (LWP 6026)):
    #0  0x00007ffff690bafc in pthread_cond_wait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
    #1  0x00007fffe9c5ec94 in ?? () from /usr/lib/dri/i965_dri.so
    #2  0x00007fffe9c5e9b8 in ?? () from /usr/lib/dri/i965_dri.so
    #3  0x00007ffff6905a9d in start_thread () from /usr/lib/libpthread.so.0
    #4  0x00007ffff6a1ab23 in clone () from /usr/lib/libc.so.6
    
    Thread 1 (Thread 0x7ffff36a2f80 (LWP 6015)):
    #0  0x00007ffff6906f6d in __pthread_timedjoin_ex () from /usr/lib/libpthread.so.0
    #1  0x00007fffe9c5ea71 in ?? () from /usr/lib/dri/i965_dri.so
    #2  0x00007fffe9c5f309 in ?? () from /usr/lib/dri/i965_dri.so
    #3  0x00007fffe9c5a73a in ?? () from /usr/lib/dri/i965_dri.so
    #4  0x00007fffe9be4344 in ?? () from /usr/lib/dri/i965_dri.so
    #5  0x00007fffe9c563cf in ?? () from /usr/lib/dri/i965_dri.so
    #6  0x00007fffeaafb07c in ?? () from /usr/lib/libGLX_mesa.so.0
    #7  0x00007fffeaae7822 in ?? () from /usr/lib/libGLX_mesa.so.0
    #8  0x00007fffeaae78a9 in ?? () from /usr/lib/libGLX_mesa.so.0
    #9  0x00007fffeaae79fe in ?? () from /usr/lib/libGLX_mesa.so.0
    #10 0x00007ffff5cc03e2 in XCloseDisplay () from /usr/lib/libX11.so.6
    #11 0x00007ffff31f1f52 in ?? () from /usr/lib/libQt5XcbQpa.so.5
    #12 0x00007ffff31c711a in QXcbConnection::~QXcbConnection() () from /usr/lib/libQt5XcbQpa.so.5
    #13 0x00007ffff31c83d7 in QXcbIntegration::~QXcbIntegration() () from /usr/lib/libQt5XcbQpa.so.5
    #14 0x00007ffff31c84da in QXcbIntegration::~QXcbIntegration() () from /usr/lib/libQt5XcbQpa.so.5
    #15 0x00007ffff7455ed9 in QGuiApplicationPrivate::~QGuiApplicationPrivate() () from /usr/lib/libQt5Gui.so.5
    #16 0x00007ffff7a546fa in QApplicationPrivate::~QApplicationPrivate() () from /usr/lib/libQt5Widgets.so.5
    #17 0x00007ffff70bf86f in QObject::~QObject() () from /usr/lib/libQt5Core.so.5
    #18 0x00007ffff70902b0 in QCoreApplication::~QCoreApplication() () from /usr/lib/libQt5Core.so.5
    #19 0x00007ffff7a56842 in QApplication::~QApplication() () from /usr/lib/libQt5Widgets.so.5
    #20 0x0000555555555221 in main (argc=1, argv=0x7fffffffe578) at testqt.cpp:6

REPOSITORY
  R871 DrKonqi

REVISION DETAIL
  https://phabricator.kde.org/D18245

To: croick, sitter, #kdevelop
Cc: dfaure, thiago, ossi, plasma-devel, jraleigh, GB_2, ragreen, Pitel, ZrenBot, lesliezhai, ali-mohamed, jensreuterberg, abetts, sebas, apol, mart
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.kde.org/pipermail/plasma-devel/attachments/20190224/2e89e646/attachment.html>