Application: kmail (4.14.9)
KDE Platform Version: 4.14.9
Qt Version: 4.8.6
Operating System: Linux 4.3.3-2.gdb72752-default x86_64
Distribution: "openSUSE 13.2 (Harlequin) (x86_64)"

-- Information about the crash:
KMail had hung while emptying the Trash folders on 2 IMAP accounts. It appeared to close normally via File-Quit but crashed with the attached segfault/backtrace when I next attempted to start it (about 30 mins later).

The crash can be reproduced sometimes.

-- Backtrace:
Application: KMail (kmail), signal: Segmentation fault
Using host libthread_db library "/lib64/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f77ab517840 (LWP 12666))]

Thread 5 (Thread 0x7f7784b4b700 (LWP 12671)):
#0  0x00007f77a669705f in pthread_cond_wait@@GLIBC_2.3.2 () at /lib64/libpthread.so.0
#1  0x00007f779bd94686 in WTF::TCMalloc_PageHeap::scavengerThread() () at /usr/lib64/libQtWebKit.so.4
#2  0x00007f779bd946b9 in  () at /usr/lib64/libQtWebKit.so.4
#3  0x00007f77a66930a4 in start_thread () at /lib64/libpthread.so.0
#4  0x00007f77a889208d in clone () at /lib64/libc.so.6

Thread 4 (Thread 0x7f777f998700 (LWP 12672)):
#0  0x00007f77a669705f in pthread_cond_wait@@GLIBC_2.3.2 () at /lib64/libpthread.so.0
#1  0x00007f779bb06e7d in JSC::BlockAllocator::blockFreeingThreadMain() () at /usr/lib64/libQtWebKit.so.4
#2  0x00007f779bdbc1e6 in WTF::wtfThreadEntryPoint(void*) () at /usr/lib64/libQtWebKit.so.4
#3  0x00007f77a66930a4 in start_thread () at /lib64/libpthread.so.0
#4  0x00007f77a889208d in clone () at /lib64/libc.so.6

Thread 3 (Thread 0x7f777eb87700 (LWP 12673)):
#0  0x00007f77a06028e9 in g_mutex_lock () at /usr/lib64/libglib-2.0.so.0
#1  0x00007f77a05c0299 in g_main_context_prepare () at /usr/lib64/libglib-2.0.so.0
#2  0x00007f77a05c0b03 in  () at /usr/lib64/libglib-2.0.so.0
#3  0x00007f77a05c0cec in g_main_context_iteration () at /usr/lib64/libglib-2.0.so.0
#4  0x00007f77a9ee40de in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib64/libQtCore.so.4
#5  0x00007f77a9eb5e6f in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib64/libQtCore.so.4
#6  0x00007f77a9eb6165 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib64/libQtCore.so.4
#7  0x00007f77a9db30bf in QThread::exec() () at /usr/lib64/libQtCore.so.4
#8  0x00007f77a9db579f in  () at /usr/lib64/libQtCore.so.4
#9  0x00007f77a66930a4 in start_thread () at /lib64/libpthread.so.0
#10 0x00007f77a889208d in clone () at /lib64/libc.so.6

Thread 2 (Thread 0x7f777d0fc700 (LWP 12676)):
#0  0x00007f77a669985a in __lll_unlock_wake () at /lib64/libpthread.so.0
#1  0x00007f77a66965d9 in _L_unlock_554 () at /lib64/libpthread.so.0
#2  0x00007f77a6696516 in __pthread_mutex_unlock_usercnt () at /lib64/libpthread.so.0
#3  0x00007f7793f3af45 in  () at /usr/lib64/libGL.so.1
#4  0x00007f7793f40608 in  () at /usr/lib64/libGL.so.1
#5  0x00007f779147a102 in  () at /usr/lib64/tls/libnvidia-tls.so.358.16
#6  0x00007f77a0601750 in  () at /usr/lib64/libglib-2.0.so.0
#7  0x00007f77a05c0714 in g_main_context_check () at /usr/lib64/libglib-2.0.so.0
#8  0x00007f77a05c0b7b in  () at /usr/lib64/libglib-2.0.so.0
#9  0x00007f77a05c0cec in g_main_context_iteration () at /usr/lib64/libglib-2.0.so.0
#10 0x00007f77a9ee40de in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib64/libQtCore.so.4
#11 0x00007f77a9eb5e6f in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib64/libQtCore.so.4
#12 0x00007f77a9eb6165 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib64/libQtCore.so.4
#13 0x00007f77a9db30bf in QThread::exec() () at /usr/lib64/libQtCore.so.4
#14 0x00007f77a9e97783 in  () at /usr/lib64/libQtCore.so.4
#15 0x00007f77a9db579f in  () at /usr/lib64/libQtCore.so.4
#16 0x00007f77a66930a4 in start_thread () at /lib64/libpthread.so.0
#17 0x00007f77a889208d in clone () at /lib64/libc.so.6

Thread 1 (Thread 0x7f77ab517840 (LWP 12666)):
[KCrash Handler]
#6  0x00007f77a9df8c88 in QString::operator==(QString const&) const () at /usr/lib64/libQtCore.so.4
#7  0x00007f77ab0cee5c in KStatusNotifierItem::setToolTipSubTitle(QString const&) (this=0x1fbbb00, subTitle=...) at /usr/src/debug/kdelibs-4.14.9/kdeui/notifications/kstatusnotifieritem.cpp:419
#8  0x00007f77aa2d703e in  () at /usr/lib64/libkmailprivate.so.4
#9  0x00007f77aa2d6f1d in  () at /usr/lib64/libkmailprivate.so.4
#10 0x00007f77aa2d71f6 in  () at /usr/lib64/libkmailprivate.so.4
#11 0x00007f77aa2dfea5 in KMKernel::toggleSystemTray() () at /usr/lib64/libkmailprivate.so.4
#12 0x00007f77aa30cd8f in KMMainWidget::readConfig() () at /usr/lib64/libkmailprivate.so.4
#13 0x00007f77aa31cab1 in KMMainWidget::KMMainWidget(QWidget*, KXMLGUIClient*, KActionCollection*, KSharedPtr<KSharedConfig>) () at /usr/lib64/libkmailprivate.so.4
#14 0x00007f77aa2cf328 in  () at /usr/lib64/libkmailprivate.so.4
#15 0x00007f77aa2deb9f in KMKernel::openReader(bool) () at /usr/lib64/libkmailprivate.so.4
#16 0x00007f77aa2e2bf8 in KMKernel::action(bool, bool, QString const&, QString const&, QString const&, QString const&, QString const&, KUrl const&, KUrl::List const&, QStringList const&, QString const&, QString const&) () at /usr/lib64/libkmailprivate.so.4
#17 0x00007f77aa2e36bb in KMKernel::handleCommandLine(bool) () at /usr/lib64/libkmailprivate.so.4
#18 0x00000000004035c7 in _start ()

Reported using DrKonqi