Application: kontact (4.14.6)
KDE Platform Version: 4.14.6
Qt Version: 4.8.6
Operating System: Linux 3.19.0-18-generic x86_64
Distribution: Ubuntu 15.04

-- Information about the crash:
Kmail/Kontact crashes right after changing the layout of the folger view from short to long and vice versa.

The crash can be reproduced every time.

-- Backtrace:
Application: Kontact (kontact), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7ff364970800 (LWP 3034))]

Thread 6 (Thread 0x7ff344c0d700 (LWP 3036)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007ff35f60681d in ?? () from /usr/lib/x86_64-linux-gnu/libQtWebKit.so.4
#2  0x00007ff35f606859 in ?? () from /usr/lib/x86_64-linux-gnu/libQtWebKit.so.4
#3  0x00007ff35bd046aa in start_thread (arg=0x7ff344c0d700) at pthread_create.c:333
#4  0x00007ff361e44eed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 5 (Thread 0x7ff3042f2700 (LWP 3037)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007ff35f34720d in ?? () from /usr/lib/x86_64-linux-gnu/libQtWebKit.so.4
#2  0x00007ff35f635fd6 in ?? () from /usr/lib/x86_64-linux-gnu/libQtWebKit.so.4
#3  0x00007ff35bd046aa in start_thread (arg=0x7ff3042f2700) at pthread_create.c:333
#4  0x00007ff361e44eed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 4 (Thread 0x7ff2f3395700 (LWP 3045)):
#0  0x00007ff361e398dd in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007ff35b81eebc in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007ff35b81efcc in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007ff3625cd82e in QEventDispatcherGlib::processEvents (this=0x7ff2ec0008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:452
#4  0x00007ff36259ccd1 in QEventLoop::processEvents (this=this@entry=0x7ff2f3394d80, flags=...) at kernel/qeventloop.cpp:149
#5  0x00007ff36259d035 in QEventLoop::exec (this=this@entry=0x7ff2f3394d80, flags=...) at kernel/qeventloop.cpp:204
#6  0x00007ff362490e89 in QThread::exec (this=this@entry=0x22b1b90) at thread/qthread.cpp:538
#7  0x00007ff36257d443 in QInotifyFileSystemWatcherEngine::run (this=0x22b1b90) at io/qfilesystemwatcher_inotify.cpp:265
#8  0x00007ff3624936ff in QThreadPrivate::start (arg=0x22b1b90) at thread/qthread_unix.cpp:349
#9  0x00007ff35bd046aa in start_thread (arg=0x7ff2f3395700) at pthread_create.c:333
#10 0x00007ff361e44eed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 3 (Thread 0x7ff2f2b94700 (LWP 3046)):
#0  0x00007ff35b863789 in g_mutex_lock () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#1  0x00007ff35b81e8cc in g_main_context_check () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007ff35b81ee60 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007ff35b81efcc in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007ff3625cd82e in QEventDispatcherGlib::processEvents (this=0x7ff2e40008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:452
#5  0x00007ff36259ccd1 in QEventLoop::processEvents (this=this@entry=0x7ff2f2b93dd0, flags=...) at kernel/qeventloop.cpp:149
#6  0x00007ff36259d035 in QEventLoop::exec (this=this@entry=0x7ff2f2b93dd0, flags=...) at kernel/qeventloop.cpp:204
#7  0x00007ff362490e89 in QThread::exec (this=<optimized out>) at thread/qthread.cpp:538
#8  0x00007ff3624936ff in QThreadPrivate::start (arg=0x193a920) at thread/qthread_unix.cpp:349
#9  0x00007ff35bd046aa in start_thread (arg=0x7ff2f2b94700) at pthread_create.c:333
#10 0x00007ff361e44eed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 2 (Thread 0x7ff2df9aa700 (LWP 5260)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007ff2fb42ea7a in ?? () from /usr/lib/x86_64-linux-gnu/libQtScript.so.4
#2  0x00007ff2fb42eaa9 in ?? () from /usr/lib/x86_64-linux-gnu/libQtScript.so.4
#3  0x00007ff35bd046aa in start_thread (arg=0x7ff2df9aa700) at pthread_create.c:333
#4  0x00007ff361e44eed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 1 (Thread 0x7ff364970800 (LWP 3034)):
[KCrash Handler]
#6  setText (atext=..., this=0x0) at /usr/include/qt4/QtGui/qstandarditemmodel.h:254
#7  CategorySelectWidgetPrivate::slotTagsChanged (this=0x48eda40, topLeft=..., bottomRight=...) at ../../kaddressbook/categoryselectwidget.cpp:169
#8  0x00007ff3625b319c in QMetaObject::activate (sender=sender@entry=0x4432840, m=m@entry=0x7ff3629038a0 <QAbstractItemModel::staticMetaObject>, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x7ffe3c973a50) at kernel/qobject.cpp:3567
#9  0x00007ff3625ff577 in QAbstractItemModel::dataChanged (this=this@entry=0x4432840, _t1=..., _t2=...) at .moc/release-shared/moc_qabstractitemmodel.cpp:163
