Application: plasma-desktop (4.11.14)
KDE Platform Version: 4.14.3
Qt Version: 4.8.6
Operating System: Linux 3.17.4-301.fc21.x86_64 x86_64
Distribution (Platform): Fedora RPMs

-- Information about the crash:
- What I was doing when the application crashed: trying to move a widget (calculator) from the panel tool box to the panel. It was the default panel, not one I created. I retried a few more times in a short laps of time (5 minutes), it crashed (see unuasual behavor) every time. I had a few other programs running : konqueror, maybe dolphin, the updates...
I tried a bit later, (1/2 hour ?) an it worked fine.

- Unusual behavior I noticed: The panel bar actualy vanished everytime y let go the click, before held to move the widget. The hole graphics seemed to refresh.

The crash can be reproduced every time.

-- Backtrace:
Application: Plasma Desktop Shell (plasma-desktop), signal: Segmentation fault
Using host libthread_db library "/lib64/libthread_db.so.1".
[Current thread is 1 (Thread 0x7fd04fcfd880 (LWP 1503))]

Thread 3 (Thread 0x7fd0228c0700 (LWP 1506)):
#0  0x00007fd04e2cc590 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1  0x00007fd037b4b41a in QTWTF::TCMalloc_PageHeap::scavengerThread() () from /lib64/libQtScript.so.4
#2  0x00007fd037b4b449 in QTWTF::TCMalloc_PageHeap::runScavengerThread(void*) () from /lib64/libQtScript.so.4
#3  0x00007fd04e2c752a in start_thread () from /lib64/libpthread.so.0
#4  0x00007fd04c89077d in clone () from /lib64/libc.so.6

Thread 2 (Thread 0x7fcf9bf65700 (LWP 1507)):
#0  0x00007fd04c8851dd in poll () from /lib64/libc.so.6
#1  0x00007fd048f70e24 in g_main_context_iterate.isra () from /lib64/libglib-2.0.so.0
#2  0x00007fd048f70f3c in g_main_context_iteration () from /lib64/libglib-2.0.so.0
#3  0x00007fd04e6906be in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib64/libQtCore.so.4
#4  0x00007fd04e65ff91 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib64/libQtCore.so.4
#5  0x00007fd04e6602f5 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib64/libQtCore.so.4
#6  0x00007fd04e555b69 in QThread::exec() () from /lib64/libQtCore.so.4
#7  0x00007fd04e640b53 in QInotifyFileSystemWatcherEngine::run() () from /lib64/libQtCore.so.4
#8  0x00007fd04e5583cf in QThreadPrivate::start(void*) () from /lib64/libQtCore.so.4
#9  0x00007fd04e2c752a in start_thread () from /lib64/libpthread.so.0
#10 0x00007fd04c89077d in clone () from /lib64/libc.so.6

