Bug 356144

Application: kwin_x11 (5.4.2)

Qt Version: 5.4.2
Operating System: Linux 4.2.0-18-generic i686
Distribution: Ubuntu 15.10

-- Information about the crash:
- What I was doing when the application crashed:
I was using Konsole and wanted to switch to different program with the <Alt>+<Tab> and KWin crashed. 

This could be a duplicate of Bug 349174.

The crash can be reproduced sometimes.

-- Backtrace:
Application: KWin (kwin_x11), signal: Segmentation fault
Using host libthread_db library "/lib/i386-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0xb16757c0 (LWP 8635))]

Thread 4 (Thread 0xaefafb40 (LWP 8653)):
#0  0xb776e946 in __vdso_clock_gettime ()
#1  0xb7675740 in __GI___clock_gettime (clock_id=1, tp=0xaefaf064) at ../sysdeps/unix/clock_gettime.c:115
#2  0xb61cb378 in qt_clock_gettime (ts=0xaefaf064, clock=<optimized out>) at tools/qelapsedtimer_unix.cpp:105
#3  do_gettime (frac=<synthetic pointer>, sec=<synthetic pointer>) at tools/qelapsedtimer_unix.cpp:161
#4  qt_gettime () at tools/qelapsedtimer_unix.cpp:170
#5  0xb635b0a2 in QTimerInfoList::updateCurrentTime (this=0xae600af0) at kernel/qtimerinfo_unix.cpp:84
#6  0xb635b5b4 in QTimerInfoList::timerWait (this=0xae600af0, tm=...) at kernel/qtimerinfo_unix.cpp:379
#7  0xb635aba4 in QEventDispatcherUNIX::processEvents (this=0xae600468, flags=...) at kernel/qeventdispatcher_unix.cpp:594
#8  0xb63002b3 in QEventLoop::processEvents (this=0xaefaf214, flags=...) at kernel/qeventloop.cpp:128
#9  0xb6300702 in QEventLoop::exec (this=0xaefaf214, flags=...) at kernel/qeventloop.cpp:204
#10 0xb612923d in QThread::exec (this=0x9bfa620) at thread/qthread.cpp:503
#11 0xb4f443bf in ?? () from /usr/lib/i386-linux-gnu/libQt5Qml.so.5
#12 0xb612e65b in QThreadPrivate::start (arg=0x9bfa620) at thread/qthread_unix.cpp:337
#13 0xb725d1aa in start_thread (arg=0xaefafb40) at pthread_create.c:333
#14 0xb7667fde in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:122

Thread 3 (Thread 0xaddffb40 (LWP 8656)):
#0  0xb776ebe8 in __kernel_vsyscall ()
#1  0xb726225c in pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/i386/i686/../i486/pthread_cond_wait.S:187
#2  0xb7674cf6 in __pthread_cond_wait (cond=0xb5dba8d0, mutex=0xb5dba8b8) at forward.c:149
#3  0xb5c822fc in ?? () from /usr/lib/i386-linux-gnu/libQt5Script.so.5
#4  0xb5c8233c in ?? () from /usr/lib/i386-linux-gnu/libQt5Script.so.5
#5  0xb725d1aa in start_thread (arg=0xaddffb40) at pthread_create.c:333
#6  0xb7667fde in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:122

Thread 2 (Thread 0xafa3bb40 (LWP 8918)):
#0  0xb776e946 in __vdso_clock_gettime ()
#1  0xb7675740 in __GI___clock_gettime (clock_id=1, tp=0xafa3afb4) at ../sysdeps/unix/clock_gettime.c:115
#2  0xb61cb378 in qt_clock_gettime (ts=0xafa3afb4, clock=<optimized out>) at tools/qelapsedtimer_unix.cpp:105
#3  do_gettime (frac=<synthetic pointer>, sec=<synthetic pointer>) at tools/qelapsedtimer_unix.cpp:161
#4  qt_gettime () at tools/qelapsedtimer_unix.cpp:170
#5  0xb635b0a2 in QTimerInfoList::updateCurrentTime (this=0xaf100af0) at kernel/qtimerinfo_unix.cpp:84
#6  0xb635a656 in QEventDispatcherUNIXPrivate::doSelect (this=0xaf100478, flags=..., timeout=0x0) at kernel/qeventdispatcher_unix.cpp:171
#7  0xb635abd6 in QEventDispatcherUNIX::processEvents (this=0xaf100468, flags=...) at kernel/qeventdispatcher_unix.cpp:607
#8  0xb63002b3 in QEventLoop::processEvents (this=0xafa3b214, flags=...) at kernel/qeventloop.cpp:128
#9  0xb6300702 in QEventLoop::exec (this=0xafa3b214, flags=...) at kernel/qeventloop.cpp:204
#10 0xb612923d in QThread::exec (this=0x9be4f18) at thread/qthread.cpp:503
#11 0xb4f443bf in ?? () from /usr/lib/i386-linux-gnu/libQt5Qml.so.5
#12 0xb612e65b in QThreadPrivate::start (arg=0x9be4f18) at thread/qthread_unix.cpp:337
#13 0xb725d1aa in start_thread (arg=0xafa3bb40) at pthread_create.c:333
#14 0xb7667fde in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:122

