Application that crashed: plasma-desktop
Version of the application: 0.3
KDE Version: 4.2.96 (KDE 4.2.96 (KDE 4.3 RC2))
Qt Version: 4.5.0
Operating System: Linux 2.6.28-13-generic x86_64
Distribution: Ubuntu 9.04

What I was doing when the application crashed:
Just switching desktops caused plasma to crash and restart. Was the first time after the update to RC2 so reproduction might be complicated.

 -- Backtrace:
Application: Plasma Workspace (kdeinit4), signal: Segmentation fault
[Current thread is 0 (LWP 3933)]

Thread 2 (Thread 0x7f6462b4d950 (LWP 3936)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:261
#1  0x00007f648249f939 in QWaitCondition::wait (this=0x18108b0, mutex=0x18108a8, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:87
#2  0x00007f648131b4cc in QHostInfoAgent::run (this=0x1810890) at kernel/qhostinfo.cpp:260
#3  0x00007f648249e952 in QThreadPrivate::start (arg=0x1810890) at thread/qthread_unix.cpp:189
#4  0x00007f647e31f3ba in start_thread (arg=<value optimized out>) at pthread_create.c:297
#5  0x00007f647ef03fcd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#6  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f6482a63750 (LWP 3933)):
[KCrash Handler]
#5  AbstractTaskItem::basicPreferredSize (this=0x2ce1060) at /build/buildd/kdebase-workspace-4.2.96/plasma/applets/tasks/tasks.h:92
#6  0x00007f646517a256 in TaskItemLayout::preferredColumns (this=0x177fca0) at /build/buildd/kdebase-workspace-4.2.96/plasma/applets/tasks/taskitemlayout.cpp:206
#7  0x00007f646517abac in TaskItemLayout::gridLayoutSize (this=0x177fca0) at /build/buildd/kdebase-workspace-4.2.96/plasma/applets/tasks/taskitemlayout.cpp:222
#8  0x00007f646517ac3b in TaskItemLayout::layoutItems (this=0x737465676469772f) at /build/buildd/kdebase-workspace-4.2.96/plasma/applets/tasks/taskitemlayout.cpp:245
#9  0x00007f646517b7f4 in TaskItemLayout::insert (this=0x177fca0, index=6, item=0x2cafed0) at /build/buildd/kdebase-workspace-4.2.96/plasma/applets/tasks/taskitemlayout.cpp:125
#10 0x00007f646517b9d0 in TaskItemLayout::addTaskItem (this=0x177fca0, item=0x2cafed0) at /build/buildd/kdebase-workspace-4.2.96/plasma/applets/tasks/taskitemlayout.cpp:82
#11 0x00007f6465187498 in TaskGroupItem::itemAdded (this=0x177f350, groupableItem=0x2a16860) at /build/buildd/kdebase-workspace-4.2.96/plasma/applets/tasks/taskgroupitem.cpp:477
#12 0x00007f6465187a8c in TaskGroupItem::qt_metacall (this=0x177f350, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7fff8aa9b490)
    at /build/buildd/kdebase-workspace-4.2.96/obj-x86_64-linux-gnu/plasma/applets/tasks/taskgroupitem.moc:113
#13 0x00007f648259d1f2 in QMetaObject::activate (sender=0x1685e10, from_signal_index=<value optimized out>, to_signal_index=21, argv=0x0) at kernel/qobject.cpp:3069
#14 0x00007f6464f4ccaf in TaskManager::TaskGroup::itemAdded (this=0x737465676469772f, _t1=0x2a16860) at /build/buildd/kdebase-workspace-4.2.96/obj-x86_64-linux-gnu/libs/taskmanager/taskgroup.moc:139
#15 0x00007f6464f4d80b in TaskManager::TaskGroup::add (this=0x1685e10, item=0x2a16860) at /build/buildd/kdebase-workspace-4.2.96/libs/taskmanager/taskgroup.cpp:138
#16 0x00007f6464f3c5d3 in TaskManager::ProgramGroupingStrategy::handleItem (this=0x1ceca70, item=0x2a16860)
    at /build/buildd/kdebase-workspace-4.2.96/libs/taskmanager/strategies/programgroupingstrategy.cpp:154
