bug#9087: Crash reading from minibuffer with icomplete-mode

[Eli Zaretskii]

> From: Juanma Barranquero <lekktu@gmail.com>
> Date: Fri, 15 Jul 2011 18:39:57 +0200
> Cc: 9087@debbugs.gnu.org
> 
> Hardware watchpoint 3: interrupt_input_blocked
> 
> Old value = 0
> New value = 1
> xmalloc (size=16) at alloc.c:673
> 673       val = (POINTER_TYPE *) malloc (size);
> $1 = 1
> #0  xmalloc (size=16) at alloc.c:673
> #1  0x0100280a in sort_args (argc=4, argv=0x9e2d70) at emacs.c:1831
> 
> Lisp Backtrace:
> Cannot access memory at address 0x730077
> (gdb)
> 
> and so it does not continue.

src/.gdbinit defines a hookpost-backtrace command that invokes
xbacktrace, which fails here.  To avoid the above, either redefine
hookpost-backtrace to an empty command (after starting GDB), or start
GDB from a directory other than Emacs's src/, so .gdbinit isn't read.
(You can always read it later, with the `source' command, if needed.)