bug#11080: 24.0.94; Assertion failure in signal handler

[Eli Zaretskii]

> From: Johan Bockgård <bojohan@gnu.org>
> Date: Sat, 24 Mar 2012 00:24:22 +0100
> 
> 
> emacs -Q
> 
> ;; "foo" is any non-existing or non-xbm file.
> ;; Eval:
> (face-remap-add-relative 'default '(:stipple "foo"))
> 
> C-h k x
> 
> Move the mouse pointer over one of the links in the lower window.
> 
>    =>
> 
> eval.c:3403: Emacs fatal error: assertion failed: !handling_signal

Please show the full backtrace, all the way up to the `main' function,
and also the Lisp backtrace.  It is important to see all that to
understand how come this code was called with handling_signal
non-zero.  Thanks.