Application: plasmashell (5.5.5)

Qt Version: 5.5.1
Operating System: Linux 4.4.0-34-generic x86_64
Distribution: Ubuntu 16.04.1 LTS

-- Information about the crash:
The system started, I've logged in and then clicked on the System Tray widget (in the Panel).

The crash can be reproduced sometimes.

-- Backtrace:
Application: Plasma (plasmashell), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f4266c338c0 (LWP 3686))]

Thread 8 (Thread 0x7f419f9ff700 (LWP 3879)):
#0  0x00007f4261344e8d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007f425e0da39c in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f425e0da4ac in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f4261c71a9b in QEventDispatcherGlib::processEvents (this=0x7f41980008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:420
#4  0x00007f4261c18dea in QEventLoop::exec (this=this@entry=0x7f419f9fecc0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#5  0x00007f4261a358a4 in QThread::exec (this=<optimized out>) at thread/qthread.cpp:503
#6  0x00007f41a1ede7d7 in KCupsConnection::run() () from /usr/lib/x86_64-linux-gnu/libkcupslib.so
#7  0x00007f4261a3a84e in QThreadPrivate::start (arg=0x398e0f0) at thread/qthread_unix.cpp:331
#8  0x00007f4260b276fa in start_thread (arg=0x7f419f9ff700) at pthread_create.c:333
#9  0x00007f4261350b5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 7 (Thread 0x7f4235c40700 (LWP 3726)):
#0  0x00007f425e11eac9 in g_mutex_lock () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#1  0x00007f425e0da35e in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f425e0da4ac in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f4261c71a9b in QEventDispatcherGlib::processEvents (this=0x7f41ac0008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:420
#4  0x00007f4261c18dea in QEventLoop::exec (this=this@entry=0x7f4235c3fc90, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#5  0x00007f4261a358a4 in QThread::exec (this=this@entry=0x128d2f0) at thread/qthread.cpp:503
#6  0x00007f4264c63ed6 in QQuickPixmapReader::run (this=0x128d2f0) at util/qquickpixmapcache.cpp:817
#7  0x00007f4261a3a84e in QThreadPrivate::start (arg=0x128d2f0) at thread/qthread_unix.cpp:331
#8  0x00007f4260b276fa in start_thread (arg=0x7f4235c40700) at pthread_create.c:333
#9  0x00007f4261350b5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 6 (Thread 0x7f423c9c7700 (LWP 3715)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007f4266682bd4 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#2  0x00007f4266682c19 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#3  0x00007f4260b276fa in start_thread (arg=0x7f423c9c7700) at pthread_create.c:333
#4  0x00007f4261350b5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 5 (Thread 0x7f423e336700 (LWP 3714)):
#0  0x00007f4261a32dcf in QBasicAtomicOps<8>::testAndSetRelaxed<QMutexData*> (currentValue=<synthetic pointer>, newValue=0x0, expectedValue=0x1, _q_value=@0xce6948: 0x0) at ../../include/QtCore/../../src/corelib/arch/qatomic_x86.h:259
#1  QGenericAtomicOps<QBasicAtomicOps<8> >::testAndSetRelease<QMutexData*, QMutexData*> (currentValue=<synthetic pointer>, newValue=0x0, expectedValue=<optimized out>, _q_value=@0xce6948: 0x0) at ../../include/QtCore/../../src/corelib/thread/qgenericatomic.h:175
#2  QBasicAtomicPointer<QMutexData>::testAndSetRelease (currentValue=<synthetic pointer>, newValue=0x0, expectedValue=<optimized out>, this=this@entry=0xce6948) at ../../include/QtCore/../../src/corelib/thread/qbasicatomic.h:278
#3  QBasicMutex::fastTryUnlock (current=<synthetic pointer>, this=this@entry=0xce6948) at thread/qmutex.h:85
#4  QMutex::unlock (this=this@entry=0xce6948) at thread/qmutex.cpp:264
#5  0x00007f4261c71031 in QMutexLocker::unlock (this=<synthetic pointer>) at ../../include/QtCore/../../src/corelib/thread/qmutex.h:138
#6  QMutexLocker::~QMutexLocker (this=<synthetic pointer>, __in_chrg=<optimized out>) at ../../include/QtCore/../../src/corelib/thread/qmutex.h:132
#7  QThreadData::canWaitLocked (this=0xce6920) at ../../include/QtCore/5.5.1/QtCore/private/../../../../../src/corelib/thread/qthread_p.h:240
#8  postEventSourcePrepare (s=0x7f42300012d0, timeout=0x7f423e335b24) at kernel/qeventdispatcher_glib.cpp:254
#9  0x00007f425e0d992d in g_main_context_prepare () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#10 0x00007f425e0da2cb in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#11 0x00007f425e0da4ac in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#12 0x00007f4261c71a9b in QEventDispatcherGlib::processEvents (this=0x7f42300008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:420
#13 0x00007f4261c18dea in QEventLoop::exec (this=this@entry=0x7f423e335ce0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#14 0x00007f4261a358a4 in QThread::exec (this=this@entry=0xd19be0) at thread/qthread.cpp:503
#15 0x00007f42642dd3c5 in QQmlThreadPrivate::run (this=0xd19be0) at qml/ftw/qqmlthread.cpp:141
