bug#16049: 24.3.50; Crash on startup on Mac OS X 10.9

[Eli Zaretskii]

> From: Jan Djärv <jan.h.d@swipnet.se>
> Date: Thu, 5 Dec 2013 20:59:00 +0100
> Cc: martin rudalics <rudalics@gmx.at>,
>  Jules Colding <colding@venalicium.dk>,
>  16049@debbugs.gnu.org
> 
> (gdb) p desired_matrix->nrows
> $1 = -306783372
> 
> This is not random, I get the same value each time.  Overflow?

Put a watchpoint on that address, and see who gives it such a bogus
value.