Application: plasma-desktop (4.11.14)
KDE Platform Version: 4.14.13
Qt Version: 4.8.6
Operating System: Linux 3.13.0-95-generic x86_64
Distribution: Ubuntu 14.04.5 LTS

-- Information about the crash:
I was trying to open one of many firefox winows using the "taskbar" (is that the name?)

-- Backtrace:
Application: Plasma Desktop Shell (plasma-desktop), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7fe4b23ec800 (LWP 2712))]

Thread 4 (Thread 0x7fe48725a700 (LWP 2714)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007fe4ab0a4ffb in ?? () from /usr/lib/x86_64-linux-gnu/libQtScript.so.4
#2  0x00007fe4ab0a5039 in ?? () from /usr/lib/x86_64-linux-gnu/libQtScript.so.4
#3  0x00007fe4a5c1d184 in start_thread (arg=0x7fe48725a700) at pthread_create.c:312
#4  0x00007fe4b1ce037d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Thread 3 (Thread 0x7fe3fced9700 (LWP 2715)):
#0  0x00007fe4a554d61d in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#1  0x00007fe4a554d979 in g_mutex_lock () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fe4a550b699 in g_main_context_prepare () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fe4a550bf03 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007fe4a550c0ec in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007fe4ae8ba7be in QEventDispatcherGlib::processEvents (this=0x7fe3f80008e0, flags=...) at kernel/qeventdispatcher_glib.cpp:436
#6  0x00007fe4ae88c0af in QEventLoop::processEvents (this=this@entry=0x7fe3fced8da0, flags=...) at kernel/qeventloop.cpp:149
#7  0x00007fe4ae88c3a5 in QEventLoop::exec (this=this@entry=0x7fe3fced8da0, flags=...) at kernel/qeventloop.cpp:204
#8  0x00007fe4ae788c5f in QThread::exec (this=this@entry=0x340d370) at thread/qthread.cpp:537
#9  0x00007fe4ae86d823 in QInotifyFileSystemWatcherEngine::run (this=0x340d370) at io/qfilesystemwatcher_inotify.cpp:265
#10 0x00007fe4ae78b32f in QThreadPrivate::start (arg=0x340d370) at thread/qthread_unix.cpp:349
#11 0x00007fe4a5c1d184 in start_thread (arg=0x7fe3fced9700) at pthread_create.c:312
#12 0x00007fe4b1ce037d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Thread 2 (Thread 0x7fe3f7987700 (LWP 2716)):
#0  0x00007fe4b1cd16cd in read () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007fe4a08e5f45 in ?? () from /usr/lib/nvidia-340/tls/libnvidia-tls.so.340.96
#2  0x00007fe4a554cc10 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fe4a550bb14 in g_main_context_check () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007fe4a550bf7b in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007fe4a550c0ec in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#6  0x00007fe4ae8ba7be in QEventDispatcherGlib::processEvents (this=0x7fe3f00008e0, flags=...) at kernel/qeventdispatcher_glib.cpp:436
#7  0x00007fe4ae88c0af in QEventLoop::processEvents (this=this@entry=0x7fe3f7986da0, flags=...) at kernel/qeventloop.cpp:149
#8  0x00007fe4ae88c3a5 in QEventLoop::exec (this=this@entry=0x7fe3f7986da0, flags=...) at kernel/qeventloop.cpp:204
#9  0x00007fe4ae788c5f in QThread::exec (this=this@entry=0x288dc30) at thread/qthread.cpp:537
#10 0x00007fe4ae86d823 in QInotifyFileSystemWatcherEngine::run (this=0x288dc30) at io/qfilesystemwatcher_inotify.cpp:265
#11 0x00007fe4ae78b32f in QThreadPrivate::start (arg=0x288dc30) at thread/qthread_unix.cpp:349
#12 0x00007fe4a5c1d184 in start_thread (arg=0x7fe3f7987700) at pthread_create.c:312
#13 0x00007fe4b1ce037d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

Thread 1 (Thread 0x7fe4b23ec800 (LWP 2712)):
[KCrash Handler]
#6  size (this=0xf2e66ffffff6ae9) at ../../include/QtCore/../../src/corelib/tools/qlist.h:98
#7  size (this=0xf2e66ffffff6ae9) at ../../include/QtCore/../../src/corelib/tools/qlist.h:137
