[Comment from a bug triager]
The backtrace is related to the crash in bug 264659 (~StackedUrlBar deletion)
Regards

I cannot ensure as I cannot reproduce properly but the cause for this should be fixed in 0.6.89.

I can reproduce this (or a similar crash) with current git:
1. open some web pages
2. go to private mode, open at least one web page
3. go back -> crash.

Backtrace:

Application: rekonq (kdeinit4), signal: Segmentation fault
[Current thread is 1 (Thread 0x7febbadf3760 (LWP 1874))]

Thread 13 (Thread 0x7feba091a700 (LWP 1891)):
#0  0x00007febb963534c in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007febafa1314c in WTF::TCMalloc_PageHeap::scavengerThread() () from /usr/lib/libQtWebKit.so.4
#2  0x00007febafa13189 in WTF::TCMalloc_PageHeap::runScavengerThread(void*) () from /usr/lib/libQtWebKit.so.4
#3  0x00007febacacfae3 in ?? () from /usr/lib/libGL.so.1
#4  0x00007febb9630cb0 in start_thread () from /lib/libpthread.so.0
#5  0x00007febb831495d in clone () from /lib/libc.so.6
#6  0x0000000000000000 in ?? ()

Thread 12 (Thread 0x7feb9f0f1700 (LWP 1892)):
#0  0x00007febb963534c in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007febae80768c in QTWTF::TCMalloc_PageHeap::scavengerThread (this=0x7febaeb2dda0) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:2359
#2  0x00007febae8076c9 in QTWTF::TCMalloc_PageHeap::runScavengerThread (context=0x7febaeb3be74) at ../3rdparty/javascriptcore/JavaScriptCore/wtf/FastMalloc.cpp:1464
#3  0x00007febacacfae3 in ?? () from /usr/lib/libGL.so.1
#4  0x00007febb9630cb0 in start_thread () from /lib/libpthread.so.0
#5  0x00007febb831495d in clone () from /lib/libc.so.6
#6  0x0000000000000000 in ?? ()

Thread 11 (Thread 0x7feb9d96a700 (LWP 1893)):
#0  0x00007febb963534c in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007febb98bf5d3 in wait (this=<value optimized out>, mutex=0x19ae1e0, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:88
#2  QWaitCondition::wait (this=<value optimized out>, mutex=0x19ae1e0, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:160
#3  0x00007febada64216 in ThreadWeaver::WeaverImpl::blockThreadUntilJobsAreBeingAssigned (this=0x19aded0, th=0x1c7d6c0) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/threadweaver/Weaver/WeaverImpl.cpp:365
#4  0x00007febada67ec0 in ThreadWeaver::WorkingHardState::applyForWork (this=0x19ae2c0, th=0x1c7d6c0) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/threadweaver/Weaver/WorkingHardState.cpp:71
#5  0x00007febada663e4 in ThreadWeaver::ThreadRunHelper::run (this=0x7feb9d969d70, parent=0x19aded0, th=0x1c7d6c0) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/threadweaver/Weaver/Thread.cpp:87
#6  0x00007febada664d4 in ThreadWeaver::Thread::run (this=0x1c7d6c0) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/threadweaver/Weaver/Thread.cpp:142
#7  0x00007febb98bedea in QThreadPrivate::start (arg=0x1c7d6c0) at thread/qthread_unix.cpp:320
#8  0x00007febacacfae3 in ?? () from /usr/lib/libGL.so.1
#9  0x00007febb9630cb0 in start_thread () from /lib/libpthread.so.0
#10 0x00007febb831495d in clone () from /lib/libc.so.6
#11 0x0000000000000000 in ?? ()

Thread 10 (Thread 0x7feb89922700 (LWP 2425)):
#0  0x00007febb963534c in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007febb98bf5d3 in wait (this=<value optimized out>, mutex=0x19ae1e0, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:88
#2  QWaitCondition::wait (this=<value optimized out>, mutex=0x19ae1e0, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:160
#3  0x00007febada64216 in ThreadWeaver::WeaverImpl::blockThreadUntilJobsAreBeingAssigned (this=0x19aded0, th=0x3038b70) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/threadweaver/Weaver/WeaverImpl.cpp:365
#4  0x00007febada67ec0 in ThreadWeaver::WorkingHardState::applyForWork (this=0x19ae2c0, th=0x3038b70) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/threadweaver/Weaver/WorkingHardState.cpp:71
#5  0x00007febada663e4 in ThreadWeaver::ThreadRunHelper::run (this=0x7feb89921d70, parent=0x19aded0, th=0x3038b70) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/threadweaver/Weaver/Thread.cpp:87
#6  0x00007febada664d4 in ThreadWeaver::Thread::run (this=0x3038b70) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/threadweaver/Weaver/Thread.cpp:142
#7  0x00007febb98bedea in QThreadPrivate::start (arg=0x3038b70) at thread/qthread_unix.cpp:320
#8  0x00007febacacfae3 in ?? () from /usr/lib/libGL.so.1
#9  0x00007febb9630cb0 in start_thread () from /lib/libpthread.so.0
#10 0x00007febb831495d in clone () from /lib/libc.so.6
#11 0x0000000000000000 in ?? ()

