Bug 351097

Summary: akonadi 15.07.80 crashed when the machine was idle
Product: [Frameworks and Libraries] Akonadi Reporter: Nicolas L. <kde>
Component: IMAP resourceAssignee: Christian Mollekopf <chrigi_1>
Status: RESOLVED FIXED    
Severity: crash CC: ab4bd, alain.quincerot_lnx, auxsvr, daniel, denni.granata, h6zb8-kdebugs20120801, jan_braun, kai, kdenis, kdepim-bugs, lacsilva, martin, Samuele.Kaplun, vit, vkrause
Priority: NOR Keywords: drkonqi
Version: unspecified   
Target Milestone: ---   
Platform: Mageia RPMs   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:

Description Nicolas L. 2015-08-08 21:14:15 UTC 
Application: akonadi_imap_resource (4.88.0)

Qt Version: 5.5.0
Operating System: Linux 4.1.3-desktop-1.mga6 x86_64
Distribution: "Mageia 6"

-- Information about the crash:
- What I was doing when the application crashed:
To reproduce the crash, i have to let the machine idle for an 1h or more.

-- Backtrace:
Application: Akonadi Resource (akonadi_imap_resource), signal: Aborted
Using host libthread_db library "/lib64/libthread_db.so.1".
81	T_PSEUDO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS)
[Current thread is 1 (Thread 0x7fdb4eb6b840 (LWP 18031))]