Thread 1 (Thread 0xb16757c0 (LWP 8635)):
[KCrash Handler]
#7  0xb6641de4 in QScreen::handle (this=0x0) at kernel/qscreen.cpp:85
#8  0xb12ad681 in QXcbWindow::QXcbWindow (this=0xd3e7cd8, window=0xb5584a8) at qxcbwindow.cpp:260
#9  0xb1298c65 in QXcbIntegration::createPlatformWindow (this=0x9a78ce8, window=0xb5584a8) at qxcbintegration.cpp:194
#10 0xb661c885 in QWindowPrivate::create (this=0xb186ff0, recursive=false) at kernel/qwindow.cpp:395
#11 0xb661caad in QWindow::create (this=0xb5584a8) at kernel/qwindow.cpp:546
#12 0xb661ccd9 in QWindow::winId (this=0xb5584a8) at kernel/qwindow.cpp:565
#13 0xa83e5723 in PlasmaQuick::DialogPrivate::updateInputShape (this=0xb39e118) at ../../../src/plasmaquick/dialog.cpp:544
#14 0xa83e8143 in PlasmaQuick::Dialog::qt_static_metacall (_o=0xb5584a8, _c=QMetaObject::InvokeMetaMethod, _id=10, _a=0xbfcf0ab4) at ./moc_dialog.cpp:221
#15 0xb63360e1 in QMetaObject::activate (sender=0xb5584a8, signalOffset=3, local_signal_index=12, argv=0xbfcf0ab4) at kernel/qobject.cpp:3717
#16 0xb63365dd in QMetaObject::activate (sender=0xb5584a8, m=0xb6ac9430 <QWindow::staticMetaObject>, local_signal_index=12, argv=0xbfcf0ab4) at kernel/qobject.cpp:3582
#17 0xb661bc29 in QWindow::visibleChanged (this=0xb5584a8, _t1=true) at .moc/moc_qwindow.cpp:710
#18 0xb661f617 in QWindow::setVisible (this=0xb5584a8, visible=true) at kernel/qwindow.cpp:471
#19 0xa83e559a in PlasmaQuick::Dialog::setVisible (this=0xb5584a8, visible=true) at ../../../src/plasmaquick/dialog.cpp:1235
#20 0xa83ea617 in PlasmaQuick::Dialog::qt_metacall (this=0xb5584a8, _c=QMetaObject::WriteProperty, _id=9, _a=0xbfcf0c8c) at ./moc_dialog.cpp:376
#21 0xb630ac02 in QMetaObject::metacall (object=0xb5584a8, cl=QMetaObject::WriteProperty, idx=30, argv=0xbfcf0c8c) at kernel/qmetaobject.cpp:295
#22 0xb4ebd1a6 in QQmlPropertyPrivate::write(QObject*, QQmlPropertyData const&, QVariant const&, QQmlContextData*, QFlags<QQmlPropertyPrivate::WriteFlag>) () from /usr/lib/i386-linux-gnu/libQt5Qml.so.5
#23 0xb4ebe5c5 in QQmlPropertyPrivate::writeValueProperty(QObject*, QQmlPropertyData const&, QVariant const&, QQmlContextData*, QFlags<QQmlPropertyPrivate::WriteFlag>) () from /usr/lib/i386-linux-gnu/libQt5Qml.so.5
#24 0xb4ebf0c5 in QQmlPropertyPrivate::writeBinding(QObject*, QQmlPropertyData const&, QQmlContextData*, QQmlJavaScriptExpression*, QV4::ValueRef, bool, QFlags<QQmlPropertyPrivate::WriteFlag>) () from /usr/lib/i386-linux-gnu/libQt5Qml.so.5
#25 0xb4f338f0 in QQmlBinding::update(QFlags<QQmlPropertyPrivate::WriteFlag>) () from /usr/lib/i386-linux-gnu/libQt5Qml.so.5
#26 0xb4f33fd8 in QQmlBinding::expressionChanged(QQmlJavaScriptExpression*) () from /usr/lib/i386-linux-gnu/libQt5Qml.so.5
#27 0xb4f2b33a in ?? () from /usr/lib/i386-linux-gnu/libQt5Qml.so.5
#28 0xb4f0c7a3 in QQmlNotifier::emitNotify(QQmlNotifierEndpoint*, void**) () from /usr/lib/i386-linux-gnu/libQt5Qml.so.5
#29 0xb4ea9ee1 in QQmlData::signalEmitted(QAbstractDeclarativeData*, QObject*, int, void**) () from /usr/lib/i386-linux-gnu/libQt5Qml.so.5
#30 0xb6335885 in QMetaObject::activate (sender=0xb181480, signalOffset=3, local_signal_index=0, argv=0x0) at kernel/qobject.cpp:3603
