Re: FYI: getopt in /usr/src/contrib/diff/lib/getopt.h vs. /usr/obj/usr/src/arm64.aarch64/tmp/usr/include/unistd.h : reported as incompatible with future C23 use

On Sat, 8 Nov 2025 at 11:10, Mark Millard <marklmi@yahoo.com> wrote:
>
> In file included from /usr/src/contrib/diff/src/diff3.c:32:
> /usr/src/contrib/diff/lib/getopt.h:154:12: warning: a function declaration without a prototype is deprecated in all versions of C and is treated as a zero-parameter prototype in C23, conflicting with a previous declaration [-Wdeprecated-non-prototype]
>   154 | extern int getopt ();
>       |            ^
> /usr/obj/usr/src/arm64.aarch64/tmp/usr/include/unistd.h:384:6: note: conflicting prototype is here
>   384 | int      getopt(int, char * const [], const char *);
>       |          ^

I think we can just remove contrib/diff/lib/getopt.h and use the
system header. I've opened a review to do that in
https://reviews.freebsd.org/D53802