Emacs crash with gtk3, not with gtk2, related to X_SetInputFocus

[asjo koldfront dk (Adam Sjøgren)]

  Hi.

I recently reported an Emacs crash to the emacs developers, which
happens when Emacs is compiled with gtk3, but not with gtk2.

When I iconify the Emacs window and then move the mouse over the icon, I
get the crash, with an error like this: "X protocol error: BadMatch
(invalid parameter attributes) on protocol request 42", which seems to
be X_SetInputFocus() related¹.

Details:

 * http://article.gmane.org/gmane.emacs.devel/144994

I am trying to figure out whether it is an Emacs issue, a gtk3 issue, or
perhaps something else (like the window manager I use, fvwm).

Do you know if handling of focus, of iconified windows or otherwise, has
changed dramatically in gtk3?

I may very well be barking up the wrong tree, so any suggestions on how
to get to the bottom of this are very welcome.

This is compiling the latest Emacs trunk code on a Debian unstable amd64
system with libgtk-3-0 3.0.12-2 and fvwm 1:2.5.30.ds-1 installed.

  Best regards,

     Adam

¹ http://web.archiveorange.com/archive/v/Ky751WDYQzZS9uVf9WRU

-- 
 "Gav                                                         Adam Sjøgren
  Strik"                                                 asjo koldfront dk