bug#17499: current dfa.c can malloc 0 bytes

[Paul Eggert]

On 05/15/2014 09:22 AM, Aharon Robbins wrote:
> It seems that code in the grep master dfa.c can call xmalloc with
> an amount that is zero.  This is OK on GLIBC but is causing some failures
> on other systems where malloc(0) fails.

Thanks, I'll try to take a look at this from your recipe.  Are there any 
more details about the failure? What are the symptoms?

A quick look at the dfa.c source code in grep suggests that it can't be 
a direct call to xmalloc, as those args all must be nonzero.  Perhaps 
it's indirect, via xnmalloc or something like that?

Also, gnulib's xmalloc doesn't mind if malloc (0) returns NULL. Is 
gawk's xmalloc pickier?  If so, why?