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

[Eli Zaretskii]

> Date: Mon, 29 Oct 2012 10:56:48 -0700
> From: Ami Fischman <ami@fischman.org>
> Cc: 12745@debbugs.gnu.org
> 
> In case it's useful, replacing
> printf "%s: %d glyphs\n", ($area == 0 ? "LEFT" : $area == 2 ? "RIGHT" :
> "TEXT"), $used
> in pgrowx with:
> printf "%d glyphs\n", $used
> gives me:

Yes, it's useful, thanks.

>  19  138: CHAR[,] pos=1294 blev=0,btyp=L w=6 a+d=10+2 MB
>  20  144: CHAR[ ] str=61334f1[0] blev=0,btyp=L w=6 a+d=10+2 MB
>  21  150: STRETCH[12+10] str=61335d1[1] w=354 a+d=10+2 MB
>  22  504: IMAGE[0] str=61335d1[2] w=6 a+d=10+2 MB slice=0,0,6,12
> 
> (I imagine the IMAGE at the end there is
> fci-mode<https://github.com/alpaker/Fill-Column-Indicator>
> )

Yes, and so is the STRETCH glyph.  Can you figure out what is the
string before that, viz.:

>  20  144: CHAR[ ] str=61334f1[0] blev=0,btyp=L w=6 a+d=10+2 MB

This is a display string or an overlay string, but where does it come
from, and which mode puts it there?