bug#14264: 24.3.50; SEGV in char_table_ref's use of SUB_CHAR_TABLE_P

[Eli Zaretskii]

> From: Glenn Morris <rgm@gnu.org>
> Cc: jim@meyering.net,  14264@debbugs.gnu.org
> Date: Wed, 23 Oct 2013 03:53:20 -0400
> 
> Eli Zaretskii wrote:
> 
> > Sorry, still no cigar.
> 
> Any other info I can usefully provide?

Well, it would be useful to find out how come Emacs comes with such a
bogus character code in the middle of what is supposed to be pure
ASCII text.  Can you set a breakpoint in scan_for_column, just before
it calls composition_compute_stop_pos, conditioned on scan = 1645,
then step inside composition_compute_stop_pos, and see how come it
fetches such a character code?  Is buffer text being corrupted by
something?

TIA