[PATCH 16/17] Regex: Define __USE_GNU for non-GLIBC systems.

[arnold@skeeve.com]

Joseph Myers <joseph@codesourcery.com> wrote:

> On Fri, 8 Dec 2017, Arnold Robbins wrote:
>
> > This patch defines __USE_GNU for non-GLIBC systems. For example, *BSD
> > need it.
>
> _LIBC refers to glibc being *built*.  This change would cause the header 
> to expose inappropriate symbols when used in an installation of glibc.
>
> -- 
> Joseph S. Myers
> joseph@codesourcery.com

There don't seem to be other uses of _LIBC in the regex.h header.
All I know is that the __USE_GNU is needed on non-GLIBC systems.
Removing that bit doesn't affect compiling on Linux, nor does having
it there.

So, I don't see the harm in it, but I'm not a GLIBC guy, so I'm
probably still missing something.

Arnold