bug#18997: 24.4; IDLWAVE: Emacs crashes when trying to change the window while in the IDL shell

[Eli Zaretskii <eliz@gnu.org>]

> Date: Fri, 13 Nov 2015 08:52:29 -0800
> From: Gordon Farquharson <gordonfarquharson@gmail.com>
> Cc: Glenn Morris <rgm@gnu.org>, 18997@debbugs.gnu.org
> 
>     See gud-tool-bar-map and its uses. As you see, GUD uses a very
>     different method.
> 
> I'll take a look. I've never programmed in elisp. The closest related language
> I've used is scheme, a very long time ago, so this will be exciting.

I think on the Lisp level everything is OK.  Fact is, this worked
before the changes in GTK toolbar support mentioned previously in
discussing this thread.  It also works with other toolkits (Glenn
mentioned Lucid, I see it display correctly on MS-Windows).

So I think a better strategy would be to step in a debugger through
the offending C code and see the differences between when IDLWAVE is
invoked, and when GUD is invoked.  You can identify the code that's
involved in this by examining the series of functions that crash.
Based on the Glib error messages posted up-thread, I would suggest to
start in xg_get_pixbuf_from_pixmap, which calls
gdk_pixbuf_new_from_data, the first function to complain.  How is the
data there different between GUD and IDLWAVE?