Sorry, but your backtrace is not useful, as you are lacking debugging symbols. If you can reproduce this bug, please check here on how to get a valid backtrace:

http://techbase.kde.org/Development/Tutorials/Debugging/How_to_create_useful_crash_reports

Created attachment 57088 [details]
New crash information added by DrKonqi

amarok (2.4.0) on KDE Platform 4.6.00 (4.6.0) using Qt 4.7.1

- What I was doing when the application crashed:

In the left upper breacrumb navigation go to Files and from the drop down list choose a directory. Amarok crashed.

-- Backtrace (Reduced):
#7  0x00007f2479a9a82e in operator= (this=0x2e237e0, action=0x3c76370, action_e=QAction::Trigger, self=true) at ../../src/corelib/kernel/qpointer.h:68
#8  QMenuPrivate::activateAction (this=0x2e237e0, action=0x3c76370, action_e=QAction::Trigger, self=true) at widgets/qmenu.cpp:1098
#9  0x00007f24796ad4a8 in QWidget::event (this=0x3eac420, event=0x7fffae44afe0) at kernel/qwidget.cpp:8200
#10 0x00007f2479a9b9fb in QMenu::event (this=0x3eac420, e=0x7fffae44afe0) at widgets/qmenu.cpp:2410
#11 0x00007f247965bcd4 in QApplicationPrivate::notify_helper (this=0x7ef310, receiver=0x3eac420, e=0x7fffae44afe0) at kernel/qapplication.cpp:4445

Created attachment 57089 [details]
New crash information added by DrKonqi

amarok (2.4.0) on KDE Platform 4.6.00 (4.6.0) using Qt 4.7.1

- What I was doing when the application crashed:

On my machine this bug is easily reproducible. If the backtrace is not useful, please tell me which debug libraries should I install.

-- Backtrace (Reduced):
#7  0x00007f9d72d7b82e in operator= (this=0x34938d0, action=0x1a37490, action_e=QAction::Trigger, self=true) at ../../src/corelib/kernel/qpointer.h:68
#8  QMenuPrivate::activateAction (this=0x34938d0, action=0x1a37490, action_e=QAction::Trigger, self=true) at widgets/qmenu.cpp:1098
#9  0x00007f9d7298e4a8 in QWidget::event (this=0x19099b0, event=0x7fffb1e74b60) at kernel/qwidget.cpp:8200
#10 0x00007f9d72d7c9fb in QMenu::event (this=0x19099b0, e=0x7fffb1e74b60) at widgets/qmenu.cpp:2410
#11 0x00007f9d7293ccd4 in QApplicationPrivate::notify_helper (this=0x7ebb70, receiver=0x19099b0, e=0x7fffb1e74b60) at kernel/qapplication.cpp:4445

Created attachment 57090 [details]
Click here twice or three times. Crashes the application instantly.

Backtrace from comment #2:

