Version:            (using KDE Devel)
Installed from:    Compiled sources

Was switching to the next (very large) image in Kuickshow when kwin crashed. Here is the bt:

Using host libthread_db library "/lib64/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread 46912542296800 (LWP 30743)]
[KCrash handler]
#5  0x0000003266830ec5 in raise () from /lib64/libc.so.6
#6  0x0000003266832970 in abort () from /lib64/libc.so.6
#7  0x00002aaaab8e2a58 in qt_message_output (msgType=QtFatalMsg, 
    buf=0x7fff82cca820 "ASSERT: \"!( vertical && horizontal ) || ((( max_mode & MaximizeVertical ) != 0 ) == (( max_mode & MaximizeHorizontal ) != 0 ))\" in file /home/kde4/kdesvn/kdebase/workspace/kwin/geometry.cpp, line 1915")
    at /home/kde4/kdesvn/qt-copy/src/corelib/global/qglobal.cpp:2160
#8  0x00002aaaab8e2b67 in qFatal (
    msg=0x2aaaab9cfeb8 "ASSERT: \"%s\" in file %s, line %d")
    at /home/kde4/kdesvn/qt-copy/src/corelib/global/qglobal.cpp:2392
#9  0x00002aaaab8e2ca5 in qt_assert (
    assertion=0x2aaaaab59de8 "!( vertical && horizontal ) || ((( max_mode & MaximizeVertical ) != 0 ) == (( max_mode & MaximizeHorizontal ) != 0 ))", 
    file=0x2aaaaab59b30 "/home/kde4/kdesvn/kdebase/workspace/kwin/geometry.cpp", line=1915) at /home/kde4/kdesvn/qt-copy/src/corelib/global/qglobal.cpp:1917
#10 0x00002aaaaab245f3 in KWin::Client::changeMaximize (this=0xa137a0, 
    vertical=true, horizontal=true, adjust=false)
    at /home/kde4/kdesvn/kdebase/workspace/kwin/geometry.cpp:1914
#11 0x00002aaaaab25321 in KWin::Client::setMaximize (this=0xa137a0, 
    vertically=true, horizontally=false)
    at /home/kde4/kdesvn/kdebase/workspace/kwin/geometry.cpp:1889
#12 0x00002aaaaab25369 in KWin::Client::maximize (this=0xa137a0, 
    m=KDecorationDefines::MaximizeVertical)
    at /home/kde4/kdesvn/kdebase/workspace/kwin/geometry.cpp:1878
#13 0x00002aaaaab25665 in KWin::Client::checkMaximizeGeometry (this=0xa137a0)
    at /home/kde4/kdesvn/kdebase/workspace/kwin/geometry.cpp:2109
#14 0x00002aaaaab22030 in KWin::Client::setGeometry (this=0xa137a0, x=0, y=0, 
    w=1266, h=968, force=KWin::NormalGeometrySet)
    at /home/kde4/kdesvn/kdebase/workspace/kwin/geometry.cpp:1730
#15 0x00002aaaaaaea743 in KWin::Client::setGeometry (this=0xa137a0, 
    r=@0x7fff82cccfb0, force=KWin::NormalGeometrySet)
    at /home/kde4/kdesvn/kdebase/workspace/kwin/client.h:735
#16 0x00002aaaaab2408b in KWin::Client::blockGeometryUpdates (this=0xa137a0, 
    block=false) at /home/kde4/kdesvn/kdebase/workspace/kwin/geometry.cpp:1869
#17 0x00002aaaaaadcb91 in KWin::GeometryUpdatesBlocker::~GeometryUpdatesBlocker () at /home/kde4/qt4/include/QtCore/qdebug.h:81
#18 0x00002aaaaab295be in KWin::Client::configureRequest (this=0xa137a0, 
