Application that crashed: kate
Version of the application: 3.3.1
KDE Version: 4.3.1 (KDE 4.3.1)
Qt Version: 4.5.1
Operating System: Linux 2.6.28-gentoo-r5 i686

What I was doing when the application crashed:
Only observed the crash once.  Not sure if I can reproduce.
While editing two XML files, I hit Ctrl-A, Ctrl-C to select all and copy.  Then I switched to another XML file in the same Kate session and hit Ctrl-A, Ctrl-V to select all and paste.  The crash occured when I hit Ctrl-V.

 -- Backtrace:
Application: Kate (kdeinit4), signal: Aborted
[KCrash Handler]
#6  0xffffe424 in __kernel_vsyscall ()
#7  0xb699d660 in *__GI_raise (sig=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
#8  0xb699ee98 in *__GI_abort () at abort.c:88
#9  0xb7f4a125 in qt_message_output (msgType=QtFatalMsg, buf=0x8d128b0 "ASSERT: \"false\" in file /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kate/view/kateviewinternal.cpp, line 336")
    at global/qglobal.cpp:2017
#10 0xb7f4a1e7 in qFatal (msg=0xb807c598 "ASSERT: \"%s\" in file %s, line %d") at global/qglobal.cpp:2216
#11 0xb7f4a2a5 in qt_assert (assertion=0xb288dee4 "false", file=0xb28aacec "/var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kate/view/kateviewinternal.cpp", line=336)
    at global/qglobal.cpp:1786
#12 0xb280224b in KateViewInternal::endPos (this=0x8c6f350) at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kate/view/kateviewinternal.cpp:336
#13 0xb280237c in KateViewInternal::endLine (this=0x8c6f350) at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kate/view/kateviewinternal.cpp:343
#14 0xb2807503 in KateViewInternal::scrollPos (this=0x8c6f350, c=@0xbfffa1b4, force=false, calledExternally=false)
    at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kate/view/kateviewinternal.cpp:491
#15 0xb2807ef7 in KateViewInternal::slotRegionVisibilityChangedAt (this=0x8c6f350, clear_cache=false) at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kate/view/kateviewinternal.cpp:706
#16 0xb2810e5c in KateViewInternal::qt_metacall (this=0x8c6f350, _c=QMetaObject::InvokeMetaMethod, _id=18, _a=0xbfffa2d8)
    at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1_build/kate/kateviewinternal.moc:137
#17 0xb80440a9 in QMetaObject::activate (sender=0x8bb1fc4, from_signal_index=<value optimized out>, to_signal_index=4, argv=0x0) at kernel/qobject.cpp:3108
#18 0xb8044652 in QMetaObject::activate (sender=0x8bb1fc4, m=0xb28bf72c, local_signal_index=0, argv=0xbfffa2d8) at kernel/qobject.cpp:3185
#19 0xb27e91ff in KateCodeFoldingTree::regionVisibilityChangedAt (this=0x8bb1fc4, _t1=8, _t2=false) at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1_build/kate/katecodefolding.moc:106
#20 0xb27e9615 in KateCodeFoldingTree::toggleRegionVisibility (this=0x8bb1fc4, line=8) at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kate/syntax/katecodefolding.cpp:1412
#21 0xb2781fea in KateDocument::editRemoveLine (this=0x8c7ea38, line=8, editSource=Kate::NoEditSource)
    at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kate/document/katedocument.cpp:1455
#22 0xb2785ad4 in KateDocument::removeText (this=0x8c7ea38, _range=@0xbfffa4ec, block=false) at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kate/document/katedocument.cpp:799
#23 0xb27f1e4a in KateView::removeSelectedText (this=0x8c668b8) at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kate/view/kateview.cpp:1749
#24 0xb27892f9 in KateDocument::paste (this=0x8c7ea38, view=0x8c668b8, mode=QClipboard::Clipboard) at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kate/document/katedocument.cpp:4033
#25 0xb27eec74 in KateView::paste (this=0x8c668b8) at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kate/view/kateview.cpp:2363
#26 0xb27ff400 in KateView::qt_metacall (this=0x8c668b8, _c=QMetaObject::InvokeMetaMethod, _id=15, _a=0xbfffa6dc)
    at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1_build/kate/kateview.moc:307
#27 0xb80440a9 in QMetaObject::activate (sender=0x8c87d18, from_signal_index=<value optimized out>, to_signal_index=6, argv=0x0) at kernel/qobject.cpp:3108
#28 0xb80443d0 in QMetaObject::activate (sender=0x8c87d18, m=0xb73d70e8, from_local_signal_index=1, to_local_signal_index=2, argv=0xbfffa6dc) at kernel/qobject.cpp:3205
#29 0xb6cf1bd1 in QAction::triggered (this=0x8c87d18, _t1=false) at .moc/release-shared/moc_qaction.cpp:236