Thread 1 (Thread 0x7f247c1317a0 (LWP 18311)):
[KCrash Handler]
#6  QMetaObject::changeGuard (ptr=0x2e23aa8, o=0x0) at kernel/qobject.cpp:470
#7  0x00007f2479a9a82e in operator= (this=0x2e237e0, action=0x3c76370, action_e=QAction::Trigger, self=true) at ../../src/corelib/kernel/qpointer.h:68
#8  QMenuPrivate::activateAction (this=0x2e237e0, action=0x3c76370, action_e=QAction::Trigger, self=true) at widgets/qmenu.cpp:1098
#9  0x00007f24796ad4a8 in QWidget::event (this=0x3eac420, event=0x7fffae44afe0) at kernel/qwidget.cpp:8200
#10 0x00007f2479a9b9fb in QMenu::event (this=0x3eac420, e=0x7fffae44afe0) at widgets/qmenu.cpp:2410
#11 0x00007f247965bcd4 in QApplicationPrivate::notify_helper (this=0x7ef310, receiver=0x3eac420, e=0x7fffae44afe0) at kernel/qapplication.cpp:4445
#12 0x00007f2479664a4a in QApplication::notify (this=<value optimized out>, receiver=0x3eac420, e=0x7fffae44afe0) at kernel/qapplication.cpp:4006
#13 0x00007f247bbfeec6 in KApplication::notify (this=0x7fffae44d440, receiver=0x3eac420, event=0x7fffae44afe0) at /usr/src/debug/kdelibs-4.6.0/kdeui/kernel/kapplication.cpp:311
#14 0x00007f247a29de2c in QCoreApplication::notifyInternal (this=0x7fffae44d440, receiver=0x3eac420, event=0x7fffae44afe0) at kernel/qcoreapplication.cpp:732
#15 0x00007f247965ccd5 in sendEvent (receiver=0x3eac420, event=0x7fffae44afe0, alienWidget=0x0, nativeWidget=0x3eac420, buttonDown=0x7f247a137178, lastMouseReceiver=..., spontaneous=true)
    at ../../src/corelib/kernel/qcoreapplication.h:215
#16 QApplicationPrivate::sendMouseEvent (receiver=0x3eac420, event=0x7fffae44afe0, alienWidget=0x0, nativeWidget=0x3eac420, buttonDown=0x7f247a137178, lastMouseReceiver=..., spontaneous=true)
    at kernel/qapplication.cpp:3105
#17 0x00007f24796db144 in QETWidget::translateMouseEvent (this=0x3eac420, event=<value optimized out>) at kernel/qapplication_x11.cpp:4372
#18 0x00007f24796d95d9 in QApplication::x11ProcessEvent (this=0x7fffae44d440, event=0x7fffae44b940) at kernel/qapplication_x11.cpp:3564
#19 0x00007f2479701212 in x11EventSourceDispatch (s=0x7f4ca0, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#20 0x00007f2472356a93 in g_main_dispatch (context=0x7f6a60) at gmain.c:1960
#21 IA__g_main_context_dispatch (context=0x7f6a60) at gmain.c:2513
#22 0x00007f2472357270 in g_main_context_iterate (context=0x7f6a60, block=1, dispatch=1, self=<value optimized out>) at gmain.c:2591
#23 0x00007f2472357510 in IA__g_main_context_iteration (context=0x7f6a60, may_block=1) at gmain.c:2654
#24 0x00007f247a2c8a8f in QEventDispatcherGlib::processEvents (this=0x66c520, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:422
#25 0x00007f2479700eae in QGuiEventDispatcherGlib::processEvents (this=<value optimized out>, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:204
#26 0x00007f247a29d262 in QEventLoop::processEvents (this=<value optimized out>, flags=...) at kernel/qeventloop.cpp:149
#27 0x00007f247a29d475 in QEventLoop::exec (this=0x7fffae44bc60, flags=...) at kernel/qeventloop.cpp:201
#28 0x00007f2479a97f75 in QMenu::exec (this=<value optimized out>, p=..., action=0x0) at widgets/qmenu.cpp:2054
#29 0x00007f2479aa62f2 in QPushButtonPrivate::_q_popupPressed (this=0x941a10) at widgets/qpushbutton.cpp:592
#30 0x00007f2479aa6a82 in QPushButton::qt_metacall (this=0x2116ad0, _c=QMetaObject::InvokeMetaMethod, _id=1, _a=0x7fffae44bdd0) at .moc/release-shared/moc_qpushbutton.cpp:80
#31 0x00007f247b38d1e8 in Amarok::ElidingButton::qt_metacall (this=0x2116ad0, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=<value optimized out>)
    at /usr/src/debug/amarok-2.4.0/build/src/ElidingButton.moc:67
#32 0x00007f247a2b2fef in QMetaObject::activate (sender=0x2116ad0, m=<value optimized out>, local_signal_index=<value optimized out>, argv=0x0) at kernel/qobject.cpp:3272
#33 0x00007f2479a177be in QAbstractButtonPrivate::emitPressed (this=0x941a10) at widgets/qabstractbutton.cpp:560
#34 0x00007f2479a1823c in QAbstractButton::mousePressEvent (this=0x2116ad0, e=0x7fffae44c750) at widgets/qabstractbutton.cpp:1096
#35 0x00007f24796ad799 in QWidget::event (this=0x2116ad0, event=0x7fffae44c750) at kernel/qwidget.cpp:8196
#36 0x00007f247965bcd4 in QApplicationPrivate::notify_helper (this=0x7ef310, receiver=0x2116ad0, e=0x7fffae44c750) at kernel/qapplication.cpp:4445
#37 0x00007f2479664a4a in QApplication::notify (this=<value optimized out>, receiver=0x2116ad0, e=0x7fffae44c750) at kernel/qapplication.cpp:4006
#38 0x00007f247bbfeec6 in KApplication::notify (this=0x7fffae44d440, receiver=0x2116ad0, event=0x7fffae44c750) at /usr/src/debug/kdelibs-4.6.0/kdeui/kernel/kapplication.cpp:311
#39 0x00007f247a29de2c in QCoreApplication::notifyInternal (this=0x7fffae44d440, receiver=0x2116ad0, event=0x7fffae44c750) at kernel/qcoreapplication.cpp:732
#40 0x00007f247965ccd5 in sendEvent (receiver=0x2116ad0, event=0x7fffae44c750, alienWidget=0x2116ad0, nativeWidget=0xd4d8f0, buttonDown=0x7f247a137178, lastMouseReceiver=..., spontaneous=true)
    at ../../src/corelib/kernel/qcoreapplication.h:215
#41 QApplicationPrivate::sendMouseEvent (receiver=0x2116ad0, event=0x7fffae44c750, alienWidget=0x2116ad0, nativeWidget=0xd4d8f0, buttonDown=0x7f247a137178, lastMouseReceiver=..., spontaneous=true)
    at kernel/qapplication.cpp:3105
#42 0x00007f24796daef8 in QETWidget::translateMouseEvent (this=0xd4d8f0, event=<value optimized out>) at kernel/qapplication_x11.cpp:4438
#43 0x00007f24796d95d9 in QApplication::x11ProcessEvent (this=0x7fffae44d440, event=0x7fffae44d0b0) at kernel/qapplication_x11.cpp:3564
#44 0x00007f2479701212 in x11EventSourceDispatch (s=0x7f4ca0, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#45 0x00007f2472356a93 in g_main_dispatch (context=0x7f6a60) at gmain.c:1960
#46 IA__g_main_context_dispatch (context=0x7f6a60) at gmain.c:2513
#47 0x00007f2472357270 in g_main_context_iterate (context=0x7f6a60, block=1, dispatch=1, self=<value optimized out>) at gmain.c:2591
#48 0x00007f2472357510 in IA__g_main_context_iteration (context=0x7f6a60, may_block=1) at gmain.c:2654
#49 0x00007f247a2c8a8f in QEventDispatcherGlib::processEvents (this=0x66c520, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:422
#50 0x00007f2479700eae in QGuiEventDispatcherGlib::processEvents (this=<value optimized out>, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:204
#51 0x00007f247a29d262 in QEventLoop::processEvents (this=<value optimized out>, flags=...) at kernel/qeventloop.cpp:149
#52 0x00007f247a29d475 in QEventLoop::exec (this=0x7fffae44d3d0, flags=...) at kernel/qeventloop.cpp:201
#53 0x00007f247a2a18db in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1009
#54 0x000000000040960d in main (argc=1, argv=0x7fffae44f8b8) at /usr/src/debug/amarok-2.4.0/src/main.cpp:268

