bug#12745: crash in bidi_pop_it during (idle) redisplay

[Eli Zaretskii]

> Date: Mon, 29 Oct 2012 11:29:28 -0700
> From: Ami Fischman <ami@fischman.org>
> Cc: 12745@debbugs.gnu.org
> 
> I'm groping in the dark, but AFAICT it's a null str?

No, it looks like a string with a blank character.

> (gdb) p/x (it->glyph_row->glyphs[1][20].object)
> $39 = 0x61334f1
> (gdb) p *(it->glyph_row->glyphs[1][20].object)
> $40 = 0

To be sure, try this:

  (gdb) p it->glyph_row->glyphs[1][20].object
  (gdb) xtype

If I'm right, it should tell that the object is a Lisp string, and you
can then display it like you did with the name of the buffer.

> The only guess I have is that I had entered a trailing space after that
> comma, which would highlight it as trailing whitespace because of this
> snippet from my .emacs:
> (highlight-regexp "[ \t]+$" 'hi-blue)
> using hi-lock-mode.

Probably.  But then why isn't there a "face=" part there?  hi-blue is
not the default face, is it?