Application: plasma-desktop (0.3)
KDE Platform Version: 4.4.2 (KDE 4.4.2)
Qt Version: 4.6.2
Operating System: Linux 2.6.32-21-generic x86_64
Distribution: Ubuntu lucid (development branch)

-- Information about the crash:
while i'm removing xbar widget, plasma-desktop crashed

The crash can be reproduced some of the time.

 -- Backtrace:
Application: Spazio di lavoro di Plasma (plasma-desktop), signal: Segmentation fault
[Current thread is 1 (Thread 0x7f53f631d7a0 (LWP 8405))]

Thread 3 (Thread 0x7f53ca7a7710 (LWP 8409)):
#0  0x00007f53ebdf400c in g_main_context_query () from /lib/libglib-2.0.so.0
#1  0x00007f53ebdf939c in ?? () from /lib/libglib-2.0.so.0
#2  0x00007f53ebdf98fc in g_main_context_iteration () from /lib/libglib-2.0.so.0
#3  0x00007f53f25b3566 in QEventDispatcherGlib::processEvents (this=0x19d5ca0, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:414
#4  0x00007f53f2588992 in QEventLoop::processEvents (this=<value optimized out>, flags=) at kernel/qeventloop.cpp:149
#5  0x00007f53f2588d6c in QEventLoop::exec (this=0x7f53ca7a6d70, flags=) at kernel/qeventloop.cpp:201
#6  0x00007f53f2492d59 in QThread::exec (this=<value optimized out>) at thread/qthread.cpp:487
#7  0x00007f53f2569178 in QInotifyFileSystemWatcherEngine::run (this=0x17bd6a0) at io/qfilesystemwatcher_inotify.cpp:248
#8  0x00007f53f2495775 in QThreadPrivate::start (arg=0x17bd6a0) at thread/qthread_unix.cpp:248
#9  0x00007f53f22059ca in start_thread (arg=<value optimized out>) at pthread_create.c:300
#10 0x00007f53f5d406dd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#11 0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7f53d1b46710 (LWP 13161)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007f53f0cb8ca6 in ?? () from /usr/lib/libQtWebKit.so.4
#2  0x00007f53f0cb8ce9 in ?? () from /usr/lib/libQtWebKit.so.4
#3  0x00007f53f22059ca in start_thread (arg=<value optimized out>) at pthread_create.c:300
#4  0x00007f53f5d406dd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#5  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f53f631d7a0 (LWP 8405)):
[KCrash Handler]
#5  *__GI___libc_free (mem=0xffffffff) at malloc.c:3709
#6  0x00007f53f2ee08d7 in ~QXRenderTessellator (this=0x5aaa690, __in_chrg=<value optimized out>) at painting/qpaintengine_x11.cpp:251
#7  0x00007f53f2ed5e98 in ~QX11PaintEngine (this=0x5ca9c10, __in_chrg=<value optimized out>) at painting/qpaintengine_x11.cpp:467
#8  0x00007f53f2dcb868 in QX11PixmapData::release (this=0x64cce60) at image/qpixmap_x11.cpp:1243
#9  0x00007f53f2dcc09a in ~QX11PixmapData (this=0x64cce60, __in_chrg=<value optimized out>) at image/qpixmap_x11.cpp:1238
#10 0x00007f53f2db9e69 in ~QExplicitlySharedDataPointer (this=0x63d97f0, __in_chrg=<value optimized out>) at ../../include/QtCore/../../src/corelib/tools/qshareddata.h:159
#11 ~QPixmap (this=0x63d97f0, __in_chrg=<value optimized out>) at image/qpixmap.cpp:323
#12 0x00007f53e67e63b5 in QVector<QPixmap>::free (this=<value optimized out>, x=0x0) at /usr/include/qt4/QtCore/qvector.h:436
#13 0x00007f53e67e63fe in ~QVector (this=0x38de5d0, __in_chrg=<value optimized out>) at /usr/include/qt4/QtCore/qvector.h:119
#14 ~TileSet (this=0x38de5d0, __in_chrg=<value optimized out>) at ../../../kstyles/oxygen/lib/tileset.h:69
#15 0x00007f53e67f0f5c in QCache<unsigned long long, TileSet>::unlink (this=0x13f5de0, akey=<value optimized out>, aobject=0x5d8af40, acost=<value optimized out>)
    at /usr/include/qt4/QtCore/qcache.h:75
#16 QCache<unsigned long long, TileSet>::remove (this=0x13f5de0, akey=<value optimized out>, aobject=0x5d8af40, acost=<value optimized out>) at /usr/include/qt4/QtCore/qcache.h:161
#17 QCache<unsigned long long, TileSet>::insert (this=0x13f5de0, akey=<value optimized out>, aobject=0x5d8af40, acost=<value optimized out>) at /usr/include/qt4/QtCore/qcache.h:183