Possible duplicates by query: bug 265626, bug 245004, bug 242085, bug 241161, bug 238040.

Reported using DrKonqi

*** Bug 271372 has been marked as a duplicate of this bug. ***

Developers, please see also line #21 in https://bugs.kde.org/show_bug.cgi?id=271372#c4

*** Bug 273210 has been marked as a duplicate of this bug. ***

Could you all please upgrade to Amarok 2.4.1 and try again?

2.4.1 is not available even in Kubuntu 11.04 repositories. If you have a pre built package somewhere for Kubuntu 10.10 or 11.04, I'll appreciate passing it on. 

Compilation from source will take some time as I have to setup the build environment.

Dev Gai: please see here: http://kubuntu.org/news/

Reproducible.
See GDB backtrace.
===================
bug265626_bt_amarok2.4.1
------------------------
#0  QMetaObject::changeGuard (ptr=0x91ccc78, o=0x0) at kernel/qobject.cpp:471
#1  0x016ea193 in operator= (this=0x91ccad8, action=0x91c54b0, action_e=QAction::Trigger, self=true) at ../../include/QtCore/../../src/corelib/kernel/qpointer.h:68
#2  QMenuPrivate::activateAction (this=0x91ccad8, action=0x91c54b0, action_e=QAction::Trigger, self=true) at widgets/qmenu.cpp:1098
#3  0x016eaffe in QMenu::mouseReleaseEvent (this=0x91bd168, e=0xbfffd044) at widgets/qmenu.cpp:2306
#4  0x012b113a in QWidget::event (this=0x91bd168, event=0xbfffd044) at kernel/qwidget.cpp:8259
#5  0x016eb4d7 in QMenu::event (this=0x91bd168, e=0xbfffd044) at widgets/qmenu.cpp:2415
#6  0x01258d24 in QApplicationPrivate::notify_helper (this=0x819fee0, receiver=0x91bd168, e=0xbfffd044) at kernel/qapplication.cpp:4462
#7  0x0125e201 in QApplication::notify (this=0xbfffe984, receiver=0x91bd168, e=0xbfffd044) at kernel/qapplication.cpp:4023
#8  0x003103ca in KApplication::notify (this=0xbfffe984, receiver=0x91bd168, event=0xbfffd044) at ../../kdeui/kernel/kapplication.cpp:311
#9  0x01f700bb in QCoreApplication::notifyInternal (this=0xbfffe984, receiver=0x91bd168, event=0xbfffd044) at kernel/qcoreapplication.cpp:731
#10 0x01259c3b in sendSpontaneousEvent (receiver=0x91bd168, event=0xbfffd044, alienWidget=0x0, nativeWidget=0x91bd168, buttonDown=0x1ba5c60, lastMouseReceiver=..., 
    spontaneous=true) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:218
#11 QApplicationPrivate::sendMouseEvent (receiver=0x91bd168, event=0xbfffd044, alienWidget=0x0, nativeWidget=0x91bd168, buttonDown=0x1ba5c60, lastMouseReceiver=..., 
    spontaneous=true) at kernel/qapplication.cpp:3120
#12 0x012e34c3 in QETWidget::translateMouseEvent (this=0x91bd168, event=0xbfffd56c) at kernel/qapplication_x11.cpp:4490
#13 0x012e1746 in QApplication::x11ProcessEvent (this=0xbfffe984, event=0xbfffd56c) at kernel/qapplication_x11.cpp:3678
#14 0x0130cb84 in x11EventSourceDispatch (s=0x81a1a00, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#15 0x033e5aa8 in g_main_dispatch (context=0x819fd00) at /build/buildd/glib2.0-2.28.6/./glib/gmain.c:2440
#16 g_main_context_dispatch (context=0x819fd00) at /build/buildd/glib2.0-2.28.6/./glib/gmain.c:3013
#17 0x033e6270 in g_main_context_iterate (context=0x819fd00, block=54487072, dispatch=1, self=<value optimized out>) at /build/buildd/glib2.0-2.28.6/./glib/gmain.c:3091
#18 0x033e6524 in g_main_context_iteration (context=0x819fd00, may_block=1) at /build/buildd/glib2.0-2.28.6/./glib/gmain.c:3154
#19 0x01f9d53c in QEventDispatcherGlib::processEvents (this=0x8078eb0, flags=...) at kernel/qeventdispatcher_glib.cpp:422
#20 0x0130c775 in QGuiEventDispatcherGlib::processEvents (this=0x8078eb0, flags=...) at kernel/qguieventdispatcher_glib.cpp:204
#21 0x01f6f289 in QEventLoop::processEvents (this=0xbfffd840, flags=...) at kernel/qeventloop.cpp:149
#22 0x01f6f522 in QEventLoop::exec (this=0xbfffd840, flags=...) at kernel/qeventloop.cpp:201
#23 0x016e75c1 in QMenu::exec (this=0x91bd168, p=..., action=0x0) at widgets/qmenu.cpp:2059
#24 0x016f7d11 in QPushButtonPrivate::_q_popupPressed (this=0x91ccf60) at widgets/qpushbutton.cpp:592