Thread 4 (Thread 0x7fdb49f4e700 (LWP 18032)):
#0  0x00007fdb5b749d1d in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007fdb56c759d2 in _xcb_conn_wait () at /lib64/libxcb.so.1
#2  0x00007fdb56c7742f in xcb_wait_for_event () at /lib64/libxcb.so.1
#3  0x00007fdb4c274679 in QXcbEventReader::run() (this=0x24d4110) at qxcbconnection.cpp:1197
#4  0x00007fdb5bfd8e8f in QThreadPrivate::start(void*) (arg=0x24d4110) at thread/qthread_unix.cpp:331
#5  0x00007fdb570985bd in start_thread (arg=0x7fdb49f4e700) at pthread_create.c:310
#6  0x00007fdb5b7555cd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 3 (Thread 0x7fdb43df9700 (LWP 18038)):
#0  0x00007fdb5b749d1d in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007fdb55c35614 in g_main_context_iterate (priority=2147483647, n_fds=1, fds=0x7fdb3c003020, timeout=-1, context=0x7fdb3c000990) at gmain.c:4103
#2  0x00007fdb55c35614 in g_main_context_iterate (context=context@entry=0x7fdb3c000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at gmain.c:3803
#3  0x00007fdb55c3571c in g_main_context_iteration (context=0x7fdb3c000990, may_block=1) at gmain.c:3869
#4  0x00007fdb5c20978c in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7fdb3c0008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:418
#5  0x00007fdb5c1b21ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7fdb43df8d90, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#6  0x00007fdb5bfd413c in QThread::exec() (this=<optimized out>) at thread/qthread.cpp:503
#7  0x00007fdb5bfd8e8f in QThreadPrivate::start(void*) (arg=0x25db560) at thread/qthread_unix.cpp:331
#8  0x00007fdb570985bd in start_thread (arg=0x7fdb43df9700) at pthread_create.c:310
#9  0x00007fdb5b7555cd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 2 (Thread 0x7fdb435f8700 (LWP 18580)):
#0  0x00007fdb55c34e04 in g_main_context_query (context=context@entry=0x7fdb34002cb0, max_priority=2147483647, timeout=timeout@entry=0x7fdb435f7c6c, fds=fds@entry=0x7fdb34002d70, n_fds=n_fds@entry=2) at gmain.c:3507
#1  0x00007fdb55c3558f in g_main_context_iterate (context=context@entry=0x7fdb34002cb0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at gmain.c:3790
#2  0x00007fdb55c3571c in g_main_context_iteration (context=0x7fdb34002cb0, may_block=1) at gmain.c:3869
#3  0x00007fdb5c20978c in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x7fdb340030f0, flags=...) at kernel/qeventdispatcher_glib.cpp:418
#4  0x00007fdb5c1b21ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7fdb435f7d90, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#5  0x00007fdb5bfd413c in QThread::exec() (this=<optimized out>) at thread/qthread.cpp:503
#6  0x00007fdb5bfd8e8f in QThreadPrivate::start(void*) (arg=0x25fd580) at thread/qthread_unix.cpp:331
#7  0x00007fdb570985bd in start_thread (arg=0x7fdb435f8700) at pthread_create.c:310
#8  0x00007fdb5b7555cd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 1 (Thread 0x7fdb4eb6b840 (LWP 18031)):
[KCrash Handler]
#5  0x00007fdb5b691627 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:55
#6  0x00007fdb5b692dba in __GI_abort () at abort.c:89
#7  0x00007fdb5bc88c0d in __gnu_cxx::__verbose_terminate_handler() () at ../../../../libstdc++-v3/libsupc++/vterminate.cc:95
#8  0x00007fdb5bc86c96 in __cxxabiv1::__terminate(void (*)()) (handler=<optimized out>) at ../../../../libstdc++-v3/libsupc++/eh_terminate.cc:47
#9  0x00007fdb5bc86ce1 in std::terminate() () at ../../../../libstdc++-v3/libsupc++/eh_terminate.cc:57
#10 0x00007fdb5bc86ef8 in __cxxabiv1::__cxa_throw(void*, std::type_info*, void (*)(void*)) (obj=0x25febe0, tinfo=0x7fdb5ab785d0 <typeinfo for Akonadi::ProtocolException>, dest=0x7fdb5a91edc0 <Akonadi::ProtocolException::~ProtocolException()>) at ../../../../libstdc++-v3/libsupc++/eh_throw.cc:87
#11 0x00007fdb5a91fe51 in Akonadi::Protocol::DataStream::waitForData(unsigned int) (this=this@entry=0x7ffda23f3390, size=size@entry=2097152) at /usr/src/debug/akonadi-15.07.80/src/private/datastream_p.cpp:66
