Application: kwin (4.6.2 (4.6.2))
KDE Platform Version: 4.6.2 (4.6.2) (Compiled from sources)
Qt Version: 4.7.2
Operating System: Linux 2.6.38-8-generic x86_64
Distribution: Ubuntu 11.04

-- Information about the crash:
Kwin closed when I was trying to close a pogram and I pressed alt+tab and it crashed.- What I was doing when the application crashed:

-- Backtrace:
Application: KWin (kwin), signal: Segmentation fault
[Current thread is 1 (Thread 0x7ff1d5ca17a0 (LWP 1497))]

Thread 3 (Thread 0x7ff1bba14700 (LWP 1504)):
#0  0x00007ff1d54e7143 in select () at ../sysdeps/unix/syscall-template.S:82
#1  0x00007ff1d193d32c in qt_safe_select (nfds=16, fdread=0x2673c30, fdwrite=0x2673ec8, fdexcept=0x2674160, orig_timeout=<value optimized out>) at kernel/qcore_unix.cpp:82
#2  0x00007ff1d19423d0 in QEventDispatcherUNIXPrivate::doSelect (this=0x2673a70, flags=..., timeout=0x0) at kernel/qeventdispatcher_unix.cpp:219
#3  0x00007ff1d194304a in QEventDispatcherUNIX::processEvents (this=0x26d73b0, flags=...) at kernel/qeventdispatcher_unix.cpp:919
#4  0x00007ff1d1914882 in QEventLoop::processEvents (this=<value optimized out>, flags=...) at kernel/qeventloop.cpp:149
#5  0x00007ff1d1914abc in QEventLoop::exec (this=0x7ff1bba13db0, flags=...) at kernel/qeventloop.cpp:201
#6  0x00007ff1d182b924 in QThread::exec (this=<value optimized out>) at thread/qthread.cpp:492
#7  0x00007ff1d18f6c2f in QInotifyFileSystemWatcherEngine::run (this=0x256ea80) at io/qfilesystemwatcher_inotify.cpp:248
#8  0x00007ff1d182e175 in QThreadPrivate::start (arg=0x256ea80) at thread/qthread_unix.cpp:320
#9  0x00007ff1cbf21d8c in start_thread (arg=0x7ff1bba14700) at pthread_create.c:304
#10 0x00007ff1d54ef04d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#11 0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7ff1bb213700 (LWP 1505)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007ff1d434e2a2 in QTWTF::TCMalloc_PageHeap::scavengerThread (this=0x7ff1d4667180) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:2359
#2  0x00007ff1d434e2d9 in QTWTF::TCMalloc_PageHeap::runScavengerThread (context=0x7ff1d4675254) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:1464
#3  0x00007ff1cbf21d8c in start_thread (arg=0x7ff1bb213700) at pthread_create.c:304
#4  0x00007ff1d54ef04d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#5  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7ff1d5ca17a0 (LWP 1497)):
[KCrash Handler]
#6  0x00007ff1d3fb81b8 in ?? () from /usr/lib/libkephal.so.4
#7  0x00007ff1d393b084 in KWin::WindowPaintData::WindowPaintData (this=0x7fffb384a4e0, w=0x2348330) at ../../../kwin/lib/kwineffects.cpp:78
#8  0x00007ff1bd49ac4a in KWin::CoverSwitchEffect::paintFrontWindow (this=0x24cba60, frontWindow=0x2348330, width=1920, leftWindows=0, rightWindows=0, reflectedWindow=true) at ../../../kwin/effects/coverswitch/coverswitch.cpp:789
#9  0x00007ff1bd49b2a5 in KWin::CoverSwitchEffect::paintScene (this=0x24cba60, frontWindow=0x2348330, leftWindows=..., rightWindows=..., reflectedWindows=<value optimized out>) at ../../../kwin/effects/coverswitch/coverswitch.cpp:463
#10 0x00007ff1bd49ca0d in KWin::CoverSwitchEffect::paintScreen (this=0x24cba60, mask=<value optimized out>, region=..., data=<value optimized out>) at ../../../kwin/effects/coverswitch/coverswitch.cpp:254