#25 0x016f8507 in QPushButton::qt_metacall (this=0x91cce28, _c=QMetaObject::InvokeMetaMethod, _id=1, _a=0xbfffd9cc) at .moc/release-shared/moc_qpushbutton.cpp:80
#26 0x00dbcf2a in Amarok::ElidingButton::qt_metacall (this=0x91cce28, _c=QMetaObject::InvokeMetaMethod, _id=40, _a=0xbfffd9cc) at ./ElidingButton.moc:67
#27 0x00db4622 in qt_metacall (this=0x91cce28, _c=QMetaObject::InvokeMetaMethod, _id=40, _a=0xbfffd9cc) at ./BreadcrumbItemButton.moc:66
#28 BreadcrumbItemMenuButton::qt_metacall (this=0x91cce28, _c=QMetaObject::InvokeMetaMethod, _id=40, _a=0xbfffd9cc) at ./BreadcrumbItemButton.moc:115
#29 0x01f766ba in QMetaObject::metacall (object=0x91cce28, cl=QMetaObject::InvokeMetaMethod, idx=40, argv=0xbfffd9cc) at kernel/qmetaobject.cpp:237
#30 0x01f864ff in QMetaObject::activate (sender=0x91cce28, m=0x1b9c884, local_signal_index=0, argv=0x0) at kernel/qobject.cpp:3287
#31 0x01941ca7 in QAbstractButton::pressed (this=0x91cce28) at .moc/release-shared/moc_qabstractbutton.cpp:193
#32 0x01659946 in QAbstractButtonPrivate::emitPressed (this=0x91ccf60) at widgets/qabstractbutton.cpp:560
#33 0x0165a5be in QAbstractButton::mousePressEvent (this=0x91cce28, e=0xbfffe104) at widgets/qabstractbutton.cpp:1096
#34 0x012b12ec in QWidget::event (this=0x91cce28, event=0xbfffe104) at kernel/qwidget.cpp:8255
#35 0x0165a40e in QAbstractButton::event (this=0x91cce28, e=0xbfffe104) at widgets/qabstractbutton.cpp:1080
#36 0x016f81c2 in QPushButton::event (this=0x91cce28, e=0xbfffe104) at widgets/qpushbutton.cpp:683
#37 0x01258d24 in QApplicationPrivate::notify_helper (this=0x819fee0, receiver=0x91cce28, e=0xbfffe104) at kernel/qapplication.cpp:4462
#38 0x0125e201 in QApplication::notify (this=0xbfffe984, receiver=0x91cce28, e=0xbfffe104) at kernel/qapplication.cpp:4023
#39 0x003103ca in KApplication::notify (this=0xbfffe984, receiver=0x91cce28, event=0xbfffe104) at ../../kdeui/kernel/kapplication.cpp:311
#40 0x01f700bb in QCoreApplication::notifyInternal (this=0xbfffe984, receiver=0x91cce28, event=0xbfffe104) at kernel/qcoreapplication.cpp:731
#41 0x01259c3b in sendSpontaneousEvent (receiver=0x91cce28, event=0xbfffe104, alienWidget=0x91cce28, nativeWidget=0x857aa70, buttonDown=0x1ba5c60, lastMouseReceiver=..., 
    spontaneous=true) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:218
---Type <return> to continue, or q <return> to quit---
#42 QApplicationPrivate::sendMouseEvent (receiver=0x91cce28, event=0xbfffe104, alienWidget=0x91cce28, nativeWidget=0x857aa70, buttonDown=0x1ba5c60, lastMouseReceiver=..., 
    spontaneous=true) at kernel/qapplication.cpp:3120
#43 0x012e32bc in QETWidget::translateMouseEvent (this=0x857aa70, event=0xbfffe62c) at kernel/qapplication_x11.cpp:4556
#44 0x012e1746 in QApplication::x11ProcessEvent (this=0xbfffe984, event=0xbfffe62c) at kernel/qapplication_x11.cpp:3678
#45 0x0130cb84 in x11EventSourceDispatch (s=0x81a1a00, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#46 0x033e5aa8 in g_main_dispatch (context=0x819fd00) at /build/buildd/glib2.0-2.28.6/./glib/gmain.c:2440
#47 g_main_context_dispatch (context=0x819fd00) at /build/buildd/glib2.0-2.28.6/./glib/gmain.c:3013
#48 0x033e6270 in g_main_context_iterate (context=0x819fd00, block=54487072, dispatch=1, self=<value optimized out>) at /build/buildd/glib2.0-2.28.6/./glib/gmain.c:3091
#49 0x033e6524 in g_main_context_iteration (context=0x819fd00, may_block=1) at /build/buildd/glib2.0-2.28.6/./glib/gmain.c:3154
#50 0x01f9d53c in QEventDispatcherGlib::processEvents (this=0x8078eb0, flags=...) at kernel/qeventdispatcher_glib.cpp:422
#51 0x0130c775 in QGuiEventDispatcherGlib::processEvents (this=0x8078eb0, flags=...) at kernel/qguieventdispatcher_glib.cpp:204
#52 0x01f6f289 in QEventLoop::processEvents (this=0xbfffe8f4, flags=...) at kernel/qeventloop.cpp:149
#53 0x01f6f522 in QEventLoop::exec (this=0xbfffe8f4, flags=...) at kernel/qeventloop.cpp:201
#54 0x01f73ecc in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1008
#55 0x012568e7 in QApplication::exec () at kernel/qapplication.cpp:3736
#56 0x08050e3d in main (argc=0, argv=0x8a87948) at ../../src/main.cpp:288

