Application: kwin (4.5.95 (4.6 RC2))
KDE Platform Version: 4.5.95 (4.6 RC2)
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:

Actually, this happened to times. The first time KWin crashed, when I cligged or dragged a window tab. The second time KWin crashed again, when I was reorganizing the windows into groups. Again, the crash occured when I was dragging a window tab.

The crash can be reproduced some of the time.

-- Backtrace:
Application: KWin (kwin), signal: Segmentation fault
[Current thread is 1 (Thread 0x7fbfb5732780 (LWP 7464))]

Thread 3 (Thread 0x7fbf99795700 (LWP 7498)):
#0  0xffffffffff60017b in ?? ()
#1  0x00007fbf99794ad0 in ?? ()
#2  0x00007fff3d779852 in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

Thread 2 (Thread 0x7fbf98f94700 (LWP 7503)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007fbfb3dae334 in QTWTF::TCMalloc_PageHeap::scavengerThread (this=0x7fbfb40b9160) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:2359
#2  0x00007fbfb3dae369 in QTWTF::TCMalloc_PageHeap::runScavengerThread (context=0x7fbfb40c7234) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:1464
#3  0x00007fbfab9d5971 in start_thread (arg=<value optimized out>) at pthread_create.c:304
#4  0x00007fbfb4f9192d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#5  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7fbfb5732780 (LWP 7464)):
[KCrash Handler]
#6  0x00007fbfb441c952 in Plasma::Corona::popupPosition (this=0x1e357f0, item=0x1f2dbe0, s=..., alignment=19) at ../../plasma/corona.cpp:857
#7  0x00007fbfb44ca327 in Plasma::ToolTipManagerPrivate::showToolTip (this=0x17532c0) at ../../plasma/tooltipmanager.cpp:399
#8  0x00007fbfb44ca465 in Plasma::ToolTipManager::qt_metacall (this=0x17bd800, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7fff3d6fc010) at ./tooltipmanager.moc:88
#9  0x00007fbfb12f6b27 in QMetaObject::activate (sender=0x17bd830, m=<value optimized out>, local_signal_index=<value optimized out>, argv=0x40711c0000000000) at kernel/qobject.cpp:3280
#10 0x00007fbfb12f08f9 in QObject::event (this=0x17bd830, e=0x0) at kernel/qobject.cpp:1183
#11 0x00007fbfb0645fdc in QApplicationPrivate::notify_helper (this=0xcda490, receiver=0x17bd830, e=0x7fff3d6fc760) at kernel/qapplication.cpp:4396
#12 0x00007fbfb064baed in QApplication::notify (this=0x7fff3d6fcb90, receiver=0x17bd830, e=0x7fff3d6fc760) at kernel/qapplication.cpp:4277
#13 0x00007fbfb4a76a36 in KApplication::notify (this=0x7fff3d6fcb90, receiver=0x17bd830, event=0x7fff3d6fc760) at ../../kdeui/kernel/kapplication.cpp:311
#14 0x00007fbfb12decdc in QCoreApplication::notifyInternal (this=0x7fff3d6fcb90, receiver=0x17bd830, event=0x7fff3d6fc760) at kernel/qcoreapplication.cpp:732
#15 0x00007fbfb130e6f2 in sendEvent (this=0xcdaea0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#16 QTimerInfoList::activateTimers (this=0xcdaea0) at kernel/qeventdispatcher_unix.cpp:602
#17 0x00007fbfb130e82c in QEventDispatcherUNIX::processEvents (this=0xcb1250, flags=) at kernel/qeventdispatcher_unix.cpp:923
#18 0x00007fbfb06f9c2f in QEventDispatcherX11::processEvents (this=<value optimized out>, flags=) at kernel/qeventdispatcher_x11.cpp:152
#19 0x00007fbfb12dda02 in QEventLoop::processEvents (this=<value optimized out>, flags=) at kernel/qeventloop.cpp:149
#20 0x00007fbfb12dddec in QEventLoop::exec (this=0x7fff3d6fca90, flags=) at kernel/qeventloop.cpp:201
#21 0x00007fbfb12e1ebb in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1009
#22 0x00007fbfb528adf3 in kdemain () from /usr/lib/kde4/libkdeinit/libkdeinit4_kwin.so
#23 0x00007fbfb4ec9d8e 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=0x7fff3d6fd218) at libc-start.c:226
#24 0x0000000000400669 in _start ()

Reported using DrKonqi