Thread 1 (Thread 0x7fd04fcfd880 (LWP 1503)):
[KCrash Handler]
#5  0x00000000081b9e60 in ?? ()
#6  0x00007fcf99621870 in DeclarativeMimeData::DeclarativeMimeData(QMimeData const*) () from /usr/lib64/kde4/imports/org/kde/draganddrop/libdraganddropplugin.so
#7  0x00007fcf99621111 in DeclarativeDragDropEvent::DeclarativeDragDropEvent(QGraphicsSceneDragDropEvent*, DeclarativeDropArea*) () from /usr/lib64/kde4/imports/org/kde/draganddrop/libdraganddropplugin.so
#8  0x00007fcf99621284 in DeclarativeDropArea::dragLeaveEvent(QGraphicsSceneDragDropEvent*) () from /usr/lib64/kde4/imports/org/kde/draganddrop/libdraganddropplugin.so
#9  0x00007fd04dd7bc39 in QGraphicsItem::sceneEvent(QEvent*) () from /lib64/libQtGui.so.4
#10 0x00007fd03730f1f4 in QDeclarativeItem::sceneEvent(QEvent*) () from /lib64/libQtDeclarative.so.4
#11 0x00007fd04dda4737 in QGraphicsScenePrivate::sendDragDropEvent(QGraphicsItem*, QGraphicsSceneDragDropEvent*) () from /lib64/libQtGui.so.4
#12 0x00007fd04dda477c in QGraphicsScene::dragLeaveEvent(QGraphicsSceneDragDropEvent*) () from /lib64/libQtGui.so.4
#13 0x00007fd04ddbbc6f in QGraphicsScene::event(QEvent*) () from /lib64/libQtGui.so.4
#14 0x00007fd04d79af6c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /lib64/libQtGui.so.4
#15 0x00007fd04d7a19b8 in QApplication::notify(QObject*, QEvent*) () from /lib64/libQtGui.so.4
#16 0x00007fd04f6c69ea in KApplication::notify(QObject*, QEvent*) () from /lib64/libkdeui.so.5
#17 0x00007fd04e66143d in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /lib64/libQtCore.so.4
#18 0x00007fd04ddd4e88 in QGraphicsView::dragLeaveEvent(QDragLeaveEvent*) () from /lib64/libQtGui.so.4
#19 0x00007fd04d7edfe8 in QWidget::event(QEvent*) () from /lib64/libQtGui.so.4
#20 0x00007fd04dbad29e in QFrame::event(QEvent*) () from /lib64/libQtGui.so.4
#21 0x00007fd04ddd4521 in QGraphicsView::viewportEvent(QEvent*) () from /lib64/libQtGui.so.4
#22 0x00007fd04e6615a6 in QCoreApplicationPrivate::sendThroughObjectEventFilters(QObject*, QEvent*) () from /lib64/libQtCore.so.4
#23 0x00007fd04d79af4c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /lib64/libQtGui.so.4
#24 0x00007fd04d7a351f in QApplication::notify(QObject*, QEvent*) () from /lib64/libQtGui.so.4
#25 0x00007fd04f6c69ea in KApplication::notify(QObject*, QEvent*) () from /lib64/libkdeui.so.5
#26 0x00007fd04e66143d in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /lib64/libQtCore.so.4
#27 0x00007fd04d82457e in QX11Data::xdndHandleLeave(QWidget*, _XEvent const*, bool) () from /lib64/libQtGui.so.4
#28 0x00007fd04d8246c1 in qt_xdnd_send_leave() [clone .part.64] () from /lib64/libQtGui.so.4
#29 0x00007fd04d824aaa in QDragManager::cancel(bool) () from /lib64/libQtGui.so.4
#30 0x00007fd04d7ac84a in QDrag::~QDrag() () from /lib64/libQtGui.so.4
#31 0x00007fd04d7ac869 in QDrag::~QDrag() () from /lib64/libQtGui.so.4
#32 0x00007fd04e678a38 in QObjectPrivate::deleteChildren() () from /lib64/libQtCore.so.4
#33 0x00007fd04d7eda13 in QWidget::~QWidget() () from /lib64/libQtGui.so.4
#34 0x00007fd04d7edd29 in QWidget::~QWidget() () from /lib64/libQtGui.so.4
#35 0x00007fd04e678a38 in QObjectPrivate::deleteChildren() () from /lib64/libQtCore.so.4
#36 0x00007fd04d7eda13 in QWidget::~QWidget() () from /lib64/libQtGui.so.4
#37 0x00007fd04ddca3d9 in QGraphicsView::~QGraphicsView() () from /lib64/libQtGui.so.4
#38 0x00007fd02ddcd938 in ControllerWindow::~ControllerWindow() () from /lib64/libkdeinit4_plasma-desktop.so
#39 0x00007fd02ddcd9a9 in ControllerWindow::~ControllerWindow() () from /lib64/libkdeinit4_plasma-desktop.so
#40 0x00007fd04e67a618 in QObject::event(QEvent*) () from /lib64/libQtCore.so.4
#41 0x00007fd04d7ee503 in QWidget::event(QEvent*) () from /lib64/libQtGui.so.4
#42 0x00007fd04d79af6c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /lib64/libQtGui.so.4
#43 0x00007fd04d7a19b8 in QApplication::notify(QObject*, QEvent*) () from /lib64/libQtGui.so.4
#44 0x00007fd04f6c69ea in KApplication::notify(QObject*, QEvent*) () from /lib64/libkdeui.so.5
#45 0x00007fd04e66143d in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /lib64/libQtCore.so.4
#46 0x00007fd04e664701 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () from /lib64/libQtCore.so.4
#47 0x00007fd04e69052e in postEventSourceDispatch(_GSource*, int (*)(void*), void*) () from /lib64/libQtCore.so.4
#48 0x00007fd048f70aeb in g_main_context_dispatch () from /lib64/libglib-2.0.so.0
#49 0x00007fd048f70e88 in g_main_context_iterate.isra () from /lib64/libglib-2.0.so.0