    value_mask=12, rx=0, ry=0, rw=1256, rh=938, gravity=1, from_tool=false)
    at /home/kde4/kdesvn/kdebase/workspace/kwin/geometry.cpp:1487
#19 0x00002aaaaaafe441 in KWin::Client::configureRequestEvent (this=0xa137a0, 
    e=0x7fff82ccdb80)
    at /home/kde4/kdesvn/kdebase/workspace/kwin/events.cpp:891
#20 0x00002aaaaaafef34 in KWin::Client::windowEvent (this=0xa137a0, 
    e=0x7fff82ccdb80)
    at /home/kde4/kdesvn/kdebase/workspace/kwin/events.cpp:630
#21 0x00002aaaaaaff7b8 in KWin::Workspace::workspaceEvent (this=0x755020, 
    e=0x7fff82ccdb80)
    at /home/kde4/kdesvn/kdebase/workspace/kwin/events.cpp:291
#22 0x00002aaaaaaf01a7 in KWin::Application::x11EventFilter (
    this=0x7fff82ccdf90, e=0x7fff82ccdb80)
    at /home/kde4/kdesvn/kdebase/workspace/kwin/main.cpp:278
#23 0x00002aaaac379508 in qt_x11EventFilter (ev=0x7fff82ccdb80)
    at /home/kde4/kdesvn/qt-copy/src/gui/kernel/qapplication_x11.cpp:346
#24 0x00002aaaac38326d in QApplication::x11ProcessEvent (this=0x7fff82ccdf90, 
    event=0x7fff82ccdb80)
    at /home/kde4/kdesvn/qt-copy/src/gui/kernel/qapplication_x11.cpp:2798
#25 0x00002aaaac3aff6b in x11EventSourceDispatch (s=0x6166a0, callback=0, 
    user_data=0x0)
    at /home/kde4/kdesvn/qt-copy/src/gui/kernel/qguieventdispatcher_glib.cpp:135
#26 0x000000352c42eea3 in g_main_context_dispatch ()
   from /lib64/libglib-2.0.so.0
#27 0x000000352c43219d in ?? () from /lib64/libglib-2.0.so.0
#28 0x000000352c4326ce in g_main_context_iteration ()
   from /lib64/libglib-2.0.so.0
#29 0x00002aaaab9c0956 in QEventDispatcherGlib::processEvents (this=0x612da0, 
    flags=@0x7fff82ccddf0)
    at /home/kde4/kdesvn/qt-copy/src/corelib/kernel/qeventdispatcher_glib.cpp:338
#30 0x00002aaaac3af80f in QGuiEventDispatcherGlib::processEvents (
    this=0x612da0, flags=@0x7fff82ccde40)
    at /home/kde4/kdesvn/qt-copy/src/gui/kernel/qguieventdispatcher_glib.cpp:191
#31 0x00002aaaab9966f9 in QEventLoop::processEvents (this=0x7fff82ccdef0, 
    flags=@0x7fff82ccdea0)
    at /home/kde4/kdesvn/qt-copy/src/corelib/kernel/qeventloop.cpp:140
#32 0x00002aaaab99684e in QEventLoop::exec (this=0x7fff82ccdef0, 
    flags=@0x7fff82ccdf00)
    at /home/kde4/kdesvn/qt-copy/src/corelib/kernel/qeventloop.cpp:182
#33 0x00002aaaab999be8 in QCoreApplication::exec ()
    at /home/kde4/kdesvn/qt-copy/src/corelib/kernel/qcoreapplication.cpp:759
#34 0x00002aaaac320300 in QApplication::exec ()
    at /home/kde4/kdesvn/qt-copy/src/gui/kernel/qapplication.cpp:3053
#35 0x00002aaaaaaf17ea in kdemain (argc=1, argv=0x7fff82cce468)
    at /home/kde4/kdesvn/kdebase/workspace/kwin/main.cpp:427
#36 0x00000000004008e3 in main (argc=1, argv=0x7fff82cce468)
    at /home/kde4/kdesvn/build/kdebase/workspace/kwin/kwin_dummy.cpp:3
#0  0x000000326689ac30 in __nanosleep_nocancel () from /lib64/libc.so.6