#8  QObjectPrivate::_q_reregisterTimers (this=0xc024830, pointer=0xf2e66ffffff6ae9) at kernel/qobject.cpp:1525
#9  0x00007fe4ae8a6b2a in QObject::qt_static_metacall (_o=<optimized out>, _c=<optimized out>, _id=<optimized out>, _a=<optimized out>) at .moc/release-shared/moc_qobject.cpp:73
#10 0x00007fe4ae8a6c3d in QObject::qt_metacall (this=<optimized out>, _c=<optimized out>, _id=3, _a=<optimized out>) at .moc/release-shared/moc_qobject.cpp:111
#11 0x00007fe4ab117155 in ?? () from /usr/lib/x86_64-linux-gnu/libQtScript.so.4
#12 0x00007fe4ae8a1a78 in QMetaObject::activate (sender=0xc13c8f0, m=<optimized out>, local_signal_index=<optimized out>, argv=argv@entry=0x0) at kernel/qobject.cpp:3569
#13 0x00007fe4ae8a2223 in QMetaObject::activate (sender=<optimized out>, signal_index=<optimized out>, argv=argv@entry=0x0) at kernel/qobject.cpp:3626
#14 0x00007fe4b04d907e in QDeclarativeVMEMetaObject::metaCall (this=0xbd80600, c=QMetaObject::WriteProperty, _id=<optimized out>, a=0x7ffc1ad076e0) at qml/qdeclarativevmemetaobject.cpp:564
#15 0x00007fe4b04f4c37 in QDeclarativePropertyPrivate::write (object=0xc13c8f0, property=..., value=..., context=<optimized out>, flags=...) at qml/qdeclarativeproperty.cpp:1152
#16 0x00007fe4b04f545c in QDeclarativePropertyPrivate::writeValueProperty (this=0xbd60580, value=..., flags=...) at qml/qdeclarativeproperty.cpp:1088
#17 0x00007fe4b04f5512 in QDeclarativePropertyPrivate::write (that=..., value=..., flags=...) at qml/qdeclarativeproperty.cpp:1343
#18 0x00007fe4b04ef277 in QDeclarativeBinding::update (this=0xbef9370, flags=...) at qml/qdeclarativebinding.cpp:427
#19 0x00007fe4b04ee0db in update (this=<optimized out>) at ../../include/QtDeclarative/private/../../../src/declarative/qml/qdeclarativebinding_p.h:208
#20 QDeclarativeBindingPrivate::emitValueChanged (this=<optimized out>) at qml/qdeclarativebinding.cpp:469
#21 0x00007fe4b04ede63 in QDeclarativeExpression::qt_metacall (this=this@entry=0xbef9370, _c=_c@entry=QMetaObject::InvokeMetaMethod, _id=1, _a=0x7ffc1ad07ad0) at .moc/release-shared/moc_qdeclarativeexpression.cpp:93
#22 0x00007fe4b05e4fd0 in QDeclarativeBinding::qt_metacall (this=0xbef9370, _c=QMetaObject::InvokeMetaMethod, _id=<optimized out>, _a=<optimized out>) at .moc/release-shared/moc_qdeclarativebinding_p.cpp:85
#23 0x00007fe4ae8a1a78 in QMetaObject::activate (sender=0xb1cf820, m=<optimized out>, local_signal_index=<optimized out>, argv=0x0) at kernel/qobject.cpp:3569
#24 0x00007fe4b0482334 in QDeclarativeItem::setImplicitWidth (this=this@entry=0xb1cf820, w=<optimized out>) at graphicsitems/qdeclarativeitem.cpp:3469
#25 0x00007fe4884398ae in TextLabel::updateImplicitSize (this=0xb1cf820) at ../../../../../plasma/desktop/applets/tasks/support/textlabel.cpp:95
#26 0x00007fe488439c19 in TextLabel::setText (this=this@entry=0xb1cf820, text=...) at ../../../../../plasma/desktop/applets/tasks/support/textlabel.cpp:69
#27 0x00007fe488433398 in TextLabel::qt_metacall (this=0xb1cf820, _c=QMetaObject::WriteProperty, _id=1, _a=0x7ffc1ad07d70) at moc_textlabel.cpp:109
#28 0x00007fe4b04f4c37 in QDeclarativePropertyPrivate::write (object=0xb1cf820, property=..., value=..., context=<optimized out>, flags=...) at qml/qdeclarativeproperty.cpp:1152
#29 0x00007fe4b04f545c in QDeclarativePropertyPrivate::writeValueProperty (this=0xbd4f2e0, value=..., flags=...) at qml/qdeclarativeproperty.cpp:1088
#30 0x00007fe4b04f5512 in QDeclarativePropertyPrivate::write (that=..., value=..., flags=...) at qml/qdeclarativeproperty.cpp:1343
#31 0x00007fe4b04ef277 in QDeclarativeBinding::update (this=0xbd4f360, flags=...) at qml/qdeclarativebinding.cpp:427
#32 0x00007fe4b04ee0db in update (this=<optimized out>) at ../../include/QtDeclarative/private/../../../src/declarative/qml/qdeclarativebinding_p.h:208