#50 0x00007fd048f70f3c in g_main_context_iteration () from /lib64/libglib-2.0.so.0
#51 0x00007fd04e69069e in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib64/libQtCore.so.4
#52 0x00007fd04d83e346 in QGuiEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib64/libQtGui.so.4
#53 0x00007fd04e65ff91 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib64/libQtCore.so.4
#54 0x00007fd04e6602f5 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib64/libQtCore.so.4
#55 0x00007fd04d826f84 in QDragManager::drag(QDrag*) () from /lib64/libQtGui.so.4
#56 0x00007fd04d7ac99a in QDrag::exec(QFlags<Qt::DropAction>, Qt::DropAction) () from /lib64/libQtGui.so.4
#57 0x00007fcf99620fc8 in DeclarativeDragArea::mouseMoveEvent(QGraphicsSceneMouseEvent*) () from /usr/lib64/kde4/imports/org/kde/draganddrop/libdraganddropplugin.so
#58 0x00007fcf99621079 in DeclarativeDragArea::sceneEventFilter(QGraphicsItem*, QEvent*) () from /usr/lib64/kde4/imports/org/kde/draganddrop/libdraganddropplugin.so
#59 0x00007fd04dd9fc90 in QGraphicsScenePrivate::filterDescendantEvent(QGraphicsItem*, QEvent*) () from /lib64/libQtGui.so.4
#60 0x00007fd04dda460e in QGraphicsScenePrivate::sendEvent(QGraphicsItem*, QEvent*) () from /lib64/libQtGui.so.4
#61 0x00007fd04dda4b47 in QGraphicsScenePrivate::sendMouseEvent(QGraphicsSceneMouseEvent*) () from /lib64/libQtGui.so.4
#62 0x00007fd04ddaeed6 in QGraphicsScene::mouseMoveEvent(QGraphicsSceneMouseEvent*) () from /lib64/libQtGui.so.4
#63 0x00007fd04ddbbaaf in QGraphicsScene::event(QEvent*) () from /lib64/libQtGui.so.4
#64 0x00007fd04d79af6c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /lib64/libQtGui.so.4
#65 0x00007fd04d7a19b8 in QApplication::notify(QObject*, QEvent*) () from /lib64/libQtGui.so.4
#66 0x00007fd04f6c69ea in KApplication::notify(QObject*, QEvent*) () from /lib64/libkdeui.so.5
#67 0x00007fd04e66143d in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /lib64/libQtCore.so.4
#68 0x00007fd04ddd1cd8 in QGraphicsViewPrivate::mouseMoveEventHandler(QMouseEvent*) () from /lib64/libQtGui.so.4
#69 0x00007fd04ddd2d6a in QGraphicsView::mouseMoveEvent(QMouseEvent*) () from /lib64/libQtGui.so.4
#70 0x00007fd04d7edfe8 in QWidget::event(QEvent*) () from /lib64/libQtGui.so.4
#71 0x00007fd04dbad29e in QFrame::event(QEvent*) () from /lib64/libQtGui.so.4
#72 0x00007fd04ddd4521 in QGraphicsView::viewportEvent(QEvent*) () from /lib64/libQtGui.so.4
#73 0x00007fd04e6615a6 in QCoreApplicationPrivate::sendThroughObjectEventFilters(QObject*, QEvent*) () from /lib64/libQtCore.so.4
#74 0x00007fd04d79af4c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /lib64/libQtGui.so.4
#75 0x00007fd04d7a1b1f in QApplication::notify(QObject*, QEvent*) () from /lib64/libQtGui.so.4
#76 0x00007fd04f6c69ea in KApplication::notify(QObject*, QEvent*) () from /lib64/libkdeui.so.5
#77 0x00007fd04e66143d in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /lib64/libQtCore.so.4
#78 0x00007fd04d7a114f in QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool) () from /lib64/libQtGui.so.4
#79 0x00007fd04d8174ee in QETWidget::translateMouseEvent(_XEvent const*) () from /lib64/libQtGui.so.4
#80 0x00007fd04d815ea2 in QApplication::x11ProcessEvent(_XEvent*) () from /lib64/libQtGui.so.4
#81 0x00007fd04d83e1b2 in x11EventSourceDispatch(_GSource*, int (*)(void*), void*) () from /lib64/libQtGui.so.4
#82 0x00007fd048f70aeb in g_main_context_dispatch () from /lib64/libglib-2.0.so.0
#83 0x00007fd048f70e88 in g_main_context_iterate.isra () from /lib64/libglib-2.0.so.0
#84 0x00007fd048f70f3c in g_main_context_iteration () from /lib64/libglib-2.0.so.0
#85 0x00007fd04e69069e in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib64/libQtCore.so.4
#86 0x00007fd04d83e346 in QGuiEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib64/libQtGui.so.4
#87 0x00007fd04e65ff91 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib64/libQtCore.so.4
#88 0x00007fd04e6602f5 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /lib64/libQtCore.so.4
#89 0x00007fd04e6659c7 in QCoreApplication::exec() () from /lib64/libQtCore.so.4
#90 0x00007fd02dddf5fd in kdemain () from /lib64/libkdeinit4_plasma-desktop.so
#91 0x000000000040825d in launch(int, char const*, char const*, char const*, int, char const*, bool, char const*, bool, char const*) ()
#92 0x00000000004090a9 in handle_launcher_request(int, char const*) [clone .isra.15] ()
#93 0x0000000000409787 in handle_requests(int) ()
#94 0x000000000040537d in main ()

Reported using DrKonqi