#12 0x00007fdb5a937d3e in Akonadi::Protocol::DataStream::operator>>(QString&) (this=0x7ffda23f3390, str=...) at /usr/src/debug/akonadi-15.07.80/src/private/datastream_p_p.h:207
#13 0x00007fdb5a92dc10 in Akonadi::Protocol::deserialize(QIODevice*) (command=..., stream=...) at /usr/src/debug/akonadi-15.07.80/src/private/protocol.cpp:359
#14 0x00007fdb5a92dc10 in Akonadi::Protocol::deserialize(QIODevice*) (device=<optimized out>) at /usr/src/debug/akonadi-15.07.80/src/private/protocol.cpp:627
#15 0x00007fdb5ef4cb6b in Akonadi::SessionPrivate::dataReceived() (this=0x2582650) at /usr/src/debug/kdepimlibs-15.07.80/akonadi/src/core/session.cpp:237
#16 0x00007fdb5c1e1efe in QMetaObject::activate(QObject*, int, int, void**) (sender=<optimized out>, signalOffset=<optimized out>, local_signal_index=<optimized out>, argv=<optimized out>) at kernel/qobject.cpp:3718
#17 0x00007fdb5c1e1efe in QMetaObject::activate(QObject*, int, int, void**) (sender=sender@entry=0x257a258, signalOffset=<optimized out>, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x0) at kernel/qobject.cpp:3718
#18 0x00007fdb5c1e2597 in QMetaObject::activate(QObject*, QMetaObject const*, int, void**) (sender=sender@entry=0x257a258, m=m@entry=0x7fdb5c402980 <QIODevice::staticMetaObject>, local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x0) at kernel/qobject.cpp:3583
#19 0x00007fdb5c25cfd0 in QIODevice::readyRead() (this=this@entry=0x257a258) at .moc/moc_qiodevice.cpp:155
#20 0x00007fdb60b861f0 in QAbstractSocketPrivate::canReadNotification() (this=0x255ab00) at socket/qabstractsocket.cpp:730
#21 0x00007fdb60b92e71 in QReadNotifier::event(QEvent*) (this=<optimized out>, e=<optimized out>) at socket/qnativesocketengine.cpp:1169
#22 0x00007fdb5cb70c1c in QApplicationPrivate::notify_helper(QObject*, QEvent*) (this=0x24bd010, receiver=0x26416b0, e=0x7ffda23f3940) at kernel/qapplication.cpp:3717
#23 0x00007fdb5cb75d90 in QApplication::notify(QObject*, QEvent*) (this=0x7ffda23f3bc0, receiver=0x26416b0, e=0x7ffda23f3940) at kernel/qapplication.cpp:3500
#24 0x00007fdb5c1b482b in QCoreApplication::notifyInternal(QObject*, QEvent*) (this=0x7ffda23f3bc0, receiver=0x26416b0, event=event@entry=0x7ffda23f3940) at kernel/qcoreapplication.cpp:965
#25 0x00007fdb5c209df5 in socketNotifierSourceDispatch(GSource*, GSourceFunc, gpointer) (event=0x7ffda23f3940, receiver=<optimized out>) at ../../src/corelib/kernel/qcoreapplication.h:224
#26 0x00007fdb5c209df5 in socketNotifierSourceDispatch(GSource*, GSourceFunc, gpointer) (source=0x24fd920) at kernel/qeventdispatcher_glib.cpp:101
#27 0x00007fdb55c353cd in g_main_context_dispatch (context=0x7fdb440016f0) at gmain.c:3122
#28 0x00007fdb55c353cd in g_main_context_dispatch (context=context@entry=0x7fdb440016f0) at gmain.c:3737
#29 0x00007fdb55c35678 in g_main_context_iterate (context=context@entry=0x7fdb440016f0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at gmain.c:3808
#30 0x00007fdb55c3571c in g_main_context_iteration (context=0x7fdb440016f0, may_block=1) at gmain.c:3869
#31 0x00007fdb5c20978c in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x24f2280, flags=...) at kernel/qeventdispatcher_glib.cpp:418
#32 0x00007fdb5c1b21ca in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7ffda23f3b40, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#33 0x00007fdb5c1b9e11 in QCoreApplication::exec() () at kernel/qcoreapplication.cpp:1229
#34 0x00007fdb5c5708cc in QGuiApplication::exec() () at kernel/qguiapplication.cpp:1528
#35 0x00007fdb5cb6cef5 in QApplication::exec() () at kernel/qapplication.cpp:2977
#36 0x00007fdb5f2b3aea in Akonadi::ResourceBase::init(Akonadi::ResourceBase*) (r=0x251a330) at /usr/src/debug/kdepimlibs-15.07.80/akonadi/src/agentbase/resourcebase.cpp:599
#37 0x000000000043cc73 in int Akonadi::ResourceBase::init<ImapResource>(int, char**) ()
#38 0x00007fdb5b67dfd0 in __libc_start_main (main=0x43cad0 <main>, argc=3, argv=0x7ffda23f3cd8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffda23f3cc8) at libc-start.c:289
#39 0x000000000043cb37 in _start ()

