Re: segfaults building documentation when machine under load

[Andreas Weber]

Am 19.05.20 um 11:04 schrieb Andreas Weber:
> I can reproduce this with any "txt" output using GNU parallel, for
> example (from the build directory):
> 
> parallel -N0 -q ./run-octave --norc --silent --no-history --path
> ../octave-src/doc/interpreter/ --eval "plotimages ('doc/interpreter/',
> 'hist', 'txt');" ::: {1..50}
> 
> This generates segfaults with plotimages, sparseimages, splineimages and
> so on...

I'm not able to reproduce it with debugging symbols... but here is gdb
without without symbols:

Thread 1 "octave-gui" received signal SIGSEGV, Segmentation fault.
0x00007ffff3ccb592 in QMetaObject::invokeMethod(QObject*, char const*,
Qt::ConnectionType, QGenericReturnArgument, QGenericArgument,
QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument,
QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument,
QGenericArgument) ()
   from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5

(gdb) bt
#0  0x00007ffff3ccb592 in QMetaObject::invokeMethod(QObject*, char
const*, Qt::ConnectionType, QGenericReturnArgument, QGenericArgument,
QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument,
QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument,
QGenericArgument) ()
    at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#1  0x00007ffff7d59320 in QMetaObject::invokeMethod(QObject*, char
const*, Qt::ConnectionType, QGenericArgument, QGenericArgument,
QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument,
QGenericArgument, QGenericArgument, QGenericArgument, QGenericArgument)
    (val9=..., val8=..., val7=..., val6=..., val5=..., val4=...,
val3=..., val2=..., val1=..., val0=..., type=<optimized out>,
member=0x7ffff7e55d8b "slotFinalize", obj=<optimized out>) at
/usr/include/x86_64-linux-gnu/qt5/QtCore/qobjectdefs.h:444
#2  0x00007ffff7d59320 in QtHandles::ObjectProxy::finalize()
(this=0x7fffbc4acaf0) at ../octave-src/libgui/graphics/ObjectProxy.cc:110
#3  0x00007ffff7d59320 in QtHandles::ObjectProxy::finalize()
(this=0x7fffbc4acaf0) at ../octave-src/libgui/graphics/ObjectProxy.cc:100
#4  0x00007ffff7d59351 in
QtHandles::ObjectProxy::setObject(QtHandles::Object*)
(this=this@entry=0x7fffbc4acaf0, obj=obj@entry=0x5555557e48b0)
    at ../octave-src/libgui/graphics/ObjectProxy.cc:86
#5  0x00007ffff7d8a795 in
QtHandles::qt_graphics_toolkit::create_object(double)
(this=0x7fffbc16b850, handle=-31.839112234376785)
    at ../octave-src/libgui/graphics/qt-graphics-toolkit.cc:452
#6  0x00007ffff3ce5072 in QObject::event(QEvent*) () at
/usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007ffff46384c1 in QApplicationPrivate::notify_helper(QObject*,
QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#8  0x00007ffff463f970 in QApplication::notify(QObject*, QEvent*) () at
/usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#9  0x00007ffff7de0723 in octave::octave_qapplication::notify(QObject*,
QEvent*) (this=0x5555556434a0, receiver=<optimized out>, ev=<optimized out>)
    at ../octave-src/libgui/src/octave-qobject.cc:132
#10 0x00007ffff3cbb489 in QCoreApplication::notifyInternal2(QObject*,
QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#11 0x00007ffff3cbe46b in
QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*)
() at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#12 0x00007ffff3d0d103 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#13 0x00007ffff10ddf2e in g_main_context_dispatch () at
/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#14 0x00007ffff10de1c8 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#15 0x00007ffff10de25c in g_main_context_iteration () at
/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#16 0x00007ffff3d0c727 in
QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>)
() at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#17 0x00007fffcedc4401 in  () at /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#18 0x00007ffff3cba15b in
QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at
/usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#19 0x00007ffff3cc2132 in QCoreApplication::exec() () at
/usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#20 0x00007ffff7dea17d in octave::qt_application::execute()
(this=this@entry=0x7fffffffc4c0) at
../octave-src/libgui/src/qt-application.cc:73
#21 0x0000555555555396 in main(int, char**) (argc=15,
argv=0x7fffffffc7d8) at ../octave-src/src/main-gui.cc:106