#10 0x00007ff360e88fea in Akonadi::TagModelPrivate::monitoredTagChanged (this=0x3bf60c0, tag=...) at ../../akonadi/tagmodel_p.cpp:200
#11 0x00007ff3625b319c in QMetaObject::activate (sender=0x44312c0, m=m@entry=0x7ff3611522c0 <Akonadi::Monitor::staticMetaObject>, local_signal_index=local_signal_index@entry=21, argv=argv@entry=0x7ffe3c973ce0) at kernel/qobject.cpp:3567
#12 0x00007ff360de7c05 in Akonadi::Monitor::tagChanged (this=<optimized out>, _t1=...) at ./moc_monitor.cpp:378
#13 0x00007ff360df33cf in Akonadi::MonitorPrivate::emitTagsNotification (this=this@entry=0x4431b30, msg=..., tags=...) at ../../akonadi/monitor_p.cpp:1011
#14 0x00007ff360df376a in Akonadi::MonitorPrivate::emitNotification (this=0x4431b30, msg=...) at ../../akonadi/monitor_p.cpp:492
#15 0x00007ff360def561 in Akonadi::MonitorPrivate::flushPipeline (this=this@entry=0x4431b30) at ../../akonadi/monitor_p.cpp:718
#16 0x00007ff360def799 in Akonadi::MonitorPrivate::dataAvailable (this=0x4431b30) at ../../akonadi/monitor_p.cpp:727
#17 0x00007ff3625b319c in QMetaObject::activate (sender=sender@entry=0x4431f50, m=m@entry=0x7ff361150180 <Akonadi::EntityCacheBase::staticMetaObject>, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x0) at kernel/qobject.cpp:3567
#18 0x00007ff360d89390 in Akonadi::EntityCacheBase::dataAvailable (this=this@entry=0x4431f50) at ./moc_entitycache_p.cpp:101
#19 0x00007ff360d45b94 in Akonadi::EntityListCache<Akonadi::Tag, Akonadi::TagFetchJob, Akonadi::TagFetchScope>::processResult (this=0x4431f50, job=<optimized out>) at ../../akonadi/entitycache_p.h:501
#20 0x00007ff3625b319c in QMetaObject::activate (sender=sender@entry=0x1d6d610, m=m@entry=0x7ff362dd4f20 <KJob::staticMetaObject>, local_signal_index=local_signal_index@entry=3, argv=argv@entry=0x7ffe3c974220) at kernel/qobject.cpp:3567
#21 0x00007ff362a34362 in KJob::result (this=this@entry=0x1d6d610, _t1=_t1@entry=0x1d6d610) at ./kjob.moc:207
#22 0x00007ff362a343b0 in KJob::emitResult (this=0x1d6d610) at ../../kdecore/jobs/kjob.cpp:318
#23 0x00007ff3625b7891 in QObject::event (this=0x1d6d610, e=<optimized out>) at kernel/qobject.cpp:1222
#24 0x00007ff362faa9bc in QApplicationPrivate::notify_helper (this=this@entry=0x16e1730, receiver=receiver@entry=0x1d6d610, e=e@entry=0x1f65590) at kernel/qapplication.cpp:4570
#25 0x00007ff362fb14d8 in QApplication::notify (this=this@entry=0x7ffe3c974910, receiver=receiver@entry=0x1d6d610, e=e@entry=0x1f65590) at kernel/qapplication.cpp:4356
#26 0x00007ff363d0cb4a in KApplication::notify (this=0x7ffe3c974910, receiver=0x1d6d610, event=0x1f65590) at ../../kdeui/kernel/kapplication.cpp:311
#27 0x00007ff36259e17d in QCoreApplication::notifyInternal (this=0x7ffe3c974910, receiver=receiver@entry=0x1d6d610, event=event@entry=0x1f65590) at kernel/qcoreapplication.cpp:955
#28 0x00007ff3625a1a21 in sendEvent (event=0x1f65590, receiver=0x1d6d610) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:231
#29 QCoreApplicationPrivate::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0, data=0x169f860) at kernel/qcoreapplication.cpp:1579
#30 0x00007ff3625a1eb3 in QCoreApplication::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0) at kernel/qcoreapplication.cpp:1472
#31 0x00007ff3625cd69e in sendPostedEvents () at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:236
#32 postEventSourceDispatch (s=0x16d5460) at kernel/qeventdispatcher_glib.cpp:300
#33 0x00007ff35b81ec3d in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#34 0x00007ff35b81ef20 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#35 0x00007ff35b81efcc in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#36 0x00007ff3625cd80e in QEventDispatcherGlib::processEvents (this=0x167e1b0, flags=...) at kernel/qeventdispatcher_glib.cpp:450
#37 0x00007ff363052c66 in QGuiEventDispatcherGlib::processEvents (this=<optimized out>, flags=...) at kernel/qguieventdispatcher_glib.cpp:204
#38 0x00007ff36259ccd1 in QEventLoop::processEvents (this=this@entry=0x7ffe3c974820, flags=...) at kernel/qeventloop.cpp:149
#39 0x00007ff36259d035 in QEventLoop::exec (this=this@entry=0x7ffe3c974820, flags=...) at kernel/qeventloop.cpp:204
#40 0x00007ff3625a2ab9 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1227
#41 0x00007ff362fa8c1c in QApplication::exec () at kernel/qapplication.cpp:3828
#42 0x0000000000403509 in main (argc=1, argv=0x7ffe3c974a68) at ../../../kontact/src/main.cpp:219

Reported using DrKonqi