Possible duplicates by query: bug 350831, bug 349113, bug 347814, bug 347785, bug 347595.

Reported using DrKonqi
Comment 1 Weng Xuetian 2015-10-20 21:07:17 UTC 
*** Bug 353304 has been marked as a duplicate of this bug. ***
Comment 2 Weng Xuetian 2015-10-20 21:07:54 UTC 
*** Bug 352495 has been marked as a duplicate of this bug. ***
Comment 3 Weng Xuetian 2015-10-21 19:51:47 UTC 
Git commit 5f272998af641c40761cbe43c76d10b7a00e851c by Weng Xuetian.
Committed on 21/10/2015 at 19:49.
Pushed by xuetianweng into branch 'master'.

Catch the exception when Akonadi::Protocol::deserialize fails.
REVIEW: 125731

M  +6    -1    akonadi/src/core/connectionthread.cpp

http://commits.kde.org/kdepimlibs/5f272998af641c40761cbe43c76d10b7a00e851c
Comment 4 George L. Emigh 2015-11-03 00:09:02 UTC 
My crash looks like bug 353304 "Akonadi crashes while indexing IMAP resource" which is marked as a duplicate.

Application: Kontact (kontact), signal: Aborted
Using host libthread_db library "/lib64/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f83d5cb27c0 (LWP 14827))]

Thread 9 (Thread 0x7f83d1d57700 (LWP 14829)):
#0  0x00007f83eaf1dccf in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1  0x00007f83ef3dade4 in WTF::TCMalloc_PageHeap::scavengerThread (this=<optimized out>) at wtf/FastMalloc.cpp:2821
#2  0x00007f83ef3dae09 in WTF::TCMalloc_PageHeap::runScavengerThread (context=<optimized out>) at wtf/FastMalloc.cpp:1989
#3  0x00007f83eaf184c6 in start_thread () from /lib64/libpthread.so.0
#4  0x00007f83f02e686d in clone () from /lib64/libc.so.6

Thread 8 (Thread 0x7f838adc8700 (LWP 14830)):
#0  0x00007f83e8f35e69 in g_mutex_lock (mutex=mutex@entry=0x7f8384000990) at /var/tmp/portage/dev-libs/glib-2.44.1/work/glib-2.44.1/glib/gthread-posix.c:1336
#1  0x00007f83e8eeead7 in g_main_context_prepare (context=context@entry=0x7f8384000990, priority=priority@entry=0x7f838adc7ca0) at /var/tmp/portage/dev-libs/glib-2.44.1/work/glib-2.44.1/glib/gmain.c:3412
#2  0x00007f83e8eef4e8 in g_main_context_iterate (context=context@entry=0x7f8384000990, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.44.1/work/glib-2.44.1/glib/gmain.c:3788
#3  0x00007f83e8eef6ec in g_main_context_iteration (context=0x7f8384000990, may_block=1) at /var/tmp/portage/dev-libs/glib-2.44.1/work/glib-2.44.1/glib/gmain.c:3869
#4  0x00007f83f0d6e0eb in QEventDispatcherGlib::processEvents (this=0x7f83840008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:418
#5  0x00007f83f0d1ddaa in QEventLoop::exec (this=this@entry=0x7f838adc7e00, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#6  0x00007f83f0b62cf6 in QThread::exec (this=<optimized out>) at thread/qthread.cpp:503
#7  0x00007f83f0b67912 in QThreadPrivate::start (arg=0x1227950) at thread/qthread_unix.cpp:331
#8  0x00007f83eaf184c6 in start_thread () from /lib64/libpthread.so.0
#9  0x00007f83f02e686d in clone () from /lib64/libc.so.6

Thread 7 (Thread 0x7f837ebd2700 (LWP 14832)):
#0  0x00007f83eaf1dccf in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1  0x00007f8389fa980b in cnd_wait (mtx=0x12e1ab8, cond=0x12e1ae0) at /var/tmp/portage/media-libs/mesa-11.0.4/work/mesa-11.0.4/include/c11/threads_posix.h:154
#2  pipe_semaphore_wait (sema=0x12e1ab8) at /var/tmp/portage/media-libs/mesa-11.0.4/work/mesa-11.0.4/src/gallium/auxiliary/os/os_thread.h:259
#3  radeon_drm_cs_emit_ioctl (param=param@entry=0x12e1770) at /var/tmp/portage/media-libs/mesa-11.0.4/work/mesa-11.0.4/src/gallium/winsys/radeon/drm/radeon_drm_winsys.c:644
#4  0x00007f8389fa8e17 in impl_thrd_routine (p=<optimized out>) at /var/tmp/portage/media-libs/mesa-11.0.4/work/mesa-11.0.4/include/c11/threads_posix.h:87
#5  0x00007f83eaf184c6 in start_thread () from /lib64/libpthread.so.0
#6  0x00007f83f02e686d in clone () from /lib64/libc.so.6