Thank you for the feedback.

*** Bug 274115 has been marked as a duplicate of this bug. ***

Created attachment 61190 [details]
New crash information added by DrKonqi

amarok (2.4.1) on KDE Platform 4.6.4 (4.6.4) using Qt 4.7.3

- What I was doing when the application crashed:
I browsed files in the left drop-down menu and when I clicked on an entry, Amarok crashed.

-- Backtrace (Reduced):
#7  0x00007f7f3226e05e in operator= (this=0x1fac0e0, action=0x20a5ec0, action_e=QAction::Trigger, self=true) at ../../src/corelib/kernel/qpointer.h:68
#8  QMenuPrivate::activateAction (this=0x1fac0e0, action=0x20a5ec0, action_e=QAction::Trigger, self=true) at widgets/qmenu.cpp:1098
#9  0x00007f7f31e88c5c in QWidget::event (this=0x1b7dfd0, event=0x7fffd8ae6390) at kernel/qwidget.cpp:8259
#10 0x00007f7f3226f22b in QMenu::event (this=0x1b7dfd0, e=0x7fffd8ae6390) at widgets/qmenu.cpp:2415
#11 0x00007f7f31e37144 in QApplicationPrivate::notify_helper (this=0x7ef310, receiver=0x1b7dfd0, e=0x7fffd8ae6390) at kernel/qapplication.cpp:4462

*** Bug 276868 has been marked as a duplicate of this bug. ***

*** Bug 278633 has been marked as a duplicate of this bug. ***

Created attachment 62746 [details]
New crash information added by DrKonqi

amarok (2.4.0) on KDE Platform 4.6.2 (4.6.2) using Qt 4.7.2

- What I was doing when the application crashed:
I chose another folder by clicking on an arrow.
- Custom settings of the application:
I use MySQL 5.x

-- Backtrace (Reduced):
#8  0x047bbc23 in operator= (this=0x987a520, action=0x9a2ebd0, action_e=QAction::Trigger, self=true) at ../../include/QtCore/../../src/corelib/kernel/qpointer.h:68
#9  QMenuPrivate::activateAction (this=0x987a520, action=0x9a2ebd0, action_e=QAction::Trigger, self=true) at widgets/qmenu.cpp:1098
#10 0x047bca8e in QMenu::mouseReleaseEvent (this=0x9a2ebf8, e=0xbfc2dfe4) at widgets/qmenu.cpp:2306
#11 0x0438013a in QWidget::event (this=0x9a2ebf8, event=0xbfc2dfe4) at kernel/qwidget.cpp:8259
#12 0x047bcf67 in QMenu::event (this=0x9a2ebf8, e=0xbfc2dfe4) at widgets/qmenu.cpp:2415

Created attachment 62789 [details]
New crash information added by DrKonqi

amarok (2.4.0) on KDE Platform 4.6.2 (4.6.2) using Qt 4.7.2

- What I was doing when the application crashed:
I was browsing files using the emplacement toolbar arrow widget, and I selected a file to display then amarok crashed.