Thread 9 (Thread 0x7feb87181700 (LWP 2573)):
#0  0x00007febb963534c in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007febb98bf5d3 in wait (this=<value optimized out>, mutex=0x19ae1e0, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:88
#2  QWaitCondition::wait (this=<value optimized out>, mutex=0x19ae1e0, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:160
#3  0x00007febada64216 in ThreadWeaver::WeaverImpl::blockThreadUntilJobsAreBeingAssigned (this=0x19aded0, th=0x3bf5800) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/threadweaver/Weaver/WeaverImpl.cpp:365
#4  0x00007febada67ec0 in ThreadWeaver::WorkingHardState::applyForWork (this=0x19ae2c0, th=0x3bf5800) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/threadweaver/Weaver/WorkingHardState.cpp:71
#5  0x00007febada663e4 in ThreadWeaver::ThreadRunHelper::run (this=0x7feb87180d70, parent=0x19aded0, th=0x3bf5800) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/threadweaver/Weaver/Thread.cpp:87
#6  0x00007febada664d4 in ThreadWeaver::Thread::run (this=0x3bf5800) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/threadweaver/Weaver/Thread.cpp:142
#7  0x00007febb98bedea in QThreadPrivate::start (arg=0x3bf5800) at thread/qthread_unix.cpp:320
#8  0x00007febacacfae3 in ?? () from /usr/lib/libGL.so.1
#9  0x00007febb9630cb0 in start_thread () from /lib/libpthread.so.0
#10 0x00007febb831495d in clone () from /lib/libc.so.6
#11 0x0000000000000000 in ?? ()

Thread 8 (Thread 0x7feb86980700 (LWP 2601)):
#0  0x00007febb963534c in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007febb98bf5d3 in wait (this=<value optimized out>, mutex=0x19ae1e0, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:88
#2  QWaitCondition::wait (this=<value optimized out>, mutex=0x19ae1e0, time=18446744073709551615) at thread/qwaitcondition_unix.cpp:160
#3  0x00007febada64216 in ThreadWeaver::WeaverImpl::blockThreadUntilJobsAreBeingAssigned (this=0x19aded0, th=0x3ac1e10) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/threadweaver/Weaver/WeaverImpl.cpp:365
#4  0x00007febada67ec0 in ThreadWeaver::WorkingHardState::applyForWork (this=0x19ae2c0, th=0x3ac1e10) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/threadweaver/Weaver/WorkingHardState.cpp:71
#5  0x00007febada663e4 in ThreadWeaver::ThreadRunHelper::run (this=0x7feb8697fd70, parent=0x19aded0, th=0x3ac1e10) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/threadweaver/Weaver/Thread.cpp:87
#6  0x00007febada664d4 in ThreadWeaver::Thread::run (this=0x3ac1e10) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/threadweaver/Weaver/Thread.cpp:142
#7  0x00007febb98bedea in QThreadPrivate::start (arg=0x3ac1e10) at thread/qthread_unix.cpp:320
#8  0x00007febacacfae3 in ?? () from /usr/lib/libGL.so.1
#9  0x00007febb9630cb0 in start_thread () from /lib/libpthread.so.0
#10 0x00007febb831495d in clone () from /lib/libc.so.6
#11 0x0000000000000000 in ?? ()

Thread 7 (Thread 0x7feb87a2f700 (LWP 7155)):
#0  0x00007febb96356cb in pthread_cond_timedwait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007febb98bf4fd in wait (this=<value optimized out>, mutex=0x302c640, time=30000) at thread/qwaitcondition_unix.cpp:86
#2  QWaitCondition::wait (this=<value optimized out>, mutex=0x302c640, time=30000) at thread/qwaitcondition_unix.cpp:160
#3  0x00007febb98b2477 in QThreadPoolThread::run (this=0x1994e10) at concurrent/qthreadpool.cpp:140
#4  0x00007febb98bedea in QThreadPrivate::start (arg=0x1994e10) at thread/qthread_unix.cpp:320
#5  0x00007febacacfae3 in ?? () from /usr/lib/libGL.so.1
#6  0x00007febb9630cb0 in start_thread () from /lib/libpthread.so.0
#7  0x00007febb831495d in clone () from /lib/libc.so.6
#8  0x0000000000000000 in ?? ()

Thread 6 (Thread 0x7feb836e9700 (LWP 7156)):
#0  0x00007febb96356cb in pthread_cond_timedwait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007febb98bf4fd in wait (this=<value optimized out>, mutex=0x3032780, time=30000) at thread/qwaitcondition_unix.cpp:86
#2  QWaitCondition::wait (this=<value optimized out>, mutex=0x3032780, time=30000) at thread/qwaitcondition_unix.cpp:160
#3  0x00007febb98b2477 in QThreadPoolThread::run (this=0x3637c60) at concurrent/qthreadpool.cpp:140
#4  0x00007febb98bedea in QThreadPrivate::start (arg=0x3637c60) at thread/qthread_unix.cpp:320
#5  0x00007febacacfae3 in ?? () from /usr/lib/libGL.so.1
#6  0x00007febb9630cb0 in start_thread () from /lib/libpthread.so.0
#7  0x00007febb831495d in clone () from /lib/libc.so.6
#8  0x0000000000000000 in ?? ()