#16 0x00007f4261a3a84e in QThreadPrivate::start (arg=0xd19be0) at thread/qthread_unix.cpp:331
#17 0x00007f4260b276fa in start_thread (arg=0x7f423e336700) at pthread_create.c:333
#18 0x00007f4261350b5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 4 (Thread 0x7f42401da700 (LWP 3709)):
#0  0x00007f42613409cd in read () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007f425e11d740 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f425e0d9e84 in g_main_context_check () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f425e0da340 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f425e0da4ac in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f4261c71a9b in QEventDispatcherGlib::processEvents (this=0x7f42380008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:420
#6  0x00007f4261c18dea in QEventLoop::exec (this=this@entry=0x7f42401d9ce0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#7  0x00007f4261a358a4 in QThread::exec (this=this@entry=0xc694b0) at thread/qthread.cpp:503
#8  0x00007f42642dd3c5 in QQmlThreadPrivate::run (this=0xc694b0) at qml/ftw/qqmlthread.cpp:141
#9  0x00007f4261a3a84e in QThreadPrivate::start (arg=0xc694b0) at thread/qthread_unix.cpp:331
#10 0x00007f4260b276fa in start_thread (arg=0x7f42401da700) at pthread_create.c:333
#11 0x00007f4261350b5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 3 (Thread 0x7f424b5ef700 (LWP 3696)):
#0  0x00007f4261344e8d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007f425e0da39c in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f425e0da4ac in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f4261c71a9b in QEventDispatcherGlib::processEvents (this=0x7f42440008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:420
#4  0x00007f4261c18dea in QEventLoop::exec (this=this@entry=0x7f424b5eece0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:204
#5  0x00007f4261a358a4 in QThread::exec (this=this@entry=0x914260) at thread/qthread.cpp:503
#6  0x00007f42642dd3c5 in QQmlThreadPrivate::run (this=0x914260) at qml/ftw/qqmlthread.cpp:141
#7  0x00007f4261a3a84e in QThreadPrivate::start (arg=0x914260) at thread/qthread_unix.cpp:331
#8  0x00007f4260b276fa in start_thread (arg=0x7f424b5ef700) at pthread_create.c:333
#9  0x00007f4261350b5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 2 (Thread 0x7f4251f53700 (LWP 3687)):
#0  0x00007f4261344e8d in poll () at ../sysdeps/unix/syscall-template.S:84
#1  0x00007f4265409c62 in ?? () from /usr/lib/x86_64-linux-gnu/libxcb.so.1
#2  0x00007f426540b8d7 in xcb_wait_for_event () from /usr/lib/x86_64-linux-gnu/libxcb.so.1
#3  0x00007f42540a1629 in QXcbEventReader::run (this=0x83f770) at qxcbconnection.cpp:1253
#4  0x00007f4261a3a84e in QThreadPrivate::start (arg=0x83f770) at thread/qthread_unix.cpp:331
#5  0x00007f4260b276fa in start_thread (arg=0x7f4251f53700) at pthread_create.c:333
#6  0x00007f4261350b5d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 1 (Thread 0x7f4266c338c0 (LWP 3686)):
[KCrash Handler]
#6  0x00007f425414c658 in vtable for QFontEngineFT () from /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#7  0x00007f4261c23259 in QMetaObject::cast(QObject*) const () at kernel/qmetaobject.cpp:312
#8  0x00007f4264299d2f in qobject_cast<QQmlEngine*> (object=<optimized out>) at /usr/include/x86_64-linux-gnu/qt5/QtCore/qobject.h:518
#9  QQmlPropertyCache::resolve (this=this@entry=0x4684bb0, data=data@entry=0x4685c68) at qml/qqmlpropertycache.cpp:821
#10 0x00007f4264299d94 in QQmlPropertyCache::ensureResolved (this=this@entry=0x4684bb0, p=p@entry=0x4685c68) at qml/qqmlpropertycache.cpp:788
#11 0x00007f4264299fbe in QQmlPropertyCache::findProperty (this=0x4684bb0, it=..., vmemo=<optimized out>, context=<optimized out>) at qml/qqmlpropertycache.cpp:1016
#12 0x00007f426421e14d in QQmlPropertyCache::property<QV4::String*> (context=0x430c240, object=0x368ccc0, key=<synthetic pointer>, this=0x4684bb0) at ../../include/QtQml/5.5.1/QtQml/private/../../../../../src/qml/qml/qqmlpropertycache_p.h:288
#13 QV4::QObjectWrapper::findProperty (this=this@entry=0x7f423d337238, engine=engine@entry=0xce3610, qmlContext=qmlContext@entry=0x430c240, name=0x7f423d337240, revisionMode=revisionMode@entry=QV4::QObjectWrapper::IgnoreRevision, local=local@entry=0x7ffdbe664680) at jsruntime/qv4qobjectwrapper.cpp:251
#14 0x00007f4264224e4e in QV4::QObjectWrapper::getQmlProperty (this=0x7f423d337238, qmlContext=0x430c240, n=<optimized out>, revisionMode=QV4::QObjectWrapper::IgnoreRevision, hasProperty=0x0, includeImports=<optimized out>) at jsruntime/qv4qobjectwrapper.cpp:279
#15 0x00007f426423690e in QV4::Object::get (hasProperty=0x0, name=<optimized out>, this=<optimized out>) at jsruntime/qv4object_p.h:279
#16 QV4::Runtime::getProperty (engine=0xce3610, object=..., nameIndex=<optimized out>) at jsruntime/qv4runtime.cpp:679
#17 0x00007f4234031117 in ?? ()
#18 0x00007f4261cee6e0 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#19 0x0000000000000000 in ?? ()

Reported using DrKonqi