Application: plasma-desktop (0.4)
KDE Platform Version: 4.7.3 (4.7.3)
Qt Version: 4.7.4
Operating System: Linux 3.0.0-14-generic i686
Distribution: Ubuntu 11.10

-- Information about the crash:
I was just switching between applications with 'ALT-TAB'
Also I was listening to music with the VLC Media Player, and I was browsing the web with Firefox

The crash can be reproduced some of the time.

-- Backtrace:
Application: Plasma Desktop Shell (plasma-desktop), signal: Segmentation fault
[Current thread is 1 (Thread 0xb7755b20 (LWP 1835))]

Thread 4 (Thread 0xb165eb70 (LWP 1882)):
#0  0x07412d10 in clock_gettime () from /lib/i386-linux-gnu/librt.so.1
#1  0x02a8d7d5 in do_gettime (frac=0xb165e010, sec=0xb165e008) at tools/qelapsedtimer_unix.cpp:123
#2  qt_gettime () at tools/qelapsedtimer_unix.cpp:140
#3  0x02b604b6 in QTimerInfoList::updateCurrentTime (this=0xb0d01a7c) at kernel/qeventdispatcher_unix.cpp:339
#4  0x02b6080a in QTimerInfoList::timerWait (this=0xb0d01a7c, tm=...) at kernel/qeventdispatcher_unix.cpp:442
#5  0x02b5f053 in timerSourcePrepareHelper (src=<optimized out>, timeout=0xb165e11c) at kernel/qeventdispatcher_glib.cpp:136
#6  0x02b5f0ed in timerSourcePrepare (source=0xb0d01a48, timeout=<optimized out>) at kernel/qeventdispatcher_glib.cpp:169
#7  0x059c388c in g_main_context_prepare () from /lib/i386-linux-gnu/libglib-2.0.so.0
#8  0x059c4637 in ?? () from /lib/i386-linux-gnu/libglib-2.0.so.0
#9  0x059c4c2a in g_main_context_iteration () from /lib/i386-linux-gnu/libglib-2.0.so.0
#10 0x02b5fb37 in QEventDispatcherGlib::processEvents (this=0x91b1450, flags=...) at kernel/qeventdispatcher_glib.cpp:424
#11 0x02b301dd in QEventLoop::processEvents (this=0xb165e2a0, flags=...) at kernel/qeventloop.cpp:149
#12 0x02b30421 in QEventLoop::exec (this=0xb165e2a0, flags=...) at kernel/qeventloop.cpp:201
#13 0x02a3390b in QThread::exec (this=0x91afd10) at thread/qthread.cpp:498
#14 0x02b10e2d in QInotifyFileSystemWatcherEngine::run (this=0x91afd10) at io/qfilesystemwatcher_inotify.cpp:248
#15 0x02a367b3 in QThreadPrivate::start (arg=0x91afd10) at thread/qthread_unix.cpp:331
#16 0x04ee7d31 in start_thread () from /lib/i386-linux-gnu/libpthread.so.0
#17 0x002f20ce in clone () from /lib/i386-linux-gnu/libc.so.6
Backtrace stopped: Not enough registers or memory available to unwind further

Thread 3 (Thread 0xafd77b70 (LWP 1883)):
#0  0x005e7416 in __kernel_vsyscall ()
#1  0x002e340e in poll () from /lib/i386-linux-gnu/libc.so.6
#2  0x059d334b in g_poll () from /lib/i386-linux-gnu/libglib-2.0.so.0
#3  0x059c4896 in ?? () from /lib/i386-linux-gnu/libglib-2.0.so.0
#4  0x059c4c2a in g_main_context_iteration () from /lib/i386-linux-gnu/libglib-2.0.so.0
#5  0x02b5fb37 in QEventDispatcherGlib::processEvents (this=0xb0d01ba8, flags=...) at kernel/qeventdispatcher_glib.cpp:424
#6  0x02b301dd in QEventLoop::processEvents (this=0xafd772a0, flags=...) at kernel/qeventloop.cpp:149
#7  0x02b30421 in QEventLoop::exec (this=0xafd772a0, flags=...) at kernel/qeventloop.cpp:201
#8  0x02a3390b in QThread::exec (this=0x8de1540) at thread/qthread.cpp:498
#9  0x02b10e2d in QInotifyFileSystemWatcherEngine::run (this=0x8de1540) at io/qfilesystemwatcher_inotify.cpp:248
#10 0x02a367b3 in QThreadPrivate::start (arg=0x8de1540) at thread/qthread_unix.cpp:331
#11 0x04ee7d31 in start_thread () from /lib/i386-linux-gnu/libpthread.so.0
#12 0x002f20ce in clone () from /lib/i386-linux-gnu/libc.so.6
Backtrace stopped: Not enough registers or memory available to unwind further