Thread 5 (Thread 0x7feb7bfff700 (LWP 7157)):
#0  0x00007febb96356cb in pthread_cond_timedwait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007febb98bf4fd in wait (this=<value optimized out>, mutex=0x3032780, time=30000) at thread/qwaitcondition_unix.cpp:86
#2  QWaitCondition::wait (this=<value optimized out>, mutex=0x3032780, time=30000) at thread/qwaitcondition_unix.cpp:160
#3  0x00007febb98b2477 in QThreadPoolThread::run (this=0x1c174e0) at concurrent/qthreadpool.cpp:140
#4  0x00007febb98bedea in QThreadPrivate::start (arg=0x1c174e0) at thread/qthread_unix.cpp:320
#5  0x00007febacacfae3 in ?? () from /usr/lib/libGL.so.1
#6  0x00007febb9630cb0 in start_thread () from /lib/libpthread.so.0
#7  0x00007febb831495d in clone () from /lib/libc.so.6
#8  0x0000000000000000 in ?? ()

Thread 4 (Thread 0x7feb84cd5700 (LWP 7158)):
#0  0x00007febb96356cb in pthread_cond_timedwait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007febb98bf4fd in wait (this=<value optimized out>, mutex=0x3032780, time=30000) at thread/qwaitcondition_unix.cpp:86
#2  QWaitCondition::wait (this=<value optimized out>, mutex=0x3032780, time=30000) at thread/qwaitcondition_unix.cpp:160
#3  0x00007febb98b2477 in QThreadPoolThread::run (this=0x3695f20) at concurrent/qthreadpool.cpp:140
#4  0x00007febb98bedea in QThreadPrivate::start (arg=0x3695f20) at thread/qthread_unix.cpp:320
#5  0x00007febacacfae3 in ?? () from /usr/lib/libGL.so.1
#6  0x00007febb9630cb0 in start_thread () from /lib/libpthread.so.0
#7  0x00007febb831495d in clone () from /lib/libc.so.6
#8  0x0000000000000000 in ?? ()