#11 0x00007ff1d5878fa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x23b4330, mask=32, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#12 0x00007ff1d3938a18 in KWin::Effect::paintScreen (this=<value optimized out>, mask=32, region=<value optimized out>, data=...) at ../../../kwin/lib/kwineffects.cpp:227
#13 0x00007ff1d5878fa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x23b4330, mask=32, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#14 0x00007ff1d3938a18 in KWin::Effect::paintScreen (this=<value optimized out>, mask=32, region=<value optimized out>, data=...) at ../../../kwin/lib/kwineffects.cpp:227
#15 0x00007ff1d5878fa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x23b4330, mask=32, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#16 0x00007ff1bd49239b in KWin::ZoomEffect::paintScreen (this=0x24ac370, mask=32, region=..., data=...) at ../../../kwin/effects/zoom/zoom.cpp:341
#17 0x00007ff1d5878fa3 in KWin::EffectsHandlerImpl::paintScreen (this=0x23b4330, mask=32, region=<value optimized out>, data=...) at ../../kwin/effects.cpp:169
#18 0x00007ff1d585d0af in KWin::Scene::paintScreen (this=0x23b0620, mask=0x7fffb384ac1c, region=0x7fffb384ace0) at ../../kwin/scene.cpp:137
#19 0x00007ff1d5870ef3 in KWin::SceneOpenGL::paint (this=0x23b0620, damage=..., toplevels=<value optimized out>) at ../../kwin/scene_opengl.cpp:772
#20 0x00007ff1d5858396 in KWin::Workspace::performCompositing (this=0x23dc890) at ../../kwin/composite.cpp:448
#21 0x00007ff1d19291c9 in QObject::event (this=0x23dc890, e=<value optimized out>) at kernel/qobject.cpp:1190
#22 0x00007ff1d0cd69e4 in QApplicationPrivate::notify_helper (this=0x22a6960, receiver=0x23dc890, e=0x7fffb384b470) at kernel/qapplication.cpp:4462
#23 0x00007ff1d0cdb3aa in QApplication::notify (this=<value optimized out>, receiver=0x23dc890, e=0x7fffb384b470) at kernel/qapplication.cpp:4341
#24 0x00007ff1d4fea866 in KApplication::notify (this=0x7fffb384b870, receiver=0x23dc890, event=0x7fffb384b470) at ../../kdeui/kernel/kapplication.cpp:311
#25 0x00007ff1d191549c in QCoreApplication::notifyInternal (this=0x7fffb384b870, receiver=0x23dc890, event=0x7fffb384b470) at kernel/qcoreapplication.cpp:731
#26 0x00007ff1d1942f12 in sendEvent (this=0x22a7a40) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#27 QTimerInfoList::activateTimers (this=0x22a7a40) at kernel/qeventdispatcher_unix.cpp:604
#28 0x00007ff1d194305b in QEventDispatcherUNIX::processEvents (this=0x224b340, flags=...) at kernel/qeventdispatcher_unix.cpp:923
#29 0x00007ff1d0d7ec0c in QEventDispatcherX11::processEvents (this=0x224b340, flags=...) at kernel/qeventdispatcher_x11.cpp:152
#30 0x00007ff1d1914882 in QEventLoop::processEvents (this=<value optimized out>, flags=...) at kernel/qeventloop.cpp:149
#31 0x00007ff1d1914abc in QEventLoop::exec (this=0x7fffb384b7b0, flags=...) at kernel/qeventloop.cpp:201
#32 0x00007ff1d1918ecb in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1008
#33 0x00007ff1d57f61ec in kdemain (argc=<value optimized out>, argv=0x7fffb384bf08) at ../../kwin/main.cpp:542
#34 0x00007ff1d5427eff in __libc_start_main (main=0x400740 <main(int, char**)>, argc=3, ubp_av=0x7fffb384bf08, init=<value optimized out>, fini=<value optimized out>, rtld_fini=<value optimized out>, stack_end=0x7fffb384bef8) at libc-start.c:226
#35 0x0000000000400669 in _start ()

Possible duplicates by query: bug 267785, bug 265057, bug 264087, bug 255467, bug 242134.

Reported using DrKonqi