#31 0xb63365dd in QMetaObject::activate (sender=0xb181480, m=0xb75790f8 <KWin::TabBox::SwitcherItem::staticMetaObject>, local_signal_index=0, argv=0x0) at kernel/qobject.cpp:3582
#32 0xb7477613 in KWin::TabBox::SwitcherItem::visibleChanged (this=0xb181480) at moc_switcheritem.cpp:244
#33 0xb745191d in KWin::TabBox::SwitcherItem::setVisible (this=0xb181480, visible=true) at ../tabbox/switcheritem.cpp:76
#34 0xb7455b43 in KWin::TabBox::TabBoxHandlerPrivate::show (this=0x9b35c80) at ../tabbox/tabboxhandler.cpp:347
#35 0xb7455dcb in KWin::TabBox::TabBoxHandler::show (this=0x9b35ae0) at ../tabbox/tabboxhandler.cpp:385
#36 0xb744613b in KWin::TabBox::TabBox::show (this=0x9b35a38) at ../tabbox/tabbox.cpp:742
#37 0xb7479431 in KWin::TabBox::TabBox::qt_static_metacall (_o=0x9b35a38, _c=QMetaObject::InvokeMetaMethod, _id=4, _a=0xbfcf1288) at moc_tabbox.cpp:174
#38 0xb63360e1 in QMetaObject::activate (sender=0x9b35a50, signalOffset=3, local_signal_index=0, argv=0x0) at kernel/qobject.cpp:3717
#39 0xb63365dd in QMetaObject::activate (sender=0x9b35a50, m=0xb655b444 <QTimer::staticMetaObject>, local_signal_index=0, argv=0x0) at kernel/qobject.cpp:3582
#40 0xb63b2a72 in QTimer::timeout (this=0x9b35a50) at .moc/moc_qtimer.cpp:192
#41 0xb6342e11 in QTimer::timerEvent (this=0x9b35a50, e=0xbfcf15dc) at kernel/qtimer.cpp:247
#42 0xb6336cce in QObject::event (this=0x9b35a50, e=0xbfcf15dc) at kernel/qobject.cpp:1267
#43 0xb6bbddaa in QApplicationPrivate::notify_helper (this=0x9a76e98, receiver=0x9b35a50, e=0xbfcf15dc) at kernel/qapplication.cpp:3720
#44 0xb6bc367f in QApplication::notify (this=0xbfcf1820, receiver=0x9b35a50, e=0xbfcf15dc) at kernel/qapplication.cpp:3503
#45 0xb734045a in KWin::Application::notify (this=0xbfcf1820, o=0x9b35a50, e=0xbfcf15dc) at ../main.cpp:246
#46 0xb63030ff in QCoreApplication::notifyInternal (this=0xbfcf1820, receiver=0x9b35a50, event=0xbfcf15dc) at kernel/qcoreapplication.cpp:935
#47 0xb635c4eb in QCoreApplication::sendEvent (event=0xbfcf15dc, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:228
#48 QTimerInfoList::activateTimers (this=0x9a9eb78) at kernel/qtimerinfo_unix.cpp:635
#49 0xb635a321 in QEventDispatcherUNIX::activateTimers (this=0x9aa0ed8) at kernel/qeventdispatcher_unix.cpp:549
#50 0xb635abe4 in QEventDispatcherUNIX::processEvents (this=0x9aa0ed8, flags=...) at kernel/qeventdispatcher_unix.cpp:611
#51 0xb12effef in QUnixEventDispatcherQPA::processEvents (this=0x9aa0ed8, flags=...) at eventdispatchers/qunixeventdispatcher.cpp:62
#52 0xb63002b3 in QEventLoop::processEvents (this=0xbfcf1758, flags=...) at kernel/qeventloop.cpp:128
#53 0xb6300702 in QEventLoop::exec (this=0xbfcf1758, flags=...) at kernel/qeventloop.cpp:204
#54 0xb63087e5 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1188
#55 0xb660ecf1 in QGuiApplication::exec () at kernel/qguiapplication.cpp:1510
#56 0xb6bb9cb4 in QApplication::exec () at kernel/qapplication.cpp:2956
#57 0xb773d60b in kdemain (argc=1, argv=0xbfcf1934) at ../main_x11.cpp:303
#58 0x08048607 in main (argc=1, argv=0xbfcf1934) at kwin_x11_dummy.cpp:3

Possible duplicates by query: bug 355118, bug 354387, bug 353122, bug 352712, bug 350800.

Reported using DrKonqi