Thread 3 (Thread 0x7feb82014700 (LWP 7159)):
#0  0x00007febb96356cb in pthread_cond_timedwait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007febb98bf4fd in wait (this=<value optimized out>, mutex=0x3032780, time=30000) at thread/qwaitcondition_unix.cpp:86
#2  QWaitCondition::wait (this=<value optimized out>, mutex=0x3032780, time=30000) at thread/qwaitcondition_unix.cpp:160
#3  0x00007febb98b2477 in QThreadPoolThread::run (this=0x32df570) at concurrent/qthreadpool.cpp:140
#4  0x00007febb98bedea in QThreadPrivate::start (arg=0x32df570) at thread/qthread_unix.cpp:320
#5  0x00007febacacfae3 in ?? () from /usr/lib/libGL.so.1
#6  0x00007febb9630cb0 in start_thread () from /lib/libpthread.so.0
#7  0x00007febb831495d in clone () from /lib/libc.so.6
#8  0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7feb7b7fe700 (LWP 7161)):
#0  0x00007febb96356cb in pthread_cond_timedwait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#1  0x00007febb98bf4fd in wait (this=<value optimized out>, mutex=0x3032780, time=30000) at thread/qwaitcondition_unix.cpp:86
#2  QWaitCondition::wait (this=<value optimized out>, mutex=0x3032780, time=30000) at thread/qwaitcondition_unix.cpp:160
#3  0x00007febb98b2477 in QThreadPoolThread::run (this=0x30396b0) at concurrent/qthreadpool.cpp:140
#4  0x00007febb98bedea in QThreadPrivate::start (arg=0x30396b0) at thread/qthread_unix.cpp:320
#5  0x00007febacacfae3 in ?? () from /usr/lib/libGL.so.1
#6  0x00007febb9630cb0 in start_thread () from /lib/libpthread.so.0
#7  0x00007febb831495d in clone () from /lib/libc.so.6
#8  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7febbadf3760 (LWP 1874)):
[KCrash Handler]
#6  0x00007febb8dcce3a in QStyleSheetStyle::event (this=0x1bd16d0, e=0x7fffccc315f0) at styles/qstylesheetstyle.cpp:5801
#7  0x00007febb8a68e40 in QApplicationPrivate::notify_helper (this=0x18aa230, receiver=0x1bd16d0, e=0x7fffccc315f0) at kernel/qapplication.cpp:4462
#8  0x00007febb8a6e0e1 in QApplication::notify (this=<value optimized out>, receiver=0x1bd16d0, e=0x7fffccc315f0) at kernel/qapplication.cpp:4341
#9  0x00007febba771f51 in KApplication::notify (this=0x7fffccc32790, receiver=0x1bd16d0, event=0x7fffccc315f0) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/kdeui/kernel/kapplication.cpp:311
#10 0x00007febb99b5eab in QCoreApplication::notifyInternal (this=0x7fffccc32790, receiver=0x1bd16d0, event=0x7fffccc315f0) at kernel/qcoreapplication.cpp:731
#11 0x00007febb8a678d2 in sendEvent (focus=0x0, reason=Qt::OtherFocusReason) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#12 QApplicationPrivate::setFocusWidget (focus=0x0, reason=Qt::OtherFocusReason) at kernel/qapplication.cpp:2235
#13 0x00007febb8ab1404 in QWidget::clearFocus (this=0x438f610) at kernel/qwidget.cpp:6434
#14 0x00007febb8abd541 in QWidget::~QWidget (this=0x438f610, __in_chrg=<value optimized out>) at kernel/qwidget.cpp:1563
#15 0x00007feba7b9a61d in UrlBar::~UrlBar (this=0x438f610, __in_chrg=<value optimized out>) at /home/felix/Development/rekonq/src/urlbar/urlbar.cpp:123
#16 0x00007feba7b9a662 in UrlBar::~UrlBar (this=0x438f610, __in_chrg=<value optimized out>) at /home/felix/Development/rekonq/src/urlbar/urlbar.cpp:127
#17 0x00007febb99cb250 in QObjectPrivate::deleteChildren (this=0x4b7a6f0) at kernel/qobject.cpp:1955
#18 0x00007febb8abd607 in QWidget::~QWidget (this=0x440aca0, __in_chrg=<value optimized out>) at kernel/qwidget.cpp:1631
#19 0x00007feba7b99c76 in StackedUrlBar::~StackedUrlBar (this=0x440aca0, __in_chrg=<value optimized out>) at /home/felix/Development/rekonq/src/urlbar/stackedurlbar.h:42
#20 0x00007feba7b99cb2 in StackedUrlBar::~StackedUrlBar (this=0x440aca0, __in_chrg=<value optimized out>) at /home/felix/Development/rekonq/src/urlbar/stackedurlbar.h:42
#21 0x00007febb8ac9b6a in QWidgetAction::~QWidgetAction (this=0x4f3f830, __in_chrg=<value optimized out>) at kernel/qwidgetaction.cpp:128
#22 0x00007febba698069 in KAction::~KAction (this=0x4f3f830, __in_chrg=<value optimized out>) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/kdeui/actions/kaction.cpp:171
#23 0x00007febb99cb250 in QObjectPrivate::deleteChildren (this=0x38183e0) at kernel/qobject.cpp:1955
#24 0x00007febb8abd607 in QWidget::~QWidget (this=0x3e81ed0, __in_chrg=<value optimized out>) at kernel/qwidget.cpp:1631
#25 0x00007febba832e9a in KMainWindow::~KMainWindow (this=0x3e81ed0, __in_chrg=<value optimized out>) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/kdeui/widgets/kmainwindow.cpp:467
#26 0x00007feba7b36529 in MainWindow::~MainWindow (this=0x3e81ed0, __in_chrg=<value optimized out>, __vtt_parm=<value optimized out>) at /home/felix/Development/rekonq/src/mainwindow.cpp:166
#27 0x00007feba7b3659c in MainWindow::~MainWindow (this=0x3e81ed0, __in_chrg=<value optimized out>, __vtt_parm=<value optimized out>) at /home/felix/Development/rekonq/src/mainwindow.cpp:171
#28 0x00007febb99cc458 in QObject::event (this=0x3e81ed0, e=<value optimized out>) at kernel/qobject.cpp:1200
#29 0x00007febb8ac213c in QWidget::event (this=0x3e81ed0, event=0x415a5a0) at kernel/qwidget.cpp:8718
#30 0x00007febb8eda2b3 in QMainWindow::event (this=0x3e81ed0, event=0x415a5a0) at widgets/qmainwindow.cpp:1480
#31 0x00007feba7b3da21 in MainWindow::event (this=0x3e81ed0, event=0x415a5a0) at /home/felix/Development/rekonq/src/mainwindow.cpp:1106
#32 0x00007febb8a68e40 in QApplicationPrivate::notify_helper (this=0x18aa230, receiver=0x3e81ed0, e=0x415a5a0) at kernel/qapplication.cpp:4462
#33 0x00007febb8a6e0e1 in QApplication::notify (this=<value optimized out>, receiver=0x3e81ed0, e=0x415a5a0) at kernel/qapplication.cpp:4341
#34 0x00007febba771f51 in KApplication::notify (this=0x7fffccc32790, receiver=0x3e81ed0, event=0x415a5a0) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/kdeui/kernel/kapplication.cpp:311
#35 0x00007febb99b5eab in QCoreApplication::notifyInternal (this=0x7fffccc32790, receiver=0x3e81ed0, event=0x415a5a0) at kernel/qcoreapplication.cpp:731
#36 0x00007febb99b9e41 in sendEvent (receiver=0x0, event_type=0, data=0x175fb00) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#37 QCoreApplicationPrivate::sendPostedEvents (receiver=0x0, event_type=0, data=0x175fb00) at kernel/qcoreapplication.cpp:1372
#38 0x00007febb99e3e73 in sendPostedEvents (s=0x18adac0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:220
#39 postEventSourceDispatch (s=0x18adac0) at kernel/qeventdispatcher_glib.cpp:277
#40 0x00007febb533cbf3 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#41 0x00007febb533d3d0 in ?? () from /usr/lib/libglib-2.0.so.0
#42 0x00007febb533d66d in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#43 0x00007febb99e3fda in QEventDispatcherGlib::processEvents (this=0x1761cf0, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:422
#44 0x00007febb8b1aa06 in QGuiEventDispatcherGlib::processEvents (this=<value optimized out>, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:204
#45 0x00007febb99b4912 in QEventLoop::processEvents (this=<value optimized out>, flags=...) at kernel/qeventloop.cpp:149
#46 0x00007febb99b4b94 in QEventLoop::exec (this=0x7fffccc32700, flags=...) at kernel/qeventloop.cpp:201
#47 0x00007febb99ba11b in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1008
#48 0x00007feba7bc5113 in kdemain (argc=2, argv=0x1867d00) at /home/felix/Development/rekonq/src/main.cpp:215
#49 0x00000000004078ec in launch (argc=<value optimized out>, _name=0x18a9518 "rekonq", args=<value optimized out>, cwd=0x18a951f "http://www.schwaebische-post.de/544693", envc=-859623104, envs=<value optimized out>, reset_env=false, tty=0x0, avoid_loops=false, startup_id_str=0x40b781 "0") at /var/abs/local/kdelibs/src/kdelibs-4.6.1/kinit/kinit.cpp:734
#50 0x00000000004084fb in handle_launcher_request (sock=<value optimized out>, who=<value optimized out>) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/kinit/kinit.cpp:1226
#51 0x00000000004089f2 in handle_requests (waitForPid=<value optimized out>) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/kinit/kinit.cpp:1419
#52 0x0000000000408e77 in main (argc=4, argv=0x7fffccc33ad8, envp=0x7fffccc33b00) at /var/abs/local/kdelibs/src/kdelibs-4.6.1/kinit/kinit.cpp:1907