#17 0x00007f6464f360bd in TaskManager::GroupManagerPrivate::addTask (this=0x14f8770, task={d = 0x7fff8aa9b5f0}) at /build/buildd/kdebase-workspace-4.2.96/libs/taskmanager/groupmanager.cpp:288
#18 0x00007f6464f36df1 in TaskManager::GroupManagerPrivate::actuallyReloadTasks (this=0x14f8770) at /build/buildd/kdebase-workspace-4.2.96/libs/taskmanager/groupmanager.cpp:155
#19 0x00007f6464f38262 in TaskManager::GroupManager::qt_metacall (this=0x14bbf60, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7fff8aa9b760)
    at /build/buildd/kdebase-workspace-4.2.96/obj-x86_64-linux-gnu/libs/taskmanager/groupmanager.moc:108
#20 0x00007f648259d1f2 in QMetaObject::activate (sender=0x14f87d8, from_signal_index=<value optimized out>, to_signal_index=4, argv=0x0) at kernel/qobject.cpp:3069
#21 0x00007f64825974d3 in QObject::event (this=0x14f87d8, e=0x7f647ef5a528) at kernel/qobject.cpp:1082
#22 0x00007f647fb1078d in QApplicationPrivate::notify_helper (this=0x1089d00, receiver=0x14f87d8, e=0x7fff8aa9be10) at kernel/qapplication.cpp:4084
#23 0x00007f647fb1897a in QApplication::notify (this=0x104ae90, receiver=0x14f87d8, e=0x7fff8aa9be10) at kernel/qapplication.cpp:4049
#24 0x00007f6480c5363b in KApplication::notify (this=0x104ae90, receiver=0x14f87d8, event=0x7fff8aa9be10) at /build/buildd/kde4libs-4.2.96/kdeui/kernel/kapplication.cpp:302
#25 0x00007f648258775c in QCoreApplication::notifyInternal (this=0x104ae90, receiver=0x14f87d8, event=0x7fff8aa9be10) at kernel/qcoreapplication.cpp:602
#26 0x00007f64825b47f6 in QTimerInfoList::activateTimers (this=0x108d200) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:213
#27 0x00007f64825b0f0d in timerSourceDispatch (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:164
#28 0x00007f647e56e20a in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#29 0x00007f647e5718e0 in ?? () from /usr/lib/libglib-2.0.so.0
#30 0x00007f647e571a7c in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#31 0x00007f64825b0e6f in QEventDispatcherGlib::processEvents (this=0x1089830, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:323
#32 0x00007f647fba8bef in QGuiEventDispatcherGlib::processEvents (this=0x737465676469772f, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:202
#33 0x00007f6482586002 in QEventLoop::processEvents (this=<value optimized out>, flags={i = -1968586624}) at kernel/qeventloop.cpp:149
#34 0x00007f64825863cd in QEventLoop::exec (this=0x7fff8aa9c0c0, flags={i = -1968586544}) at kernel/qeventloop.cpp:200
#35 0x00007f6482588694 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:880
#36 0x00007f647643d6bb in kdemain (argc=1, argv=0x102f420) at /build/buildd/kdebase-workspace-4.2.96/plasma/shells/desktop/main.cpp:50
#37 0x0000000000407215 in launch (argc=1, _name=0x103e0f8 "/usr/bin/plasma-desktop", args=<value optimized out>, cwd=0x0, envc=0, envs=0x103e118 "", reset_env=false, tty=0x0, avoid_loops=false, 
    startup_id_str=0x40a3c9 "0") at /build/buildd/kde4libs-4.2.96/kinit/kinit.cpp:676
#38 0x0000000000407a38 in handle_launcher_request (sock=7, who=<value optimized out>) at /build/buildd/kde4libs-4.2.96/kinit/kinit.cpp:1168
#39 0x0000000000407fe5 in handle_requests (waitForPid=0) at /build/buildd/kde4libs-4.2.96/kinit/kinit.cpp:1361
#40 0x0000000000408b26 in main (argc=2, argv=0x7fff8aa9cf68, envp=0x7fff8aa9cf80) at /build/buildd/kde4libs-4.2.96/kinit/kinit.cpp:1788

This bug may be a duplicate of or related to bug 200358

Reported using DrKonqi