bug#18438: 24.4.50; assertion failed in bidi.c

[Eli Zaretskii]

> Date: Tue, 16 Sep 2014 14:59:32 +1200
> From: aidalgol@amuri.net
> Cc: Eli Zaretskii <eliz@gnu.org>
> 
> > The only reason I could think of for such assertion violations is
> > some asynchronously run code that doesn't properly restore
> > registers.  Which is pretty far-fetched, but what else can explain
> > this?
> 
> I still have this session open, by the way.  Do you want anything more 
> out of it?

If you don't mind messing with assembler, it would be interesting to
disassemble bidi_check_type, see in which register it holds the value
when it tests it, and then look at the actual value in that register
in the bidi_check_type's call-stack frame.

TIA