Git commit 8eef7ab62aefcebfa0242ed1f7a402df84ba995e by Andrea Diamantini.
Committed on 23/03/2011 at 21:52.
Pushed by adjam into branch 'master'.

Stop timers before deleting objects.

CCBUG:268328
CCBUG:266937

M  +2    -0    src/mainwindow.cpp     
M  +1    -0    src/urlbar/urlbar.cpp     

http://commits.kde.org/rekonq/8eef7ab62aefcebfa0242ed1f7a402df84ba995e

I'm still getting crashes.

Hmm, now it works... Maybe I had still an old version running. Anyway, now it looks like the bug is fixed.

*** Bug 272573 has been marked as a duplicate of this bug. ***

*** Bug 273027 has been marked as a duplicate of this bug. ***

*** Bug 276880 has been marked as a duplicate of this bug. ***

*** Bug 279648 has been marked as a duplicate of this bug. ***

*** Bug 280938 has been marked as a duplicate of this bug. ***

Git commit 8302ea16430afc414807c5251f04f129172e8995 by Andrea Diamantini.
Committed on 13/10/2011 at 00:58.
Pushed by adjam into branch 'master'.

Fix crash on private mode store/restore

This commit, while does not perfectly fix the issue, "workaround" it
a lot to fix crashes on private mode enter/exit

- improve session store/restore
- improve session manager code
- calm down kDebug messages
- applies code style

CCBUG: 268328

M  +19   -8    src/application.cpp
M  +4    -1    src/mainview.h
M  +67   -17   src/sessionmanager.cpp
M  +13   -2    src/sessionmanager.h
M  +0    -1    src/urlbar/listitem.cpp

http://commits.kde.org/rekonq/8302ea16430afc414807c5251f04f129172e8995

Created attachment 64863 [details]
New crash information added by DrKonqi

rekonq (0.8.0) on KDE Platform 4.7.2 (4.7.2) using Qt 4.7.4

- What I was doing when the application crashed:
I deactivated private mode. The animation of the normal mode window showed up but then rekonq crashed.
- Custom settings of the application:
3 tabs were open. nothing special on it as far as I remember.

-- Backtrace (Reduced):
#6  0x00007fc858539692 in QStyleSheetStyle::event (this=0xf7d9250, e=0x7fffb37a08b0) at styles/qstylesheetstyle.cpp:5808
#7  0x00007fc858222424 in notify_helper (e=0x7fffb37a08b0, receiver=0xf7d9250, this=0x6d02c0) at kernel/qapplication.cpp:4486
#8  QApplicationPrivate::notify_helper (this=0x6d02c0, receiver=0xf7d9250, e=0x7fffb37a08b0) at kernel/qapplication.cpp:4458
#9  0x00007fc858227291 in QApplication::notify (this=0x7fffb37a1640, receiver=0xf7d9250, e=0x7fffb37a08b0) at kernel/qapplication.cpp:4365
#10 0x00007fc85a759126 in KApplication::notify (this=0x7fffb37a1640, receiver=0xf7d9250, event=0x7fffb37a08b0) at ../../kdeui/kernel/kapplication.cpp:311

*** Bug 281923 has been marked as a duplicate of this bug. ***

*** Bug 283363 has been marked as a duplicate of this bug. ***

*** Bug 284995 has been marked as a duplicate of this bug. ***

*** Bug 285386 has been marked as a duplicate of this bug. ***

Created attachment 65239 [details]
New crash information added by DrKonqi

rekonq (0.8.0) on KDE Platform 4.7.2 (4.7.2) using Qt 4.7.4

- What I was doing when the application crashed:

Closing Private Mode (after browsing Facebook in Private Mode)

-- Backtrace (Reduced):
#6  0x00007f6233fb7692 in QStyleSheetStyle::event (this=0x6521b80, e=0x7fff2364c8b0) at styles/qstylesheetstyle.cpp:5808
#7  0x00007f6233ca0424 in notify_helper (e=0x7fff2364c8b0, receiver=0x6521b80, this=0x21f2490) at kernel/qapplication.cpp:4486
#8  QApplicationPrivate::notify_helper (this=0x21f2490, receiver=0x6521b80, e=0x7fff2364c8b0) at kernel/qapplication.cpp:4458
#9  0x00007f6233ca5291 in QApplication::notify (this=0x7fff2364d640, receiver=0x6521b80, e=0x7fff2364c8b0) at kernel/qapplication.cpp:4365
#10 0x00007f62361d7126 in KApplication::notify (this=0x7fff2364d640, receiver=0x6521b80, event=0x7fff2364c8b0) at ../../kdeui/kernel/kapplication.cpp:311

Created attachment 65278 [details]
New crash information added by DrKonqi

rekonq (0.8.0) on KDE Platform 4.7.2 (4.7.2) using Qt 4.7.4

- What I was doing when the application crashed:

I was leaving private mode and wanted to go back to normal mode.

-- Backtrace (Reduced):
#6  0x00007f0263feb692 in QStyleSheetStyle::event (this=0x29aadd0, e=0x7fffa8f70650) at styles/qstylesheetstyle.cpp:5808
#7  0x00007f0263cd4424 in notify_helper (e=0x7fffa8f70650, receiver=0x29aadd0, this=0x23c9f10) at kernel/qapplication.cpp:4486
#8  QApplicationPrivate::notify_helper (this=0x23c9f10, receiver=0x29aadd0, e=0x7fffa8f70650) at kernel/qapplication.cpp:4458
#9  0x00007f0263cd9291 in QApplication::notify (this=0x7fffa8f713e0, receiver=0x29aadd0, e=0x7fffa8f70650) at kernel/qapplication.cpp:4365
#10 0x00007f026620b126 in KApplication::notify (this=0x7fffa8f713e0, receiver=0x29aadd0, event=0x7fffa8f70650) at ../../kdeui/kernel/kapplication.cpp:311

*** Bug 286064 has been marked as a duplicate of this bug. ***

*** Bug 286330 has been marked as a duplicate of this bug. ***

*** Bug 286183 has been marked as a duplicate of this bug. ***

Created attachment 66407 [details]
New crash information added by DrKonqi

rekonq (0.8.0) on KDE Platform 4.7.3 (4.7.3) using Qt 4.7.4

I was returning from private mode browsing.

-- Backtrace (Reduced):
#6  0x00007f0a411a5692 in QStyleSheetStyle::event (this=0x2616570, e=0x7fff342f57d0) at styles/qstylesheetstyle.cpp:5808
#7  0x00007f0a40e8e424 in notify_helper (e=0x7fff342f57d0, receiver=0x2616570, this=0x1f11190) at kernel/qapplication.cpp:4486
#8  QApplicationPrivate::notify_helper (this=0x1f11190, receiver=0x2616570, e=0x7fff342f57d0) at kernel/qapplication.cpp:4458
#9  0x00007f0a40e93291 in QApplication::notify (this=0x7fff342f6560, receiver=0x2616570, e=0x7fff342f57d0) at kernel/qapplication.cpp:4365
#10 0x00007f0a433c6126 in KApplication::notify (this=0x7fff342f6560, receiver=0x2616570, event=0x7fff342f57d0) at ../../kdeui/kernel/kapplication.cpp:311

Created attachment 66637 [details]
New crash information added by DrKonqi

rekonq (0.8.1) on KDE Platform 4.7.3 (4.7.3) using Qt 4.7.4

Try switching between private browsing mode and normal mode a few times. Yes I was deliberately trying to crash the browser.

-- Backtrace (Reduced):
#6  0x00007f61335bf692 in QStyleSheetStyle::event (this=0x26f8770, e=0x7fff4b67e810) at styles/qstylesheetstyle.cpp:5808
#7  0x00007f61332a8424 in notify_helper (e=0x7fff4b67e810, receiver=0x26f8770, this=0x2009a50) at kernel/qapplication.cpp:4486
#8  QApplicationPrivate::notify_helper (this=0x2009a50, receiver=0x26f8770, e=0x7fff4b67e810) at kernel/qapplication.cpp:4458
#9  0x00007f61332ad291 in QApplication::notify (this=0x7fff4b67f5a0, receiver=0x26f8770, e=0x7fff4b67e810) at kernel/qapplication.cpp:4365
#10 0x00007f61357e0126 in KApplication::notify (this=0x7fff4b67f5a0, receiver=0x26f8770, event=0x7fff4b67e810) at ../../kdeui/kernel/kapplication.cpp:311

*** Bug 289209 has been marked as a duplicate of this bug. ***

It finally works here, cause of qtwebkit upgrade and a couple of fixes "probably" related.
Please, confirm it with:
rekonq master
KDE 4.7.x
qtwebkit 2.2.x.