-- Backtrace (Reduced):
#8  0x025f6c23 in operator= (this=0xbf5a760, action=0x989d630, action_e=QAction::Trigger, self=true) at ../../include/QtCore/../../src/corelib/kernel/qpointer.h:68
#9  QMenuPrivate::activateAction (this=0xbf5a760, action=0x989d630, action_e=QAction::Trigger, self=true) at widgets/qmenu.cpp:1098
#10 0x025f7a8e in QMenu::mouseReleaseEvent (this=0x8d809e8, e=0xbfeb6834) at widgets/qmenu.cpp:2306
#11 0x021bb13a in QWidget::event (this=0x8d809e8, event=0xbfeb6834) at kernel/qwidget.cpp:8259
#12 0x025f7f67 in QMenu::event (this=0x8d809e8, e=0xbfeb6834) at widgets/qmenu.cpp:2415

Created attachment 62791 [details]
New crash information added by DrKonqi

amarok (2.4.0) on KDE Platform 4.6.2 (4.6.2) using Qt 4.7.2

- What I was doing when the application crashed:
I was in my local folders when I left-clicked on the ">"  character between directory items and then Amarok crashed.  I tried it again afterwards and it opened up a dialog window to choose directories.  So, it only happened once (so far).

-- Backtrace (Reduced):
#7  0x00007f5a836859ce in operator= (this=0x7f5a58731230, action=0x7f5a586efb10, action_e=QAction::Trigger, self=true) at ../../include/QtCore/../../src/corelib/kernel/qpointer.h:68
#8  QMenuPrivate::activateAction (this=0x7f5a58731230, action=0x7f5a586efb10, action_e=QAction::Trigger, self=true) at widgets/qmenu.cpp:1098
#9  0x00007f5a83292cc8 in QWidget::event (this=0x7f5a586f4f70, event=0x7fff842cc100) at kernel/qwidget.cpp:8259
#10 0x00007f5a83686b8b in QMenu::event (this=0x7f5a586f4f70, e=0x7fff842cc100) at widgets/qmenu.cpp:2415
#11 0x00007f5a832419f4 in QApplicationPrivate::notify_helper (this=0x11c5d80, receiver=0x7f5a586f4f70, e=0x7fff842cc100) at kernel/qapplication.cpp:4462

*** Bug 281897 has been marked as a duplicate of this bug. ***

*** Bug 282501 has been marked as a duplicate of this bug. ***

Created attachment 64047 [details]
New crash information added by DrKonqi

amarok (2.4.0) on KDE Platform 4.6.2 (4.6.2) using Qt 4.7.2

- What I was doing when the application crashed:
I was browsing between "mp3" files. I opened a folder without problems, but when I opened a second folder, Amarok crashed.

-- Backtrace (Reduced):
#8  0x022cac23 in operator= (this=0xb34cde8, action=0xb33c2a8, action_e=QAction::Trigger, self=true) at ../../include/QtCore/../../src/corelib/kernel/qpointer.h:68
#9  QMenuPrivate::activateAction (this=0xb34cde8, action=0xb33c2a8, action_e=QAction::Trigger, self=true) at widgets/qmenu.cpp:1098
#10 0x022cba8e in QMenu::mouseReleaseEvent (this=0xaf2e1f8, e=0xbf9b11e4) at widgets/qmenu.cpp:2306
#11 0x01e8f13a in QWidget::event (this=0xaf2e1f8, event=0xbf9b11e4) at kernel/qwidget.cpp:8259
#12 0x022cbf67 in QMenu::event (this=0xaf2e1f8, e=0xbf9b11e4) at widgets/qmenu.cpp:2415

Created attachment 64390 [details]
New crash information added by DrKonqi

amarok (2.4.0) on KDE Platform 4.6.00 (4.6.0) "release 6" using Qt 4.7.1

- What I was doing when the application crashed:

As in comment 2:
- Clicking on symbol ">" in breadcrumb control line: OK
- opening of list of possible directories: OK
- selecting one entry (same one as the present directory has been): crash

-- Backtrace (Reduced):
#7  0x00007faab820de9e in operator= (this=0x256cfa0, action=0x24f5d70, action_e=QAction::Trigger, self=true) at ../../src/corelib/kernel/qpointer.h:68
#8  QMenuPrivate::activateAction (this=0x256cfa0, action=0x24f5d70, action_e=QAction::Trigger, self=true) at widgets/qmenu.cpp:1098
#9  0x00007faab7e29538 in QWidget::event (this=0x2293c70, event=0x7fff02147350) at kernel/qwidget.cpp:8200
#10 0x00007faab820f06b in QMenu::event (this=0x2293c70, e=0x7fff02147350) at widgets/qmenu.cpp:2410
#11 0x00007faab7dd7d14 in QApplicationPrivate::notify_helper (this=0x7a6f50, receiver=0x2293c70, e=0x7fff02147350) at kernel/qapplication.cpp:4445

Can somebody please test with the latest 2.4.3 or the 2.5 beta version?

Tested with Amarok 2.5-git, Qt 4.7.4 and KDE 4.8 RC1, I see no evidence of Amarok being the culprit in the backtrace. Maybe a Qt issue?

