Re: Gtk::Widget::on_hide

[John Emmas <johne53 tiscali co uk>]

On 21/11/2013 09:17, Kjell Ahlstedt wrote:
> Getting back to 
> https://mail.gnome.org/archives/gtkmm-list/2013-November/msg00043.html, you 
> say there, before you applied any patches, that gobject_ is set to 0 
> in Gtk::Object::disconnect_cpp_wrapper(), and then 
> Gtk::Widget::on_unrealize() is called, and the program crashes there, 
> because gobject_ == 0. But when disconnect_cpp_wrapper() sets gobject_ 
> = 0, it also removes Glib::quark_ with 
> g_object_steal_qdata((GObject*)gobj(), Glib::quark_). If that's done, 
> on_unrealize() won't be called. See also 
> https://mail.gnome.org/archives/gtkmm-list/2013-November/msg00045.html.

Thanks Kjell, I now understand what you meant when you said that 
'steal_qdata' and 'set_qdata' weren't doing what they're supposed to 
do.  It's academic now of course - but before I applied the patch, you 
must have been right with that assertion.


> The most puzzling thing is why you are (as far as I know) the only one 
> who have reported crashes with even the shortest possible gtkmm 
> applications. Your problems are so severe that I would expect 
> complaints from most affected users of gtkmm.

The only explanation I can think of is that something changed very very 
recently so most users haven't had time to encounter it yet. The main 
point is that it does seem likely that those patches are needed in 2.24.4.

As it happens I did encounter one snag while applying the patches but 
rather than describe it here I'll update the bug report later, so it's 
in the right place.  Thanks for all the effort you've put into 
investigating this problem.

John