I could browse and switch 12 times from private mode to normal one.

Tried without debugger installed, failed returning from "private" to normal where there were two tabs open & active. Crashed immediately after clearing the "Private browsing" menu selection. This happens without navigating to anywhere during "Private browsing."

KDE 4.7.2
Rekonq 0.8.0
qtwebkit-source (2.2~2011week36-0ubuntu1) oneiric
kde4libs (4:4.7.3-0ubuntu0.1) oneiric-proposed

Yes, Robert. I'm aware rekonq 0.8 is affected. I was asking if someone testing/using rekonq compiled from master branch (the one that will become 0.9) is.

Created attachment 67241 [details]
New crash information added by DrKonqi

rekonq (0.8.57) on KDE Platform 4.7.95 (4.8 RC1 (4.7.95) using Qt 4.7.4

- What I was doing when the application crashed:
 I was testing the latest build I made after getting source via "git clone git://anongit.kde.org/rekonq "

-- Backtrace (Reduced):
#6  0x00007f2d6e786692 in QStyleSheetStyle::event (this=0x28e6050, e=0x7fffbc14ab60) at styles/qstylesheetstyle.cpp:5808
#7  0x00007f2d6e46f424 in notify_helper (e=0x7fffbc14ab60, receiver=0x28e6050, this=0x24d2b30) at kernel/qapplication.cpp:4486
#8  QApplicationPrivate::notify_helper (this=0x24d2b30, receiver=0x28e6050, e=0x7fffbc14ab60) at kernel/qapplication.cpp:4458
#9  0x00007f2d6e474291 in QApplication::notify (this=0x7fffbc14b8f0, receiver=0x28e6050, e=0x7fffbc14ab60) at kernel/qapplication.cpp:4365
#10 0x00007f2d709aaa46 in KApplication::notify (this=0x7fffbc14b8f0, receiver=0x28e6050, event=0x7fffbc14ab60) at ../../kdeui/kernel/kapplication.cpp:311

(In reply to comment #29)
> Created an attachment (id=67241) [details]
> New crash information added by DrKonqi
> 
> rekonq (0.8.57) on KDE Platform 4.7.95 (4.8 RC1 (4.7.95) using Qt 4.7.4

Can you please test again with Qt 4.8 and using qtwebkit2.2 (available by default there)?

Umm, KDE RC1 comes from a ppa the Kubuntu team set up for testing with Oneiric. So, unless they put a Qt update in there or anywhere else, I'm unable to help further :/

(In reply to comment #31)
> Umm, KDE RC1 comes from a ppa the Kubuntu team set up for testing with Oneiric.
> So, unless they put a Qt update in there or anywhere else, I'm unable to help
> further :/

Ok Silviu, no worries! And many thanks for help :D

It seems this is a specific qt bug, fixed in qt 4.8: https://bugreports.qt.nokia.com/browse/QTBUG-19872.

Can someone of you confirm?

*** Bug 287391 has been marked as a duplicate of this bug. ***

Created attachment 68025 [details]
New crash information added by DrKonqi

rekonq (0.8.0) on KDE Platform 4.7.3 (4.7.3) using Qt 4.7.4

- What I was doing when the application crashed:

started konqueror and quickly closed it's window. Using default Kubuntu (KDE desktop environment)

-- Backtrace (Reduced):
#6  0x00007f77b297e692 in QStyleSheetStyle::event (this=0x2312600, e=0x7ffffc5117d0) at styles/qstylesheetstyle.cpp:5808
#7  0x00007f77b2667424 in notify_helper (e=0x7ffffc5117d0, receiver=0x2312600, this=0x1bd98e0) at kernel/qapplication.cpp:4486
#8  QApplicationPrivate::notify_helper (this=0x1bd98e0, receiver=0x2312600, e=0x7ffffc5117d0) at kernel/qapplication.cpp:4458
#9  0x00007f77b266c291 in QApplication::notify (this=0x7ffffc512560, receiver=0x2312600, e=0x7ffffc5117d0) at kernel/qapplication.cpp:4365
#10 0x00007f77b4b9f126 in KApplication::notify (this=0x7ffffc512560, receiver=0x2312600, event=0x7ffffc5117d0) at ../../kdeui/kernel/kapplication.cpp:311

*** Bug 290044 has been marked as a duplicate of this bug. ***

*** Bug 292005 has been marked as a duplicate of this bug. ***

*** Bug 292915 has been marked as a duplicate of this bug. ***

*** Bug 293156 has been marked as a duplicate of this bug. ***

*** Bug 293312 has been marked as a duplicate of this bug. ***

*** Bug 293497 has been marked as a duplicate of this bug. ***

*** Bug 293812 has been marked as a duplicate of this bug. ***

Created attachment 69306 [details]
drkonqi generated backtrace

rekonq didnt crash after returning from private mode, but closing rekonq while in private mode

Created attachment 69307 [details]
drkonqi generated backtrace

rekonq crashed after exiting the (main) window while in private browsing mode

Comment on attachment 69307 [details]
drkonqi generated backtrace

rekonq crashed exiting while in private browsing mode

*** Bug 296612 has been marked as a duplicate of this bug. ***

*** Bug 273408 has been marked as a duplicate of this bug. ***

*** Bug 300694 has been marked as a duplicate of this bug. ***

Excuse me but how is this bug a duplicate of my bug Bug 300694 ? Rekonq shouldn't even open kdenlive files in the first place!!!! And i never used private browsing. Sure it may be that same libraries caused the crash. but the situation is completelly different. in my case there was no private browsing and rekonq was opening empty tabs automaticly for some time. until it crashed.

