Application: kwin (4.6.00 (4.6.0))
KDE Platform Version: 4.6.00 (4.6.0)
Qt Version: 4.7.0
Operating System: Linux 2.6.35-24-generic x86_64
Distribution: Ubuntu 10.10

-- Information about the crash:
- What I was doing when the application crashed:
kwin crashed when I tried to group VirtualBox Manager window with running VM window

-- Backtrace:
Application: KWin (kwin), signal: Segmentation fault
[Current thread is 1 (Thread 0x7fc7a6aab780 (LWP 20445))]

Thread 3 (Thread 0x7fc78c807700 (LWP 20453)):
#0  0x00007fc7a62f92c3 in select () at ../sysdeps/unix/syscall-template.S:82
#1  0x00007fc7a267676e in qt_safe_select (nfds=17, fdread=0x2657900, fdwrite=0x2657b98, fdexcept=0x2657e30, orig_timeout=0x0) at kernel/qcore_unix.cpp:82
#2  0x00007fc7a267bbeb in QEventDispatcherUNIXPrivate::doSelect (this=0x2657740, flags=<value optimized out>, timeout=<value optimized out>) at kernel/qeventdispatcher_unix.cpp:219
#3  0x00007fc7a267c81b in QEventDispatcherUNIX::processEvents (this=0x27a4540, flags=) at kernel/qeventdispatcher_unix.cpp:919
#4  0x00007fc7a264ba02 in QEventLoop::processEvents (this=<value optimized out>, flags=) at kernel/qeventloop.cpp:149
#5  0x00007fc7a264bdec in QEventLoop::exec (this=0x7fc78c806d90, flags=) at kernel/qeventloop.cpp:201
#6  0x00007fc7a25562fd in QThread::exec (this=<value optimized out>) at thread/qthread.cpp:490
#7  0x00007fc7a262b5f8 in QInotifyFileSystemWatcherEngine::run (this=0x265f020) at io/qfilesystemwatcher_inotify.cpp:248
#8  0x00007fc7a255927e in QThreadPrivate::start (arg=0x265f020) at thread/qthread_unix.cpp:266
#9  0x00007fc79cd51971 in start_thread (arg=<value optimized out>) at pthread_create.c:304
#10 0x00007fc7a630092d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#11 0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7fc786eba700 (LWP 20454)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007fc7a511c334 in QTWTF::TCMalloc_PageHeap::scavengerThread (this=0x7fc7a5427160) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:2359
#2  0x00007fc7a511c369 in QTWTF::TCMalloc_PageHeap::runScavengerThread (context=0x7fc7a5435234) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:1464
#3  0x00007fc79cd51971 in start_thread (arg=<value optimized out>) at pthread_create.c:304
#4  0x00007fc7a630092d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#5  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7fc7a6aab780 (LWP 20445)):
[KCrash Handler]
#6  0x000000000301d8a8 in ?? ()
#7  0x00007fc7a578ad58 in Plasma::Corona::popupPosition (this=0x2aceaa0, item=0x2ecc7d0, s=..., alignment=20) at ../../plasma/corona.cpp:858
#8  0x00007fc7a5838ce7 in Plasma::ToolTipManagerPrivate::showToolTip (this=0x24983a0) at ../../plasma/tooltipmanager.cpp:399
#9  0x00007fc7a5838e25 in Plasma::ToolTipManager::qt_metacall (this=0x24a42c0, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7fffb5adf190) at ./tooltipmanager.moc:88
#10 0x00007fc7a2664b27 in QMetaObject::activate (sender=0x27e4930, m=<value optimized out>, local_signal_index=<value optimized out>, argv=0xf7744) at kernel/qobject.cpp:3280
#11 0x00007fc7a265e8f9 in QObject::event (this=0x27e4930, e=0x1) at kernel/qobject.cpp:1183
#12 0x00007fc7a19b3fdc in QApplicationPrivate::notify_helper (this=0x23018f0, receiver=0x27e4930, e=0x7fffb5adf8e0) at kernel/qapplication.cpp:4396
#13 0x00007fc7a19b9aed in QApplication::notify (this=0x7fffb5adfd10, receiver=0x27e4930, e=0x7fffb5adf8e0) at kernel/qapplication.cpp:4277
#14 0x00007fc7a5de5a36 in KApplication::notify (this=0x7fffb5adfd10, receiver=0x27e4930, event=0x7fffb5adf8e0) at ../../kdeui/kernel/kapplication.cpp:311
#15 0x00007fc7a264ccdc in QCoreApplication::notifyInternal (this=0x7fffb5adfd10, receiver=0x27e4930, event=0x7fffb5adf8e0) at kernel/qcoreapplication.cpp:732
#16 0x00007fc7a267c6f2 in sendEvent (this=0x2302300) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#17 QTimerInfoList::activateTimers (this=0x2302300) at kernel/qeventdispatcher_unix.cpp:602
#18 0x00007fc7a267c82c in QEventDispatcherUNIX::processEvents (this=0x22dbc20, flags=) at kernel/qeventdispatcher_unix.cpp:923
#19 0x00007fc7a1a67c2f in QEventDispatcherX11::processEvents (this=<value optimized out>, flags=) at kernel/qeventdispatcher_x11.cpp:152
#20 0x00007fc7a264ba02 in QEventLoop::processEvents (this=<value optimized out>, flags=) at kernel/qeventloop.cpp:149
#21 0x00007fc7a264bdec in QEventLoop::exec (this=0x7fffb5adfc10, flags=) at kernel/qeventloop.cpp:201
#22 0x00007fc7a264febb in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1009
#23 0x00007fc7a65fa643 in kdemain (argc=<value optimized out>, argv=<value optimized out>) at ../../kwin/main.cpp:542
#24 0x00007fc7a6238d8e in __libc_start_main (main=<value optimized out>, argc=<value optimized out>, ubp_av=<value optimized out>, init=<value optimized out>, fini=<value optimized out>, rtld_fini=<value optimized out>, stack_end=0x7fffb5ae0398) at libc-start.c:226
#25 0x0000000000400669 in _start ()

Reported using DrKonqi