#30 0xb6cf2e87 in QAction::activate (this=0x8c87d18, event=QAction::Trigger) at kernel/qaction.cpp:1160
#31 0xb6cf51ab in QAction::event (this=0x8c87d18, e=0xbfffaac4) at kernel/qaction.cpp:1079
#32 0xb756f069 in KAction::event (this=0x8c87d18, event=0xbfffaac4) at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kdeui/actions/kaction.cpp:88
#33 0xb6cf755c in QApplicationPrivate::notify_helper (this=0x80b75b0, receiver=0x8c87d18, e=0xbfffaac4) at kernel/qapplication.cpp:4057
#34 0xb6cff03e in QApplication::notify (this=0xbfffca18, receiver=0x8c87d18, e=0xbfffaac4) at kernel/qapplication.cpp:3604
#35 0xb7642cc3 in KApplication::notify (this=0xbfffca18, receiver=0x8c87d18, event=0xbfffaac4) at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kdeui/kernel/kapplication.cpp:302
#36 0xb8031b0b in QCoreApplication::notifyInternal (this=0xbfffca18, receiver=0x8c87d18, event=0xbfffaac4) at kernel/qcoreapplication.cpp:606
#37 0xb6d2b922 in QShortcutMap::dispatchEvent (this=0x80b7650, e=0xbfffae2c) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:213
#38 0xb6d2d60d in QShortcutMap::tryShortcutEvent (this=0x80b7650, o=0x8c6f350, e=0xbfffae2c) at kernel/qshortcutmap.cpp:369
#39 0xb6d003c3 in QApplication::notify (this=0xbfffca18, receiver=0x8c6f350, e=0xbfffae2c) at kernel/qapplication.cpp:3646
#40 0xb7642cc3 in KApplication::notify (this=0xbfffca18, receiver=0x8c6f350, event=0xbfffae2c) at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kdeui/kernel/kapplication.cpp:302
#41 0xb8031b0b in QCoreApplication::notifyInternal (this=0xbfffca18, receiver=0x8c6f350, event=0xbfffae2c) at kernel/qcoreapplication.cpp:606
#42 0xb6cf8a1e in qt_sendSpontaneousEvent (receiver=0x8c6f350, event=0x6) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:216
#43 0xb6d83bc3 in QKeyMapper::sendKeyEvent (keyWidget=0x8c6f350, grab=false, type=QEvent::KeyPress, code=86, modifiers={i = -1073762068}, text=@0xbfffb118, autorepeat=<value optimized out>, count=1, 
    nativeScanCode=55, nativeVirtualKey=118, nativeModifiers=4) at kernel/qkeymapper_x11.cpp:1675
#44 0xb6d85acb in QKeyMapperPrivate::translateKeyEvent (this=0x80dc3a0, keyWidget=0x8c6f350, event=0xbfffc62c, grab=false) at kernel/qkeymapper_x11.cpp:1645
#45 0xb6d5fd7c in QApplication::x11ProcessEvent (this=0xbfffca18, event=0xbfffc62c) at kernel/qapplication_x11.cpp:3459
#46 0xb6d872b2 in x11EventSourceDispatch (s=0x80ba390, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#47 0xb68b20c1 in IA__g_main_context_dispatch (context=0x80b9650) at gmain.c:2144
#48 0xb68b5753 in g_main_context_iterate (context=0x80b9650, block=1, dispatch=1, self=0x80b76f0) at gmain.c:2778
#49 0xb68b5911 in IA__g_main_context_iteration (context=0x80b9650, may_block=1) at gmain.c:2841
#50 0xb8059388 in QEventDispatcherGlib::processEvents (this=0x80b7590, flags={i = -1073756184}) at kernel/qeventdispatcher_glib.cpp:324
#51 0xb6d86aa5 in QGuiEventDispatcherGlib::processEvents (this=0x80b7590, flags={i = -1073756136}) at kernel/qguieventdispatcher_glib.cpp:202
#52 0xb80302aa in QEventLoop::processEvents (this=0xbfffc880, flags={i = -1073756072}) at kernel/qeventloop.cpp:149
#53 0xb803046a in QEventLoop::exec (this=0xbfffc880, flags={i = -1073756024}) at kernel/qeventloop.cpp:196
#54 0xb8032691 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:888
#55 0xb6cf73d7 in QApplication::exec () at kernel/qapplication.cpp:3526
#56 0xb7ef2a5d in kdemain (argc=3, argv=0x809ac38) at /var/tmp/portage/kde-base/kate-4.3.1/work/kate-4.3.1/kate/app/katemain.cpp:257
#57 0x0804e8e9 in launch (argc=3, _name=0x80959fc "kate", args=0x8095a10 "", cwd=0x0, envc=1, envs=0x8095a15 "DISPLAY=:0.0", reset_env=false, tty=0x0, avoid_loops=false, startup_id_str=0x8052374 "0")
    at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kinit/kinit.cpp:677
#58 0x0804ef7f in handle_launcher_request (sock=7, who=<value optimized out>) at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kinit/kinit.cpp:1169
#59 0x0804f62f in handle_requests (waitForPid=0) at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kinit/kinit.cpp:1362
#60 0x0804fbd4 in main (argc=2, argv=0xbfffd474, envp=0xbfffd480) at /var/tmp/portage/kde-base/kdelibs-4.3.1/work/kdelibs-4.3.1/kinit/kinit.cpp:1793

Reported using DrKonqi