#33 QDeclarativeBindingPrivate::emitValueChanged (this=<optimized out>) at qml/qdeclarativebinding.cpp:469
#34 0x00007fe4b04ede63 in QDeclarativeExpression::qt_metacall (this=this@entry=0xbd4f360, _c=_c@entry=QMetaObject::InvokeMetaMethod, _id=1, _a=0x7ffc1ad08160) at .moc/release-shared/moc_qdeclarativeexpression.cpp:93
#35 0x00007fe4b05e4fd0 in QDeclarativeBinding::qt_metacall (this=0xbd4f360, _c=QMetaObject::InvokeMetaMethod, _id=<optimized out>, _a=<optimized out>) at .moc/release-shared/moc_qdeclarativebinding_p.cpp:85
#36 0x00007fe4ae8a1a78 in QMetaObject::activate (sender=0x9c33870, m=<optimized out>, local_signal_index=<optimized out>, argv=argv@entry=0x0) at kernel/qobject.cpp:3569
#37 0x00007fe4ae8a2223 in QMetaObject::activate (sender=<optimized out>, signal_index=<optimized out>, argv=argv@entry=0x0) at kernel/qobject.cpp:3626
#38 0x00007fe4b042b4c1 in QDeclarativeOpenMetaObject::setValue (this=0xca9b6c0, id=id@entry=4, value=...) at util/qdeclarativeopenmetaobject.cpp:261
#39 0x00007fe4b04b66f2 in setValue (val=..., id=4, this=0x9c33870) at graphicsitems/qdeclarativevisualitemmodel.cpp:469
#40 QDeclarativeVisualDataModel::_q_itemsChanged (this=0x2c7be30, index=0, count=44, roles=...) at graphicsitems/qdeclarativevisualitemmodel.cpp:1226
#41 0x00007fe4b05e17ed in QDeclarativeVisualDataModel::qt_static_metacall (_o=0xc024830, _c=4294929129, _id=3, _a=0x7ffc1ad074e0) at .moc/release-shared/moc_qdeclarativevisualitemmodel_p.cpp:406
#42 0x00007fe4ae8a187a in QMetaObject::activate (sender=sender@entry=0x2b858e0, m=m@entry=0x7fe4aebf16a0 <QAbstractItemModel::staticMetaObject>, local_signal_index=local_signal_index@entry=2, argv=argv@entry=0x0) at kernel/qobject.cpp:3539
#43 0x00007fe4ae8eb5a3 in QAbstractItemModel::layoutChanged (this=this@entry=0x2b858e0) at .moc/release-shared/moc_qabstractitemmodel.cpp:176
#44 0x00007fe4ae886a89 in QAbstractItemModel::endMoveRows (this=0x2b858e0) at kernel/qabstractitemmodel.cpp:2673
#45 0x00007fe4888a7cac in itemMoved (item=<optimized out>, this=<optimized out>) at ../../../libs/taskmanager/tasksmodel.cpp:524
#46 TaskManager::TasksModel::qt_static_metacall (_o=0xc024830, _id=-38167, _a=0x7ffc1ad08700, _c=<optimized out>) at ./tasksmodel.moc:135
#47 0x00007fe4ae8a187a in QMetaObject::activate (sender=sender@entry=0x2b84b70, m=m@entry=0x7fe488ac41e0 <TaskManager::TaskGroup::staticMetaObject>, local_signal_index=local_signal_index@entry=6, argv=argv@entry=0x7ffc1ad08700) at kernel/qobject.cpp:3539
#48 0x00007fe48889aa62 in TaskManager::TaskGroup::itemPositionChanged (this=this@entry=0x2b84b70, _t1=_t1@entry=0xb59aa10) at ./taskgroup.moc:220
#49 0x00007fe48889d659 in TaskManager::TaskGroup::moveItem (this=0x2b84b70, oldIndex=oldIndex@entry=12, newIndex=newIndex@entry=5) at ../../../libs/taskmanager/taskgroup.cpp:707
#50 0x00007fe48887dc9a in TaskManager::AbstractSortingStrategy::check (this=<optimized out>, itemToCheck=<optimized out>) at ../../../libs/taskmanager/abstractsortingstrategy.cpp:148
#51 0x00007fe4888807ee in TaskManager::GroupManagerPrivate::addTask (this=this@entry=0x2b83ba0, task=task@entry=0xb454d70) at ../../../libs/taskmanager/groupmanager.cpp:360
#52 0x00007fe488881141 in TaskManager::GroupManagerPrivate::taskChanged (this=0x2b83ba0, task=0xb454d70, changes=...) at ../../../libs/taskmanager/groupmanager.cpp:589
#53 0x00007fe488884642 in TaskManager::GroupManager::qt_static_metacall (_o=<optimized out>, _id=<optimized out>, _a=<optimized out>, _c=<optimized out>) at ./groupmanager.moc:86
#54 0x00007fe4ae8a187a in QMetaObject::activate (sender=sender@entry=0x2b82bb0, m=m@entry=0x7fe488ac44c0 <TaskManager::TaskManager::staticMetaObject>, local_signal_index=local_signal_index@entry=6, argv=argv@entry=0x7ffc1ad089c0) at kernel/qobject.cpp:3539