Thread 1 (Thread 0x7fd2b43af7a0 (LWP 1793)):
[KCrash Handler]
#6  QBoxLayout::hasHeightForWidth (this=0x35a8c80) at kernel/qboxlayout.cpp:714
#7  0x00007fd2b24fc8f2 in QBoxLayoutPrivate::setupGeom (this=0x305e400) at kernel/qboxlayout.cpp:388
#8  0x00007fd2b24fd39d in QBoxLayout::setGeometry (this=0x305e3d0, r=...) at kernel/qboxlayout.cpp:817
#9  0x00007fd2b2517d73 in QLayoutPrivate::doResize (this=0x305e400, r=...) at kernel/qlayout.cpp:681
#10 0x00007fd2b2519451 in QLayout::activate (this=0x305e3d0) at kernel/qlayout.cpp:1259
#11 0x00007fd2b24ee3e1 in notify_helper (e=0x5c02fe0, receiver=0x305bfe0, this=0x1fdb1e0) at kernel/qapplication.cpp:4477
#12 QApplicationPrivate::notify_helper (this=0x1fdb1e0, receiver=0x305bfe0, e=0x5c02fe0) at kernel/qapplication.cpp:4458
#13 0x00007fd2b24f3291 in QApplication::notify (this=0x7fff32b577e0, receiver=0x305bfe0, e=0x5c02fe0) at kernel/qapplication.cpp:4365
#14 0x00007fd2b3ee1a46 in KApplication::notify (this=0x7fff32b577e0, receiver=0x305bfe0, event=0x5c02fe0) at ../../kdeui/kernel/kapplication.cpp:311
#15 0x00007fd2b1aedafc in QCoreApplication::notifyInternal (this=0x7fff32b577e0, receiver=0x305bfe0, event=0x5c02fe0) at kernel/qcoreapplication.cpp:787
#16 0x00007fd2b1af151f in sendEvent (event=0x5c02fe0, receiver=0x305bfe0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#17 QCoreApplicationPrivate::sendPostedEvents (receiver=0x0, event_type=0, data=0x1e12430) at kernel/qcoreapplication.cpp:1428
#18 0x00007fd2b1b18a73 in sendPostedEvents () at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:220
#19 postEventSourceDispatch (s=<optimized out>) at kernel/qeventdispatcher_glib.cpp:277
#20 0x00007fd2ab31fa5d in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#21 0x00007fd2ab320258 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#22 0x00007fd2ab320429 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#23 0x00007fd2b1b18ed6 in QEventDispatcherGlib::processEvents (this=0x1e13f40, flags=<optimized out>) at kernel/qeventdispatcher_glib.cpp:422
#24 0x00007fd2b259607e in QGuiEventDispatcherGlib::processEvents (this=<optimized out>, flags=<optimized out>) at kernel/qguieventdispatcher_glib.cpp:204
#25 0x00007fd2b1aeccf2 in QEventLoop::processEvents (this=<optimized out>, flags=...) at kernel/qeventloop.cpp:149
#26 0x00007fd2b1aecef7 in QEventLoop::exec (this=0x7fff32b57760, flags=...) at kernel/qeventloop.cpp:201
#27 0x00007fd2b1af1789 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1064
#28 0x000000000040c7e4 in main (argc=3, argv=0x7fff32b59c58) at /home/myriam/kde/src/amarok/src/main.cpp:303

*** Bug 301916 has been marked as a duplicate of this bug. ***

The latest backtrace doesn't show the function call from amarok but only the Qt and KDE functions. Might be a problem higher up in the stack. Any ideas

(In reply to comment #28)
> The latest backtrace doesn't show the function call from amarok but only the
> Qt and KDE functions. Might be a problem higher up in the stack. Any ideas?

Subscribing David who might have a hint for us.

Created attachment 73556 [details]
New crash information added by DrKonqi

amarok (2.5.0) on KDE Platform 4.8.4 (4.8.4) using Qt 4.8.1

- What I was doing when the application crashed:

Started amarok; from the last session, "file browser" was opened and located in the directory where I was listening the last time.

I clicked on the arrow between directories two levels up, and selected a directory from the quick-selection popup.

In that moment, Amarok crashed.

-- Backtrace (Reduced):
#7  0x00007f51bc42c296 in operator= (p=0x0, this=0x2564ce0) at ../../include/QtCore/../../src/corelib/kernel/qpointer.h:68
#8  QMenuPrivate::activateAction (this=0x2564a20, action=0x256dd60, action_e=QAction::Trigger, self=true) at widgets/qmenu.cpp:1133
#9  0x00007f51bc02b144 in QWidget::event (this=0x22ed0b0, event=0x7fff4b737e10) at kernel/qwidget.cpp:8362
#10 0x00007f51bc42d80b in QMenu::event (this=0x22ed0b0, e=0x7fff4b737e10) at widgets/qmenu.cpp:2469
#11 0x00007f51bbfda894 in notify_helper (e=0x7fff4b737e10, receiver=0x22ed0b0, this=0x94c830) at kernel/qapplication.cpp:4559

Same bug, Qt 4.8.3, Amarok 2.6: http://paste.kde.org/581594/

I think this is because of the use of QMenu::exec() in the bread crumb. This re-enters the event loop, and then it gets caught up with events related to mouse events.

