Stucked with a bug fixing.

[Eduardo]

I am trying to find what is the cause of bug #41896  but I am lost at some point. I have been debugging with gdb and I found where the UI freezes. I am reproducing the case when the pager is active and I try to close the main window. After the QCloseEvent is handled that is what happens:

in main-window.cc:

void
main_window::closeEvent (QCloseEvent *e)
{
  e->ignore ();
  octave_link::post_event (this, &main_window::exit_callback);
}

After this function exits normally, I do some steps with gdb and that is what I obtain from it:

main_window::closeEvent (this=0x7fffe8a8fcc0, e=0x7fffe8a8f260) at ../../libgui/src/main-window.cc:894
894    }
(gdb)
0x00007fa936edec02 in QWidget::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
(gdb)
Single stepping until exit from function _ZN7QWidget5eventEP6QEvent,
which has no line number information.
0x00007fa9372a71cb in QMainWindow::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
(gdb)
Single stepping until exit from function _ZN11QMainWindow5eventEP6QEvent,
which has no line number information.
0x00007fa936e8ee9c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
(gdb)
Single stepping until exit from function _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent,
which has no line number information.
0x00007fa936e9330a in QApplication::notify(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
(gdb)
Single stepping until exit from function _ZN12QApplication6notifyEP7QObjectP6QEvent,
which has no line number information.
0x00007fa93696a56e in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
(gdb)
Single stepping until exit from function _ZN16QCoreApplication14notifyInternalEP7QObjectP6QEvent,
which has no line number information.
0x00007fa936ed86b1 in QWidgetPrivate::close_helper(QWidgetPrivate::CloseMode) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
(gdb)
Single stepping until exit from function _ZN14QWidgetPrivate12close_helperENS_9CloseModeE,
which has no line number information.
0x00007fa936f0e00f in QApplication::x11ClientMessage(QWidget*, _XEvent*, bool) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
(gdb)
Single stepping until exit from function _ZN12QApplication16x11ClientMessageEP7QWidgetP7_XEventb,
which has no line number information.
0x00007fa936f0c46c in QApplication::x11ProcessEvent(_XEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
(gdb)
Single stepping until exit from function _ZN12QApplication15x11ProcessEventEP7_XEvent,
which has no line number information.
0x00007fa9301dcab5 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
(gdb)
Single stepping until exit from function g_main_context_dispatch,
which has no line number information.
0x00007fa9301dcea4 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
(gdb)
Single stepping until exit from function g_main_context_iteration,
which has no line number information.
0x00007fa936998c16 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
(gdb)
Single stepping until exit from function _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE,
which has no line number information.
0x00007fa9369692bf in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
(gdb)
Single stepping until exit from function _ZN10QEventLoop13processEventsE6QFlagsINS_17ProcessEventsFlagEE,
which has no line number information.
0x00007fa936969548 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
(gdb)
Single stepping until exit from function _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE,
which has no line number information.

**At that point it just freezes and the only way to continue is to get out of the less pager. Then it continues like normally.


0x00007fa93696e708 in QCoreApplication::exec() () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
(gdb)
Single stepping until exit from function _ZN16QCoreApplication4execEv,
which has no line number information.
main_window::~main_window (this=0x7fffe8a8fcc0, __in_chrg=<optimized out>) at ../../libgui/src/main-window.cc:127
127    main_window::~main_window (void)

(....)

I am totally lost at this point, and don't know why QCoreApplication::exec() blocks all. Anyone have an Idea of what is maybe happening here?

Eduardo