[ruby-gnome2-devel-en] Crashes when cairo is compiled with xlib-xcb xcb options

[Stefan S. <ma...@ss...>]

Dear Mr Kouhei Sutou,

have you ever tested rcairo for cairo library compiled with xlib-xcb xcb
support?

cairo-1.14.6 was compiled with that options on my Gentoo AMD64 Linux
box, and I discovered yesterday that my program 
http://ssalewski.de/PetEd.html.en crashed when I started it with command
"ruby peted.rb" and immediately closed that empty window by clicking the
cross on top right corner.

That is for ruby-gnome2-3.0.7, ruby 2.2 and GTK 3.16.

I had no idea about the crash (segmentation fault). I tested cairo
-pong.rb, that works fine. Now I recompiled cairo without xlib-xcb xcb
options, and crash is gone.

That is not a big problem for me currently, my program is still
unfinished and I can use cairo without lib-xcb xcb.

Later, if other people may use my program with lib-xcb xcb enabled it
may be a problem.

Of course my program may have a serious bug. But I wonder why the crash
occurs only with cairo options lib-xcb xcb. And just clicking the cross
on top right corner direct after startup is a simple operation, there is
no code which is executed in my program. I have noticed that I can avoid
the crash when I start it with a file argument like "ruby peted.rb
test.sch" and move some symbols around before terminating the program.
And generally the program seems to work the same with and without cairo
options lib-xcb xcb. Problem is only termination, but debugging that is
really difficult.

Best regards,

Stefan Salewski