Thread 6 (Thread 0x7f837e051700 (LWP 14833)):
#0  0x00007f83eaf1dccf in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1  0x00007f83ef0b7e75 in JSC::BlockAllocator::blockFreeingThreadMain (this=0x7f83d14b9058) at heap/BlockAllocator.cpp:139
#2  0x00007f83ef40f3b1 in WTF::wtfThreadEntryPoint (param=0x7f83d145c1b0) at wtf/ThreadingPthreads.cpp:195
#3  0x00007f83eaf184c6 in start_thread () from /lib64/libpthread.so.0
#4  0x00007f83f02e686d in clone () from /lib64/libc.so.6

Thread 5 (Thread 0x7f837d850700 (LWP 14834)):
#0  0x00007f83eaf1dccf in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1  0x00007f83ef0b8fab in waitForNextPhase (this=0x13af5d0) at heap/GCThread.cpp:81
#2  JSC::GCThread::gcThreadMain (this=0x13af5d0) at heap/GCThread.cpp:99
#3  0x00007f83ef40f3b1 in WTF::wtfThreadEntryPoint (param=0x7f83d145c140) at wtf/ThreadingPthreads.cpp:195
#4  0x00007f83eaf184c6 in start_thread () from /lib64/libpthread.so.0
#5  0x00007f83f02e686d in clone () from /lib64/libc.so.6

Thread 4 (Thread 0x7f837d04f700 (LWP 14835)):
#0  0x00007f83eaf1dccf in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1  0x00007f83ef0b8fab in waitForNextPhase (this=0x13ada60) at heap/GCThread.cpp:81
#2  JSC::GCThread::gcThreadMain (this=0x13ada60) at heap/GCThread.cpp:99
#3  0x00007f83ef40f3b1 in WTF::wtfThreadEntryPoint (param=0x7f83d145c080) at wtf/ThreadingPthreads.cpp:195
#4  0x00007f83eaf184c6 in start_thread () from /lib64/libpthread.so.0
#5  0x00007f83f02e686d in clone () from /lib64/libc.so.6

Thread 3 (Thread 0x7f837c84e700 (LWP 14836)):
#0  0x00007f83eaf1dccf in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1  0x00007f83ef0b8fab in waitForNextPhase (this=0x13ab290) at heap/GCThread.cpp:81
#2  JSC::GCThread::gcThreadMain (this=0x13ab290) at heap/GCThread.cpp:99
#3  0x00007f83ef40f3b1 in WTF::wtfThreadEntryPoint (param=0x7f83d145c3e0) at wtf/ThreadingPthreads.cpp:195
#4  0x00007f83eaf184c6 in start_thread () from /lib64/libpthread.so.0
#5  0x00007f83f02e686d in clone () from /lib64/libc.so.6

Thread 2 (Thread 0x7f83427fc700 (LWP 14944)):
#0  0x00007f83eaf1dccf in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1  0x00007f836db3f984 in QTWTF::TCMalloc_PageHeap::scavengerThread (this=0x7f836dc0e140 <QTWTF::pageheap_memory>) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:2359
#2  0x00007f836db3f9c9 in QTWTF::TCMalloc_PageHeap::runScavengerThread (context=<optimized out>) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:1464
#3  0x00007f83eaf184c6 in start_thread () from /lib64/libpthread.so.0
#4  0x00007f83f02e686d in clone () from /lib64/libc.so.6

