bug#1179: Emacs on Windows hangs displaying unibyte strings

[Eli Zaretskii <eliz@gnu.org>]

> Date: Fri, 17 Oct 2008 15:32:47 +0200
> From: "Juanma Barranquero" <lekktu@gmail.com>
> Cc: 1179 <1179@emacsbugs.donarmstrong.com>
> 
> On Fri, Oct 17, 2008 at 15:01, Eli Zaretskii <eliz@gnu.org> wrote:
> 
> > It doesn't crash for me, with today's CVS.  But the result is strange
> > nonetheless, I think: the single á character in the last line above
> > are replaced with _two_ empty boxes about which "C-u C-x =" says:
> 
> Could you please try with DejaVu Sans Mono?

Tried it, the results are identical to what I reported for the default
font.  Btw, I selected DejaVu Sans Mono via S-mouse-1, in case it
matters.

> I see these four different outputs:
> 
>  - Non-optimized build, Courier New: same as you.
>  - Non-optimized build, DejaVu Sans Mono: the á character is replaced
> by two spaces (not empty boxes) and Emacs hangs.
>  - Optimized build, Courier New: á is replaced by two empty boxes, Emacs hangs.
>  - Optimized build, DejaVu Sans Mono: Emacs crashes at w32term.c:1279.

I use an older GCC (3.4.2), perhaps that's the reason for the
difference.

> (gdb) disassemble 0x011f804c
> Dump of assembler code for function x_draw_glyph_string_background:
> [...]
> 0x011f804c <x_draw_glyph_string_background+48>: cmp    %esi,0x58(%eax)

What's the value of the EAX register ("p/x $eax") at this point?