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

[Eli Zaretskii]

> Date: Fri, 24 Oct 2014 10:54:50 +1300
> From: aidalgol@amuri.net
> Cc: Ken Brown <kbrown@cornell.edu>, Eli Zaretskii <eliz@gnu.org>
> 
> Welp, another one bites the dust.  Asserts still happening.

Did you make sure this is a bogus assertion violation?  In this case:

> #0  terminate_due_to_signal (sig=6, backtrace_limit=2147483647) at emacs.c:351
> No locals.
> #1  0x00000001005b0395 in die (msg=0x100a44842 <DEFAULT_REHASH_SIZE+506> 
> "CONSP (tail)", file=0x100a44650 <DEFAULT_REHASH_SIZE+8> "intervals.c", 
> line=1777) at alloc.c:6833
> No locals.
> #2  0x000000010064151a in lookup_char_property (plist=25793766198, 
> prop=4306944674, textprop=true) at intervals.c:1777
>         tail = 4306571314
>         fallback = 4306571314

On line 1777 of intervals.c, do the following commands

 (gdb) frame 2
 (gdb) p tail
 (gdb) xtype

say that 'tail' is a Lisp_Cons?  If so, then the assertion violation
is indeed bogus.