Thread 1 (Thread 0x7f83d5cb27c0 (LWP 14827)):
[KCrash Handler]
#6  0x00007f83f022f897 in raise () from /lib64/libc.so.6
#7  0x00007f83f0230cbd in abort () from /lib64/libc.so.6
#8  0x00007f83f0813745 in __gnu_cxx::__verbose_terminate_handler () at /var/tmp/portage/sys-devel/gcc-4.9.3/work/gcc-4.9.3/libstdc++-v3/libsupc++/vterminate.cc:95
#9  0x00007f83f0811426 in __cxxabiv1::__terminate (handler=<optimized out>) at /var/tmp/portage/sys-devel/gcc-4.9.3/work/gcc-4.9.3/libstdc++-v3/libsupc++/eh_terminate.cc:47
#10 0x00007f83f0811491 in std::terminate () at /var/tmp/portage/sys-devel/gcc-4.9.3/work/gcc-4.9.3/libstdc++-v3/libsupc++/eh_terminate.cc:57
#11 0x00007f83f08116c7 in __cxxabiv1::__cxa_throw (obj=0xfb3ed10, tinfo=0x7f83e2b635d0 <typeinfo for Akonadi::ProtocolException>, dest=0x7f83e2907140 <Akonadi::ProtocolException::~ProtocolException()>) at /var/tmp/portage/sys-devel/gcc-4.9.3/work/gcc-4.9.3/libstdc++-v3/libsupc++/eh_throw.cc:87
#12 0x00007f83e2908041 in Akonadi::Protocol::DataStream::waitForData (this=this@entry=0x7ffe366d0770, size=size@entry=2097152) at /var/tmp/portage/kde-apps/akonadi-15.08.2/work/akonadi-15.08.2/src/private/datastream_p.cpp:64
#13 0x00007f83e2925b4d in Akonadi::Protocol::DataStream::operator>> (this=0x7ffe366d0770, str=...) at /var/tmp/portage/kde-apps/akonadi-15.08.2/work/akonadi-15.08.2/src/private/datastream_p_p.h:205
#14 0x00007f83e2919354 in Akonadi::Protocol::deserialize (device=<optimized out>) at /var/tmp/portage/kde-apps/akonadi-15.08.2/work/akonadi-15.08.2/src/private/protocol.cpp:627
#15 0x00007f83ebfaaf1b in Akonadi::SessionPrivate::dataReceived (this=0x15f6d30) at /tmp/portage/kde-apps/kdepimlibs-15.08.2/work/kdepimlibs-15.08.2/akonadi/src/core/session.cpp:239
#16 0x00007f83f0d4871c in QMetaObject::activate (sender=0x1614d30, signalOffset=<optimized out>, local_signal_index=<optimized out>, argv=0x0) at kernel/qobject.cpp:3713
#17 0x00007f83f0d4871c in QMetaObject::activate (sender=sender@entry=0x15fbfc8, signalOffset=<optimized out>, local_signal_index=local_signal_index@entry=32643, argv=0x0, argv@entry=0x7ffe366d1220) at kernel/qobject.cpp:3713
#18 0x00007f83f0d48f2f in QMetaObject::activate (sender=sender@entry=0x15fbfc8, m=m@entry=0x7f83f0f55000 <QIODevice::staticMetaObject>, local_signal_index=32643, local_signal_index@entry=0, argv=0x7ffe366d1220, argv@entry=0x0) at kernel/qobject.cpp:3578
#19 0x00007f83f0dbbb70 in QIODevice::readyRead (this=this@entry=0x15fbfc8) at .moc/moc_qiodevice.cpp:155
#20 0x00007f83ebe0e070 in QAbstractSocketPrivate::canReadNotification (this=0x1611730) at socket/qabstractsocket.cpp:730
#21 0x00007f83ebe1c021 in QReadNotifier::event (this=<optimized out>, e=<optimized out>) at socket/qnativesocketengine.cpp:1169
#22 0x00007f83f15b1d0c in QApplicationPrivate::notify_helper (this=this@entry=0x10baa10, receiver=receiver@entry=0x15081d0, e=e@entry=0x7ffe366d0d60) at kernel/qapplication.cpp:3716
#23 0x00007f83f15b7418 in QApplication::notify (this=0x7ffe366d1220, receiver=0x15081d0, e=0x7ffe366d0d60) at kernel/qapplication.cpp:3499