#55 0x00007fe4888a3097 in TaskManager::TaskManager::windowChanged (this=this@entry=0x2b82bb0, _t1=0xb454d70, _t2=...) at ./taskmanager.moc:228
#56 0x00007fe4888a322b in TaskManager::TaskManager::taskChanged (this=0x2b82bb0, changes=...) at ../../../libs/taskmanager/taskmanager.cpp:387
#57 0x00007fe4888a52d1 in TaskManager::TaskManager::qt_static_metacall (_o=0xc024830, _id=-38167, _a=0x3, _c=<optimized out>) at ./taskmanager.moc:110
#58 0x00007fe4ae8a187a in QMetaObject::activate (sender=sender@entry=0xb454d70, m=m@entry=0x7fe488ac2060 <TaskManager::Task::staticMetaObject>, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x7ffc1ad08ba0) at kernel/qobject.cpp:3539
#59 0x00007fe4888927f2 in TaskManager::Task::changed (this=this@entry=0xb454d70, _t1=...) at ./task.moc:238
#60 0x00007fe4888928ac in TaskManager::Task::setActive (this=this@entry=0xb454d70, a=a@entry=true) at ../../../libs/taskmanager/task.cpp:179
#61 0x00007fe4888a369c in TaskManager::TaskManager::activeWindowChanged (this=0x2b82bb0, w=<optimized out>) at ../../../libs/taskmanager/taskmanager.cpp:414
#62 0x00007fe4888a525c in TaskManager::TaskManager::qt_static_metacall (_o=0xc024830, _id=-38167, _a=0x3, _c=<optimized out>) at ./taskmanager.moc:105
#63 0x00007fe4ae8a187a in QMetaObject::activate (sender=sender@entry=0x2442060, m=m@entry=0x7fe4af9672a0 <KWindowSystem::staticMetaObject>, local_signal_index=local_signal_index@entry=3, argv=argv@entry=0x7ffc1ad08d80) at kernel/qobject.cpp:3539
#64 0x00007fe4af66dac2 in KWindowSystem::activeWindowChanged (this=this@entry=0x2442060, _t1=56623536) at ./kwindowsystem.moc:156
#65 0x00007fe4af66ed48 in KWindowSystemPrivate::x11Event (this=0x242d790, ev=0x7ffc1ad08eb0) at ../../kdeui/windowmanagement/kwindowsystem_x11.cpp:197
#66 0x00007fe4af573928 in publicX11Event (e=0x7ffc1ad08eb0, this=<optimized out>) at ../../kdeui/kernel/ksystemeventfilter.cpp:43
#67 KSystemEventFilterPrivate::filterEvent (this=0x2468460, message=0x7ffc1ad08eb0) at ../../kdeui/kernel/ksystemeventfilter.cpp:102
#68 0x00007fe4ae87f35e in QAbstractEventDispatcher::filterEvent (this=0xc024830, message=0xf2e66ffffff6ae9, message@entry=0x7ffc1ad08eb0) at kernel/qabstracteventdispatcher.cpp:542
#69 0x00007fe4adcc8a60 in x11EventSourceDispatch (s=0x233cc30, callback=0x0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:143
#70 0x00007fe4a550be04 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#71 0x00007fe4a550c048 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#72 0x00007fe4a550c0ec in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#73 0x00007fe4ae8ba7a1 in QEventDispatcherGlib::processEvents (this=0x22c66f0, flags=...) at kernel/qeventdispatcher_glib.cpp:434
#74 0x00007fe4adcc8be6 in QGuiEventDispatcherGlib::processEvents (this=<optimized out>, flags=...) at kernel/qguieventdispatcher_glib.cpp:204
#75 0x00007fe4ae88c0af in QEventLoop::processEvents (this=this@entry=0x7ffc1ad09280, flags=...) at kernel/qeventloop.cpp:149
#76 0x00007fe4ae88c3a5 in QEventLoop::exec (this=this@entry=0x7ffc1ad09280, flags=...) at kernel/qeventloop.cpp:204
#77 0x00007fe4ae891b79 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1225
#78 0x00007fe4adc2537c in QApplication::exec () at kernel/qapplication.cpp:3828
#79 0x00007fe4b1fe7624 in kdemain (argc=1, argv=0x7ffc1ad094d8) at ../../../../plasma/desktop/shell/main.cpp:126
#80 0x00007fe4b1c07f45 in __libc_start_main (main=0x4006f0 <main(int, char**)>, argc=1, argv=0x7ffc1ad094d8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffc1ad094c8) at libc-start.c:287
#81 0x000000000040071e in _start ()

Reported using DrKonqi