#18 0x00007f53e67f345e in OxygenStyleHelper::roundCorner (this=0x13f5cc0, color=<value optimized out>, size=5) at ../../../kstyles/oxygen/helper.cpp:598
#19 0x00007f53e682d5ef in OxygenStyle::eventFilter (this=0x1377730, obj=0x7fff4b0e05f0, ev=0x7fff4b0df470) at ../../../kstyles/oxygen/oxygen.cpp:6235
#20 0x00007f53f2589487 in QCoreApplicationPrivate::sendThroughObjectEventFilters (this=<value optimized out>, receiver=0x7fff4b0e05f0, event=0x7fff4b0df470) at kernel/qcoreapplication.cpp:819
#21 0x00007f53f2cd61fc in QApplicationPrivate::notify_helper (this=0x13249a0, receiver=0x7fff4b0e05f0, e=0x7fff4b0df470) at kernel/qapplication.cpp:4296
#22 0x00007f53f2cdc6fb in QApplication::notify (this=0x13085a0, receiver=0x7fff4b0e05f0, e=0x7fff4b0df470) at kernel/qapplication.cpp:4183
#23 0x00007f53f3e82526 in KApplication::notify (this=0x13085a0, receiver=0x7fff4b0e05f0, event=0x7fff4b0df470) at ../../kdeui/kernel/kapplication.cpp:302
#24 0x00007f53f258a06c in QCoreApplication::notifyInternal (this=0x13085a0, receiver=0x7fff4b0e05f0, event=0x7fff4b0df470) at kernel/qcoreapplication.cpp:704
#25 0x00007f53f2d347dd in QCoreApplication::sendSpontaneousEvent (this=0x642e210, pdev=<value optimized out>, rgn=..., offset=<value optimized out>, flags=<value optimized out>, sharedPainter=0x0, 
    backingStore=0x57ec8a0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:218
#26 QWidgetPrivate::drawWidget (this=0x642e210, pdev=<value optimized out>, rgn=..., offset=<value optimized out>, flags=<value optimized out>, sharedPainter=0x0, backingStore=0x57ec8a0)
    at kernel/qwidget.cpp:5339
#27 0x00007f53f2eee8c5 in QWidgetBackingStore::sync (this=0x57ec8a0) at painting/qbackingstore.cpp:1291
#28 0x00007f53f2eeec19 in QWidgetBackingStore::sync (this=0x57ec8a0, exposedWidget=0x7fff4b0e05f0, exposedRegion=...) at painting/qbackingstore.cpp:1096
#29 0x00007f53f2d4f60a in QETWidget::translatePaintEvent (this=0x7fff4b0e05f0, event=<value optimized out>) at kernel/qapplication_x11.cpp:5078
#30 0x00007f53f2d5ac8b in QApplication::x11ProcessEvent (this=<value optimized out>, event=0x7fff4b0e0260) at kernel/qapplication_x11.cpp:3401
#31 0x00007f53f2d86882 in x11EventSourceDispatch (s=0x1328150, callback=<value optimized out>, user_data=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:146
#32 0x00007f53ebdf58c2 in g_main_context_dispatch () from /lib/libglib-2.0.so.0
#33 0x00007f53ebdf9748 in ?? () from /lib/libglib-2.0.so.0
#34 0x00007f53ebdf98fc in g_main_context_iteration () from /lib/libglib-2.0.so.0
#35 0x00007f53f25b3513 in QEventDispatcherGlib::processEvents (this=0x12ee440, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:412
#36 0x00007f53f2d8646e in QGuiEventDispatcherGlib::processEvents (this=0xffffffff, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:204
#37 0x00007f53f2588992 in QEventLoop::processEvents (this=<value optimized out>, flags=) at kernel/qeventloop.cpp:149
#38 0x00007f53f2588d6c in QEventLoop::exec (this=0x7fff4b0e0590, flags=) at kernel/qeventloop.cpp:201
#39 0x00007f53f31144e5 in QMenu::exec (this=0x7fff4b0e05f0, p=<value optimized out>, action=0x0) at widgets/qmenu.cpp:2063
#40 0x00007f53f5889205 in Plasma::ContainmentPrivate::showContextMenu (this=0x1b1bc50, point=<value optimized out>, screenPos=..., includeApplet=true, isMouseEvent=true)
    at ../../plasma/containment.cpp:785
#41 0x00007f53f588933b in Plasma::Containment::contextMenuEvent (this=0x1b23b40, event=0x7fff4b0e0e40) at ../../plasma/containment.cpp:633
#42 0x00007f53f32cf4a6 in QGraphicsItem::sceneEvent (this=0x1b23b50, event=0x0) at graphicsview/qgraphicsitem.cpp:6469