Thread 2 (Thread 0xadaf5b70 (LWP 1891)):
#0  0x04eead44 in __pthread_mutex_unlock_usercnt () from /lib/i386-linux-gnu/libpthread.so.0
#1  0x002fff54 in pthread_mutex_unlock () from /lib/i386-linux-gnu/libc.so.6
#2  0x059c4785 in ?? () from /lib/i386-linux-gnu/libglib-2.0.so.0
#3  0x059c4f9b in g_main_loop_run () from /lib/i386-linux-gnu/libglib-2.0.so.0
#4  0x067dfcea in ?? () from /usr/lib/i386-linux-gnu/libgio-2.0.so.0
#5  0x059eb5f4 in ?? () from /lib/i386-linux-gnu/libglib-2.0.so.0
#6  0x04ee7d31 in start_thread () from /lib/i386-linux-gnu/libpthread.so.0
#7  0x002f20ce in clone () from /lib/i386-linux-gnu/libc.so.6
Backtrace stopped: Not enough registers or memory available to unwind further

Thread 1 (Thread 0xb7755b20 (LWP 1835)):
[KCrash Handler]
#7  isNull (this=0x1) at /usr/include/qt4/QtCore/qsharedpointer_impl.h:568
#8  operator! (this=0x1) at /usr/include/qt4/QtCore/qsharedpointer_impl.h:574
#9  TaskManager::TaskItem::task (this=0x91c68f0) at ../../../libs/taskmanager/taskitem.cpp:113
#10 0x0520b590 in WindowTaskItem::publishIconGeometry (this=0xa0d42f0, rect=...) at ../../../../../plasma/desktop/applets/tasks/windowtaskitem.cpp:130
#11 0x0521db24 in TaskGroupItem::publishIconGeometry (this=0x9406ab8, rect=...) at ../../../../../plasma/desktop/applets/tasks/taskgroupitem.cpp:1438
#12 0x0521d801 in publishIconGeometry (this=0x9406ab8) at ../../../../../plasma/desktop/applets/tasks/taskgroupitem.cpp:1424
#13 TaskGroupItem::publishIconGeometry (this=0x9406ab8) at ../../../../../plasma/desktop/applets/tasks/taskgroupitem.cpp:1416
#14 0x0521c688 in AbstractTaskItem::timerEvent (this=0x9406ab8, event=0xbf97e17c) at ../../../../../plasma/desktop/applets/tasks/abstracttaskitem.cpp:439
#15 0x02b49994 in QObject::event (this=0x9406ab8, e=0xbf97e17c) at kernel/qobject.cpp:1181
#16 0x01c16bd4 in QGraphicsWidget::event (this=0x9406ab8, event=0xbf97e17c) at graphicsview/qgraphicswidget.cpp:1455
#17 0x01557d54 in notify_helper (e=0xbf97e17c, receiver=0x9406ab8, this=0x89ca1e8) at kernel/qapplication.cpp:4486
#18 QApplicationPrivate::notify_helper (this=0x89ca1e8, receiver=0x9406ab8, e=0xbf97e17c) at kernel/qapplication.cpp:4458
#19 0x0155d103 in QApplication::notify (this=0xbf97e17c, receiver=0x9406ab8, e=0xbf97e17c) at kernel/qapplication.cpp:3886
#20 0x011ae681 in KApplication::notify (this=0x89bfb28, receiver=0x9406ab8, event=0xbf97e17c) at ../../kdeui/kernel/kapplication.cpp:311
#21 0x02b3119e in QCoreApplication::notifyInternal (this=0x89bfb28, receiver=0x9406ab8, event=0xbf97e17c) at kernel/qcoreapplication.cpp:787
#22 0x02b61c10 in sendEvent (event=0xbf97e17c, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#23 QTimerInfoList::activateTimers (this=0x89cdebc) at kernel/qeventdispatcher_unix.cpp:603
#24 0x02b5f155 in timerSourceDispatch (source=<optimized out>) at kernel/qeventdispatcher_glib.cpp:184
#25 idleTimerSourceDispatch (source=0x89cdef0) at kernel/qeventdispatcher_glib.cpp:231
#26 0x059c425f in g_main_context_dispatch () from /lib/i386-linux-gnu/libglib-2.0.so.0
#27 0x059c4990 in ?? () from /lib/i386-linux-gnu/libglib-2.0.so.0
#28 0x059c4c2a in g_main_context_iteration () from /lib/i386-linux-gnu/libglib-2.0.so.0
#29 0x02b5fada in QEventDispatcherGlib::processEvents (this=0x8981218, flags=...) at kernel/qeventdispatcher_glib.cpp:422
#30 0x0160fe3a in QGuiEventDispatcherGlib::processEvents (this=0x8981218, flags=...) at kernel/qguieventdispatcher_glib.cpp:204
#31 0x02b301dd in QEventLoop::processEvents (this=0xbf97e3f4, flags=...) at kernel/qeventloop.cpp:149
#32 0x02b30421 in QEventLoop::exec (this=0xbf97e3f4, flags=...) at kernel/qeventloop.cpp:201
#33 0x02b3519d in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1064
#34 0x015558f4 in QApplication::exec () at kernel/qapplication.cpp:3760
#35 0x0014518b in kdemain (argc=1, argv=0xbf97e5f4) at ../../../../plasma/desktop/shell/main.cpp:120
#36 0x0804850b in main (argc=1, argv=0xbf97e5f4) at plasma-desktop_dummy.cpp:3

Possible duplicates by query: bug 290926, bug 290881, bug 290870, bug 290859, bug 290813.

Reported using DrKonqi