[PATCH] Don't pass NULL pointer to error [BZ #24556]

[Paul Eggert]

On 5/23/19 9:21 AM, Martin Sebor wrote:
> I'd rather discourage
> relying on the Glibc printf extension than remove the transformations
> or suppress the warning. 

I agree that this is a good way to go, as we can't keep fighting 
compilers forever. I wrote a patch implementing this suggestion and 
filed a bug report proposing it here:

https://sourceware.org/bugzilla/show_bug.cgi?id=24616