Version:            (using Devel)
Installed from:    Compiled sources
Compiler:          gcc version 4.1.2 20070214 
OS:                Linux

Today I ran a gdb backtrace of a crash and compiled the boost libraries when KWin all of a sudden crashed. It might have been due to the fact that my computer may have ran out of RAM / Swapspace and that that somehow triggered the crash. The problem is that I did not exactly monitor how much swapspace was used or still available, so that I cannot confirm this theory. However, I do know that my computer made heavy use of the swapspace before the crash. Regrettably, I cannot reproduce the crash. 

The backtrace was:
Application: KWin (kwin), signal SIGSEGV
Using host libthread_db library "/lib/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread 0xb6896900 (LWP 10535)]
[New Thread 0xb52e2b90 (LWP 12843)]
[KCrash handler]
#6  0xb7ac1db1 in QMetaObject::activate (sender=0x819ab80, m=0xb7b5f258, 
    local_signal_index=4, argv=0xbfdccc5c) at kernel/qobject.cpp:3136
#7  0xb7a4e154 in QProcess::stateChanged (this=0x819ab80, 
    _t1=QProcess::NotRunning) at .moc/debug-shared/moc_qprocess.cpp:147
#8  0xb7a4fd35 in QProcessPrivate::_q_processDied (this=0x81d2a98)
    at io/qprocess.cpp:669
#9  0xb7a917bd in QProcessPrivate::waitForFinished (this=0x81d2a98, 
    msecs=30000) at io/qprocess_unix.cpp:1153
#10 0xb7a4eb2c in QProcess::waitForFinished (this=0x819ab80, msecs=30000)
    at io/qprocess.cpp:1290
#11 0xb7a4ec4c in ~QProcess (this=0x819ab80) at io/qprocess.cpp:752
#12 0xb7f42391 in KWin::Client::gotPing (this=0x825ed88, timestamp=3429999349)
    at /var/tmp/portage/kde-base/kdebase-9999.4/work/kdebase-9999.4/workspace/kwin/client.cpp:1084
#13 0xb7f6088e in KWin::RootInfo::gotPing (this=0x812c798, w=52428801, 
    timestamp=3429999349)
    at /var/tmp/portage/kde-base/kdebase-9999.4/work/kdebase-9999.4/workspace/kwin/events.cpp:204
#14 0xb6f10670 in NETRootInfo::event (this=0x812c798, event=0xbfdcd398, 
    properties=0xbfdccfe8, properties_size=5)
    at /var/tmp/portage/kde-base/kdelibs-9999.4/work/kdelibs-9999.4/kdeui/windowmanagement/netwm.cpp:1949
#15 0xb7f5feea in KWin::Workspace::workspaceEvent (this=0x80edb80, 
    e=0xbfdcd398)
    at /var/tmp/portage/kde-base/kdebase-9999.4/work/kdebase-9999.4/workspace/kwin/events.cpp:233
#16 0xb7f509b4 in KWin::Application::x11EventFilter (this=0xbfdcd5d4, 
    e=0xbfdcd398)
    at /var/tmp/portage/kde-base/kdebase-9999.4/work/kdebase-9999.4/workspace/kwin/main.cpp:278
#17 0xb7136a2e in qt_x11EventFilter (ev=0xbfdcd398)
    at kernel/qapplication_x11.cpp:341
#18 0xb7143a67 in QApplication::x11ProcessEvent (this=0xbfdcd5d4, 
    event=0xbfdcd398) at kernel/qapplication_x11.cpp:2793
#19 0xb7169c45 in QEventDispatcherX11::processEvents (this=0x8054468, 
    flags=@0xbfdcd484) at kernel/qeventdispatcher_x11.cpp:125
#20 0xb7aad191 in QEventLoop::processEvents (this=0xbfdcd4f0, 
    flags=@0xbfdcd4b8) at kernel/qeventloop.cpp:140
#21 0xb7aad29a in QEventLoop::exec (this=0xbfdcd4f0, flags=@0xbfdcd4f8)
    at kernel/qeventloop.cpp:186
#22 0xb7aaf626 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:759
#23 0xb70df487 in QApplication::exec () at kernel/qapplication.cpp:3053
#24 0xb7f52104 in kdemain (argc=3, argv=0xbfdcd7a4)
    at /var/tmp/portage/kde-base/kdebase-9999.4/work/kdebase-9999.4/workspace/kwin/main.cpp:427
#25 0x080487b2 in main (argc=)
    at /var/tmp/portage/kde-base/kdebase-9999.4/work/kdebase_build/workspace/kwin/kwin_dummy.cpp:3
#26 0xb69b5fdc in __libc_start_main (main=0x8048790 <main>, argc=3, 
    ubp_av=0xbfdcd7a4, init=0x80487e0 <__libc_csu_init>, 
    fini=0x80487d0 <__libc_csu_fini>, rtld_fini=0xb7fc3100 <_dl_fini>, 
    stack_end=0xbfdcd79c) at libc-start.c:229
#27 0x08048701 in _start ()
#0  0xffffe410 in __kernel_vsyscall ()