(In reply to comment #49)
> Excuse me but how is this bug a duplicate of my bug Bug 300694 ? Rekonq
> shouldn't even open kdenlive files in the first place!!!! And i never used
> private browsing. Sure it may be that same libraries caused the crash. but
> the situation is completelly different. in my case there was no private
> browsing and rekonq was opening empty tabs automaticly for some time. until
> it crashed.

Gregor, I understand you find this strange, but please think about it for a moment. Noone is saying here that the two situations described in the bugs are similar, we just noticed they lead to same situation in the same piece of code. Fix it and both will restart working as desired.

Regards

*** Bug 301198 has been marked as a duplicate of this bug. ***

*** Bug 301251 has been marked as a duplicate of this bug. ***

Created attachment 71854 [details]
New crash information added by DrKonqi

rekonq (0.9.1) on KDE Platform 4.8.3 (4.8.3) using Qt 4.8.1

- What I was doing when the application crashed:

Switching from private browsing mode to normal mode.

-- Backtrace (Reduced):
#8  0xb4611b76 in QStyleSheetStyle::event (this=0x8c812c0, e=0xbfefbe00) at styles/qstylesheetstyle.cpp:5798
#9  0xb4298ed4 in notify_helper (e=0xbfefbe00, receiver=0x8c812c0, this=0x89bbfb0) at kernel/qapplication.cpp:4559
#10 QApplicationPrivate::notify_helper (this=0x89bbfb0, receiver=0x8c812c0, e=0xbfefbe00) at kernel/qapplication.cpp:4531
#11 0xb429e30d in QApplication::notify (this=0xbfefbe00, receiver=0x8c812c0, e=0xbfefbe00) at kernel/qapplication.cpp:4288
#12 0xb5643b61 in KApplication::notify (this=0xbfefced8, receiver=0x8c812c0, event=0xbfefbe00) at ../../kdeui/kernel/kapplication.cpp:311

*** Bug 302658 has been marked as a duplicate of this bug. ***

Git commit ba9fa320c47eaf322abe11e1a6b6708620b65fdf by Andrea Diamantini.
Committed on 03/07/2012 at 19:11.
Pushed by adjam into branch 'master'.

Get sure UrlBar is deleted well (i.e. later) and in the right place
(i.e. the WebTab dtor).

I cannot no more reproduce the problems described in #296346, #300892
and #268328

What about you?
Related: bug 296346, bug 300892

M  +10   -0    src/mainview.cpp
M  +2    -1    src/mainview.h
M  +7    -2    src/webtab.cpp

http://commits.kde.org/rekonq/ba9fa320c47eaf322abe11e1a6b6708620b65fdf

*** Bug 301864 has been marked as a duplicate of this bug. ***

*** Bug 303973 has been marked as a duplicate of this bug. ***

Yes, commit ba9fa320c47 fixed it!

*** Bug 304185 has been marked as a duplicate of this bug. ***

*** Bug 304040 has been marked as a duplicate of this bug. ***

*** Bug 305080 has been marked as a duplicate of this bug. ***

Should the above mentioned fix be contained in 1.0? Because I get this crash with 1.0 when closing browser windows. I've never used private mode with this installation.

Created attachment 74006 [details]
New crash information added by DrKonqi

rekonq (1.1) on KDE Platform 4.9.1 using Qt 4.8.3

- What I was doing when the application crashed:

Closed multitabbed Rekonq window by mouse click.

-- Backtrace (Reduced):
#6  0x00007f4ed9fccfa2 in QStyleSheetStyle::event (this=0x21eb700, e=0x7fff79852970) at styles/qstylesheetstyle.cpp:5798
#7  0x00007f4ed9cb8dfc in QApplicationPrivate::notify_helper (this=this@entry=0x1938ec0, receiver=receiver@entry=0x21eb700, e=e@entry=0x7fff79852970) at kernel/qapplication.cpp:4557
#8  0x00007f4ed9cbab7a in QApplication::notify (this=0x7fff79853b40, receiver=0x21eb700, e=0x7fff79852970) at kernel/qapplication.cpp:4418
#9  0x00007f4edb8b56b6 in KApplication::notify (this=0x7fff79853b40, receiver=0x21eb700, event=0x7fff79852970) at /var/tmp/portage/kde-base/kdelibs-4.9.1/work/kdelibs-4.9.1/kdeui/kernel/kapplication.cpp:311
#10 0x00007f4edaafc15e in QCoreApplication::notifyInternal (this=0x7fff79853b40, receiver=0x21eb700, event=0x7fff79852970) at kernel/qcoreapplication.cpp:915

I still get the crash with this backtrace when I exit private mode and I has multiple tabs open. KDE Platform 4.9.2, Rekonq 1.1, Qt 4.8.3

*** Bug 310470 has been marked as a duplicate of this bug. ***