#24 0x00007f83f0d1f2ac in QCoreApplication::notifyInternal (this=0x7ffe366d1220, receiver=0x15081d0, event=event@entry=0x7ffe366d0d60) at kernel/qcoreapplication.cpp:965
#25 0x00007f83f0d6eaee in sendEvent (event=0x7ffe366d0d60, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:224
#26 socketNotifierSourceDispatch (source=0x11023c0) at kernel/qeventdispatcher_glib.cpp:101
#27 0x00007f83e8eef344 in g_main_dispatch (context=0x7f83cc0016f0) at /var/tmp/portage/dev-libs/glib-2.44.1/work/glib-2.44.1/glib/gmain.c:3122
#28 g_main_context_dispatch (context=context@entry=0x7f83cc0016f0) at /var/tmp/portage/dev-libs/glib-2.44.1/work/glib-2.44.1/glib/gmain.c:3737
#29 0x00007f83e8eef625 in g_main_context_iterate (context=context@entry=0x7f83cc0016f0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at /var/tmp/portage/dev-libs/glib-2.44.1/work/glib-2.44.1/glib/gmain.c:3808
#30 0x00007f83e8eef6ec in g_main_context_iteration (context=0x7f83cc0016f0, may_block=1) at /var/tmp/portage/dev-libs/glib-2.44.1/work/glib-2.44.1/glib/gmain.c:3869
#31 0x00007f83f0d6e0eb in QEventDispatcherGlib::processEvents (this=0x1116710, flags=...) at kernel/qeventdispatcher_glib.cpp:418
#32 0x00007f83f0d1ddaa in QEventLoop::exec (this=this@entry=0x7ffe366d0f90, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#33 0x00007f83f0d2543c in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1229
#34 0x00007f83f104a6bc in QGuiApplication::exec () at kernel/qguiapplication.cpp:1527
#35 0x00007f83f15ad7a5 in QApplication::exec () at kernel/qapplication.cpp:2976
#36 0x0000000000404bb5 in main (argc=1, argv=0x7ffe366d1378) at /var/tmp/portage/kde-apps/kdepim-15.08.2/work/kdepim-15.08.2/kontact/src/main.cpp:220
Comment 5 Denis Kurz 2016-09-06 21:11:44 UTC 
*** Bug 351515 has been marked as a duplicate of this bug. ***
Comment 6 Denis Kurz 2016-09-06 21:11:49 UTC 
*** Bug 355239 has been marked as a duplicate of this bug. ***
Comment 7 Denis Kurz 2016-09-06 21:11:57 UTC 
*** Bug 354224 has been marked as a duplicate of this bug. ***
Comment 8 Denis Kurz 2016-09-06 21:12:03 UTC 
*** Bug 352684 has been marked as a duplicate of this bug. ***
Comment 9 Denis Kurz 2016-09-06 21:12:10 UTC 
*** Bug 355473 has been marked as a duplicate of this bug. ***
Comment 10 Denis Kurz 2016-09-06 21:12:22 UTC 
*** Bug 357364 has been marked as a duplicate of this bug. ***
Comment 11 Denis Kurz 2016-09-06 21:12:30 UTC 
*** Bug 357732 has been marked as a duplicate of this bug. ***
Comment 12 Denis Kurz 2016-09-06 21:12:35 UTC 
*** Bug 359090 has been marked as a duplicate of this bug. ***
Comment 13 Denis Kurz 2016-09-06 21:12:43 UTC 
*** Bug 359304 has been marked as a duplicate of this bug. ***
Comment 14 Denis Kurz 2016-09-06 21:18:07 UTC 
All reports of duplicates of this bug stopped shortly after Weng's proposed fix in comment 3. This fix was included in version 15.12.0 (and even 15.11.80), and the duplicates of this bug reports filed after the release of 15.12.0 were still filed against 15.08.* (when the version was provided).

It seems quite obvious that Weng's fix actually solved the problem, so I close here. I gladly reopen if someone stil sees this in version 15.12.0 or later.