Bug 297234

Application: kwin (4.8.1 (4.8.1))
KDE Platform Version: 4.8.1 (4.8.1)
Qt Version: 4.8.0
Operating System: Linux 3.2.0-20-generic x86_64
Distribution: Ubuntu precise (development branch)

-- Information about the crash:
- What I was doing when the application crashed:
It seems do be triggered by switching windows trough alt+tab although not exactly at that time...?

-- Backtrace:
Application: KWin (kwin), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f3adddba780 (LWP 19347))]

Thread 2 (Thread 0x7f3ac1a4f700 (LWP 19602)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007f3ada0a7212 in ?? () from /usr/lib/x86_64-linux-gnu/libQtScript.so.4
#2  0x00007f3ada0a7249 in ?? () from /usr/lib/x86_64-linux-gnu/libQtScript.so.4
#3  0x00007f3ad1f3ee9a in start_thread (arg=0x7f3ac1a4f700) at pthread_create.c:308
#4  0x00007f3add5ef4bd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#5  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f3adddba780 (LWP 19347)):
[KCrash Handler]
#6  0x00007f3ac256d6df in testAttribute (attribute=Qt::WA_WState_Visible, this=0x0) at /usr/include/qt4/QtGui/qwidget.h:1041
#7  testAttribute (attribute=Qt::WA_WState_Visible, this=0x0) at ../../../kwin/effects/presentwindows/presentwindows.cpp:1834
#8  isVisible (this=0x0) at /usr/include/qt4/QtGui/qwidget.h:1003
#9  KWin::PresentWindowsEffect::updateCloseWindow (this=0xa65a60) at ../../../kwin/effects/presentwindows/presentwindows.cpp:1842
#10 0x00007f3ac2579500 in KWin::PresentWindowsEffect::slotWindowClosed (this=0xa65a60, w=0xa839c0) at ../../../kwin/effects/presentwindows/presentwindows.cpp:475
#11 0x00007f3ad8e278f1 in QMetaObject::activate (sender=0x9e24b0, m=<optimized out>, local_signal_index=<optimized out>, argv=0x7fff4b225ca0) at kernel/qobject.cpp:3547
#12 0x00007f3adb757af2 in KWin::EffectsHandler::windowClosed (this=<optimized out>, _t1=0xa839c0) at ./kwineffects.moc:257
#13 0x00007f3ad8e278f1 in QMetaObject::activate (sender=0xa2a910, m=<optimized out>, local_signal_index=<optimized out>, argv=0x7fff4b225df0) at kernel/qobject.cpp:3547
#14 0x00007f3add967aaf in KWin::Toplevel::windowClosed (this=<optimized out>, _t1=0xa2a910, _t2=0xb5c2b0) at ./toplevel.moc:151
#15 0x00007f3add90c6cd in KWin::Client::releaseWindow (this=0xa2a910, on_shutdown=false) at ../../kwin/client.cpp:257
#16 0x00007f3add925779 in KWin::Client::windowEvent (this=0xa2a910, e=0x7fff4b2265f0) at ../../kwin/events.cpp:582
#17 0x00007f3add925d8d in KWin::Workspace::workspaceEvent (this=0x9b4ba0, e=0x7fff4b2265f0) at ../../kwin/events.cpp:293
#18 0x00007f3add917fa8 in KWin::Application::x11EventFilter (this=0x7fff4b226900, e=0x7fff4b2265f0) at ../../kwin/main.cpp:359
#19 0x00007f3ad82059a5 in qt_x11EventFilter (ev=0x7fff4b2265f0) at kernel/qapplication_x11.cpp:441
#20 qt_x11EventFilter (ev=0x7fff4b2265f0) at kernel/qapplication_x11.cpp:429
#21 0x00007f3ad8214db8 in QApplication::x11ProcessEvent (this=0x7fff4b226900, event=0x7fff4b2265f0) at kernel/qapplication_x11.cpp:3444
#22 0x00007f3ad823f8fa in QEventDispatcherX11::processEvents (this=0x7b8ad0, flags=...) at kernel/qeventdispatcher_x11.cpp:132
#23 0x00007f3ad8e122f2 in QEventLoop::processEvents (this=<optimized out>, flags=...) at kernel/qeventloop.cpp:149
#24 0x00007f3ad8e12547 in QEventLoop::exec (this=0x7fff4b226840, flags=...) at kernel/qeventloop.cpp:204
#25 0x00007f3ad8e175d7 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1148
#26 0x00007f3add91a726 in kdemain (argc=<optimized out>, argv=<optimized out>) at ../../kwin/main.cpp:541
#27 0x00007f3add51e76d in __libc_start_main (main=0x400630 <main(int, char**)>, argc=3, ubp_av=0x7fff4b227028, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fff4b227018) at libc-start.c:226
#28 0x0000000000400661 in _start ()

Reported using DrKonqi