Hello, you have infinity loop here:
#0  0x000000000048ae5d in findNode (akey=@0x7fff37bab1b8: -1, this=0x1df04c0) at /usr/include/qt4/QtCore/qmap.h:487
#1  find (akey=@0x7fff37bab1b8: -1, this=0x1df04c0) at /usr/include/qt4/QtCore/qmap.h:621
#2  AlarmCalendar::removeKAEvents (this=0x1df04a0, key=-1, closing=true, types=...) at /var/tmp-disk/portage/kde-base/kalarm-4.9.5/work/kalarm-4.9.5/kalarm/alarmcalendar.cpp:659
#3  0x000000000048b5b6 in AlarmCalendar::close (this=0x1df04a0) at /var/tmp-disk/portage/kde-base/kalarm-4.9.5/work/kalarm-4.9.5/kalarm/alarmcalendar.cpp:522
#4  0x000000000048b7a3 in AlarmCalendar::~AlarmCalendar (this=0x1df04a0, __in_chrg=<optimized out>) at /var/tmp-disk/portage/kde-base/kalarm-4.9.5/work/kalarm-4.9.5/kalarm/alarmcalendar.cpp:226
#5  0x000000000048b929 in AlarmCalendar::~AlarmCalendar (this=0x1df04a0, __in_chrg=<optimized out>) at /var/tmp-disk/portage/kde-base/kalarm-4.9.5/work/kalarm-4.9.5/kalarm/alarmcalendar.cpp:227
#6  0x0000000000488103 in AlarmCalendar::terminateCalendars () at /var/tmp-disk/portage/kde-base/kalarm-4.9.5/work/kalarm-4.9.5/kalarm/alarmcalendar.cpp:120
#7  0x00000000004a37c9 in KAlarmApp::quitIf (this=0x1b94ce0, exitCode=0, force=<optimized out>) at /var/tmp-disk/portage/kde-base/kalarm-4.9.5/work/kalarm-4.9.5/kalarm/kalarmapp.cpp:587
#8  0x00000000004a865c in KAlarmApp::restoreSession (this=0x1b94ce0) at /var/tmp-disk/portage/kde-base/kalarm-4.9.5/work/kalarm-4.9.5/kalarm/kalarmapp.cpp:287
#9  0x0000000000451362 in main (argc=3, argv=0x7fff37bac378) at /var/tmp-disk/portage/kde-base/kalarm-4.9.5/work/kalarm-4.9.5/kalarm/main.cpp:129
(gdb) bt full
#0  0x000000000048ae5d in findNode (akey=@0x7fff37bab1b8: -1, this=0x1df04c0) at /usr/include/qt4/QtCore/qmap.h:487
        i = 0
        cur = 0x1d35440
        next = 0x1d16010
#1  find (akey=@0x7fff37bab1b8: -1, this=0x1df04c0) at /usr/include/qt4/QtCore/qmap.h:621
No locals.
#2  AlarmCalendar::removeKAEvents (this=0x1df04a0, key=-1, closing=true, types=...) at /var/tmp-disk/portage/kde-base/kalarm-4.9.5/work/kalarm-4.9.5/kalarm/alarmcalendar.cpp:659
        removed = false
#3  0x000000000048b5b6 in AlarmCalendar::close (this=0x1df04a0) at /var/tmp-disk/portage/kde-base/kalarm-4.9.5/work/kalarm-4.9.5/kalarm/alarmcalendar.cpp:522
No locals.
#4  0x000000000048b7a3 in AlarmCalendar::~AlarmCalendar (this=0x1df04a0, __in_chrg=<optimized out>) at /var/tmp-disk/portage/kde-base/kalarm-4.9.5/work/kalarm-4.9.5/kalarm/alarmcalendar.cpp:226
No locals.
#5  0x000000000048b929 in AlarmCalendar::~AlarmCalendar (this=0x1df04a0, __in_chrg=<optimized out>) at /var/tmp-disk/portage/kde-base/kalarm-4.9.5/work/kalarm-4.9.5/kalarm/alarmcalendar.cpp:227
No locals.
#6  0x0000000000488103 in AlarmCalendar::terminateCalendars () at /var/tmp-disk/portage/kde-base/kalarm-4.9.5/work/kalarm-4.9.5/kalarm/alarmcalendar.cpp:120
No locals.
#7  0x00000000004a37c9 in KAlarmApp::quitIf (this=0x1b94ce0, exitCode=0, force=<optimized out>) at /var/tmp-disk/portage/kde-base/kalarm-4.9.5/work/kalarm-4.9.5/kalarm/kalarmapp.cpp:587
        __PRETTY_FUNCTION__ = "bool KAlarmApp::quitIf(int, bool)"
#8  0x00000000004a865c in KAlarmApp::restoreSession (this=0x1b94ce0) at /var/tmp-disk/portage/kde-base/kalarm-4.9.5/work/kalarm-4.9.5/kalarm/kalarmapp.cpp:287
        __PRETTY_FUNCTION__ = "bool KAlarmApp::restoreSession()"
        trayParent = 0x0
#9  0x0000000000451362 in main (argc=3, argv=0x7fff37bac378) at /var/tmp-disk/portage/kde-base/kalarm-4.9.5/work/kalarm-4.9.5/kalarm/main.cpp:129
        aboutData = {d = 0x1b49b90}
        options = {d = 0x1b582f0}
        __PRETTY_FUNCTION__ = "int main(int, char**)"
        app = <optimized out>

Cheer,

Reproducible: Sometimes