The bug is for whoever owns the bread crumb code. I don't think it's possible to use QMenu::exec() safely. Synchronous API calls for non-synchronous events are evil.

Created attachment 74818 [details]
patch to possibly fix a related crash

So I've been looking into the issue in the morning. I found a new crash that I think is unrelated to the main issue; the patch for that is attached. I'm hesitant to submit it because it doesn't actually fix the crash caused by messing with the bread crumb widget.

This is what I think is happening:
The Amarok bread crumb widget uses QPushButton.setMenu. Unfortunately QPushButton uses QMenu::exec, which is an synchronous function which commits evil and dips into the eventloop (QPushButton uses it even though it doesn't even use the QAction that it returns!). It gets all confused when it goes into the event loop and then QMenu deletes itself somewhere along way and crashes. 

So we should think about filing a Qt bug, but it's possible I'm not reading the qmenu.cpp code correctly. 

For Amarok the fix for the bug is probably to not use QPushButton.setMenu.

Ian: good analysis, patch looks ok to me (the comment is redundant though) ;)

This is the same issue as in bug 249884 (which has a valgrind log), where it was also "worked around" in KDE core, not fixed in Qt.

Since then I added this to my ever-growing todo list:
"QMenu crashes when deleted from one of its actions. bug 249884, RecursionGuard member accessed after deletion, weakpointer guard needed."

Created attachment 75396 [details]
New crash information added by DrKonqi

amarok (2.6.0) on KDE Platform 4.9.2 using Qt 4.8.3

- What I was doing when the application crashed:

I was navigating through the Breadcrumb (option: "organize library by folders"): whenever I click on the arrow that displays the "same-level-folders" and I click on one of them, Amarok crashes with segmentation fault.

My music is organized this way
Country -> Artist -> Album -> Songs.mp3

So, if I was on the folder
Argentina -> Martin Knye Magiar -> Twister

And I wanted to play some artist from Inglaterra (England), so I clicked on the arrow previous to "Argentina", it displayed all the other countrys (Inglaterra, Chile, Brasil, etc) and when I click on "Inglaterra" from this "pop-up" window, amarok crashes with segmentation fault

This bug happens when I'm on no matter what folder, and I want to change to no matter what folder from the Breadcrumb.

Cheers

-- Backtrace (Reduced):
#7  0x00007fa4fedc16dd in operator= (p=0x0, this=0x3b22b30) at ../../include/QtCore/../../src/corelib/kernel/qpointer.h:68
#8  QMenuPrivate::activateAction (this=0x3b22870, action=0x3b12d80, action_e=QAction::Trigger, self=<optimized out>) at widgets/qmenu.cpp:1133
#9  0x00007fa4fe9d2850 in QWidget::event (this=0x3b2aa40, event=0x7fff936be800) at kernel/qwidget.cpp:8371
#10 0x00007fa4fedc296b in QMenu::event (this=0x3b2aa40, e=0x7fff936be800) at widgets/qmenu.cpp:2469
#11 0x00007fa4fe982e9c in QApplicationPrivate::notify_helper (this=this@entry=0x10a3710, receiver=receiver@entry=0x3b2aa40, e=e@entry=0x7fff936be800) at kernel/qapplication.cpp:4562

I can reproduce this on v2.6.0-421-gf66a306

Git commit 330c47a1ec32a1f5779dd96a2ab522602a65e910 by Matěj Laitl, on behalf of Ian Monroe.
Committed on 26/10/2012 at 22:04.
Pushed by laitl into branch 'master'.

Use QObject for memory management of QMenu's

Commited Ian's patch, it cannot hurt. Quite surprisingly, it fixes bug
265626 for me. I.e I was able to reproduce every time before the patch,
not a single time after applying the patch.

Original reporters and testers: please test that this really fixes it.
FIXED-IN: 2.7

M  +1    -0    ChangeLog
M  +3    -5    src/browsers/BrowserBreadcrumbItem.cpp

http://commits.kde.org/amarok/330c47a1ec32a1f5779dd96a2ab522602a65e910

Reopening, able to reproduce now.

*** Bug 298836 has been marked as a duplicate of this bug. ***

*** Bug 308394 has been marked as a duplicate of this bug. ***

Git commit 80bb50d8fcf9cdc3cd27050f9828e4fec91ada49 by Matěj Laitl.
Committed on 04/01/2013 at 22:00.
Pushed by laitl into branch 'master'.

BrowserCategory: (hopefully) definitely fix crash bug 265626

The cause is in the code comments.
FIXED-IN: 2.7
CCMAIL: Ian Monroe <ian.monroe@gmail.com>

M  +1    -1    ChangeLog
M  +5    -2    src/browsers/BrowserCategory.cpp
M  +5    -1    src/browsers/BrowserCategory.h

http://commits.kde.org/amarok/80bb50d8fcf9cdc3cd27050f9828e4fec91ada49