#43 0x00007f53f32e9f03 in QGraphicsScene::contextMenuEvent (this=<value optimized out>, contextMenuEvent=0x7fff4b0e0e40) at graphicsview/qgraphicsscene.cpp:3552
#44 0x00007f53f32fbf14 in QGraphicsScene::event (this=0x131af00, event=0x7fff4b0e0e40) at graphicsview/qgraphicsscene.cpp:3352
#45 0x00007f53f2cd622c in QApplicationPrivate::notify_helper (this=0x13249a0, receiver=0x131af00, e=0x7fff4b0e0e40) at kernel/qapplication.cpp:4300
#46 0x00007f53f2cdc6fb in QApplication::notify (this=0x13085a0, receiver=0x131af00, e=0x7fff4b0e0e40) at kernel/qapplication.cpp:4183
#47 0x00007f53f3e82526 in KApplication::notify (this=0x13085a0, receiver=0x131af00, event=0x7fff4b0e0e40) at ../../kdeui/kernel/kapplication.cpp:302
#48 0x00007f53f258a06c in QCoreApplication::notifyInternal (this=0x13085a0, receiver=0x131af00, event=0x7fff4b0e0e40) at kernel/qcoreapplication.cpp:704
#49 0x00007f53f3315d5c in QCoreApplication::sendEvent (this=0x1321460, event=0x7fff4b0e1730) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#50 QGraphicsView::contextMenuEvent (this=0x1321460, event=0x7fff4b0e1730) at graphicsview/qgraphicsview.cpp:2813
#51 0x00007f53f2d2bf68 in QWidget::event (this=0x1321460, event=0x7fff4b0e1730) at kernel/qwidget.cpp:8165
#52 0x00007f53f30d34e6 in QFrame::event (this=0x1321460, e=0x7fff4b0e1730) at widgets/qframe.cpp:557
#53 0x00007f53f3314f0b in QGraphicsView::viewportEvent (this=0x1321460, event=0x7fff4b0e1730) at graphicsview/qgraphicsview.cpp:2787
#54 0x00007f53f2589487 in QCoreApplicationPrivate::sendThroughObjectEventFilters (this=<value optimized out>, receiver=0x2fcddf0, event=0x7fff4b0e1730) at kernel/qcoreapplication.cpp:819
#55 0x00007f53f2cd61fc in QApplicationPrivate::notify_helper (this=0x13249a0, receiver=0x2fcddf0, e=0x7fff4b0e1730) at kernel/qapplication.cpp:4296
#56 0x00007f53f2cdc8c3 in QApplication::notify (this=0x13085a0, receiver=0x2fcddf0, e=0x7fff4b0e1730) at kernel/qapplication.cpp:3944
#57 0x00007f53f3e82526 in KApplication::notify (this=0x13085a0, receiver=0x2fcddf0, event=0x7fff4b0e1730) at ../../kdeui/kernel/kapplication.cpp:302
#58 0x00007f53f258a06c in QCoreApplication::notifyInternal (this=0x13085a0, receiver=0x2fcddf0, event=0x7fff4b0e1730) at kernel/qcoreapplication.cpp:704
#59 0x00007f53f2d5bfb2 in QETWidget::translateMouseEvent (this=<value optimized out>, event=<value optimized out>) at kernel/qapplication_x11.cpp:4373
#60 0x00007f53f2d5a8ac in QApplication::x11ProcessEvent (this=<value optimized out>, event=0x7fff4b0e2080) at kernel/qapplication_x11.cpp:3501
#61 0x00007f53f2d86882 in x11EventSourceDispatch (s=0x1328150, callback=<value optimized out>, user_data=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:146
#62 0x00007f53ebdf58c2 in g_main_context_dispatch () from /lib/libglib-2.0.so.0
#63 0x00007f53ebdf9748 in ?? () from /lib/libglib-2.0.so.0
#64 0x00007f53ebdf98fc in g_main_context_iteration () from /lib/libglib-2.0.so.0
#65 0x00007f53f25b3513 in QEventDispatcherGlib::processEvents (this=0x12ee440, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:412
#66 0x00007f53f2d8646e in QGuiEventDispatcherGlib::processEvents (this=0xffffffff, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:204
#67 0x00007f53f2588992 in QEventLoop::processEvents (this=<value optimized out>, flags=) at kernel/qeventloop.cpp:149
#68 0x00007f53f2588d6c in QEventLoop::exec (this=0x7fff4b0e23b0, flags=) at kernel/qeventloop.cpp:201
#69 0x00007f53f258caab in QCoreApplication::exec () at kernel/qcoreapplication.cpp:981
#70 0x00007f53f6017fb2 in kdemain (argc=<value optimized out>, argv=<value optimized out>) at ../../../../plasma/desktop/shell/main.cpp:112
#71 0x00007f53f5c78c4d 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=0x7fff4b0e2738) at libc-start.c:226
#72 0x00000000004006c9 in _start ()

Reported using DrKonqi