Zeljan,

I finally got a proper backtrace for the SIGSEGV that shows up only in my AMD 64-bit 3-core "super-computer".
It happens sometimes, maybe once in few hours, and only when moving mouse on the source editor.

Linux Mint 13 + KDE 4.8.

Regards,
Juha

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Program received signal SIGSEGV, Segmentation fault. 0x00000000005d623c in fpc_check_object ()
(gdb) bt
#0 0x00000000005d623c in fpc_check_object ()
#1 0x00007fffffffcea0 in ?? ()
#2 0x0000000000962e86 in SLOTMOUSEMOVE (this=0x7fffd2808650, SENDER=0x28731b0, EVENT=0x7fffffffd690) at qt/qtwidgets.pas:3492 #3 0x000000000095f970 in EVENTFILTER (this=0x7fffd2808650, SENDER=0x28731b0, EVENT=0x7fffffffd690) at qt/qtwidgets.pas:2384 #4 0x00000000009847d2 in EVENTFILTER (this=0x7fffd2808650, SENDER=0x28731b0, EVENT=0x7fffffffd690) at qt/qtwidgets.pas:14310 #5 0x0000000000986017 in VIEWPORTEVENTFILTER (this=0x7fffd0613550, EVENT=0x7fffffffd690, RETVAL=0x7fffffffd0df) at qt/qtwidgets.pas:14782 #6 0x00007ffff7727b7d in
QLCLAbstractScrollArea::viewportEvent(QEvent*) () from /usr/local/lib/libQt4Pas.so.5
#7 0x00007ffff3d76028 in
QCoreApplicationPrivate::sendThroughObjectEventFilters(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4 #8 0x00007ffff45e485f in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4 #9 0x00007ffff45ea0bf in QApplication::notify(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#10 0x00007ffff3d75e9c in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4 #11 0x00007ffff45e5862 in
QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#12 0x00007ffff4664bf5 in ?? () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4 #13 0x00007ffff4663bae in QApplication::x11ProcessEvent(_XEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#14 0x00007ffff468d0d2 in ?? () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4 #15 0x00007ffff1a8cd53 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#16 0x00007ffff1a8d0a0 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0 #17 0x00007ffff1a8d164 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#18 0x00007ffff3da53bf in
QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#19 0x00007ffff468cd5e in ?? () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4 #20 0x00007ffff3d7a10f in
QCoreApplication::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#21 0x00007ffff76a629f in QCoreApplication_processEvents () from /usr/local/lib/libQt4Pas.so.5
#22 0x000000000082f056 in APPPROCESSMESSAGES (this=0x7ffff7f7df50) at qt/qtobject.inc:281
#23 0x0000000000637fc6 in HANDLEMESSAGE (this=0x7ffff7f7c350) at include/application.inc:1280
#24 0x000000000063872d in RUNLOOP (this=0x7ffff7f7c350) at include/application.inc:1413
#25 0x000000000082f026 in APPRUN (this=0x7ffff7f7df50, ALOOP=...) at qt/qtobject.inc:252
#26 0x00000000006386b1 in RUN (this=0x7ffff7f7c350) at include/application.inc:1401
#27 0x00000000005d4093 in main () at lazarus.pp:115

FPC version is 2.6.0

hm...I don't see anything strange with that trace. LCLObject is still valid and according to your strace it dies in DeliverMessage() for some reason (as you said you're only moving mouse over source editor, so no way that LCLObject is dead).

zeljko

Maybe it's range error in TQtWidgetSet.SlotMouse() ?? That cast to SmallInt is probably same problem like Martin & Mattias had with carbon in Eindhoven.

z