bug#21428: 24.5; Crash of emacs on OS X, installed via homebrew cask

[Eli Zaretskii <eliz@gnu.org>]

> From: Rainer M Krug <Rainer@krugs.de>
> Cc: 21428@debbugs.gnu.org,  mituharu+bug-gnu-emacs-mac@math.s.chiba-u.ac.jp
> Date: Fri, 25 Sep 2015 11:34:03 +0200
> 
> OK - new crash: I updated this morning from git and recompiled.
> 
> This time it is face #42 and it seems to be in the bar above the
> minibuffer (mode-line)??? The character look like mode-bar, but I can't
> see them anywhere.

It's not a mode line: the characters come from a buffer, whereas they
come from strings.  Also, the number of characters is too small for a
mode line, and the beginning doesn't resemble a mode line.

The "vpos=1" part here:

> | #7  0x000000010000f902 in update_window_line (w=0x1020bfbe0, vpos=1, mouse_face_overwritten_p=0x7fff5fbfbdc2) at dispnew.c:3854

means this is the second (zero-based) screen line of some window.  It
looks like a mode spec at the beginning of some Org file:

  #     -*- mode: org -*-

Does that ring any bells?  Can you try recreating that window in a
live session, so we could see what face is #42?

> | (gdb) p f->face_cache->used
> | $1 = 31

Hmmm, the same number 31 as in the previous crash.  Interesting.

Thanks.