From: Collin Funk <collin.funk1@gmail.com>
Date: Tue, 03 Jun 2025 04:05:43 GMT
Subject: Re: [PATCH] compat: fixes for header handling with OpenBSD / NetBSD
Message-ID: <87y0u9qxk8.fsf@gmail.com>
In-Reply-To: <47c58a78-d38b-4170-87fc-c9332618d0da@comstyle.com>

Brad Smith <brad@comstyle.com> writes:

>> Why remove this definition? I think it might be useful on some older
>> systems and seems harmless otherwise.
>
> _XOPEN_SOURCE restricts the build environment. _NETBSD_SOURCE is added
> to counteract
> _XOPEN_SOURCE. Not setting it in the first place provides everything
> by default.
>
> I was removing it as it should no longer be necessary.
>
> But as said, it is harmless. I can leave it in if desired.

In Autoconf's AC_USE_SYSTEM_EXTENSIONS it is defined with the comment:

    /* Enable general extensions on NetBSD.
       Enable NetBSD compatibility extensions on Minix.  */

I would prefer just leaving it for any old system that may need it. Or
in case git uses features from a recent standard that might still be
hidden as a NetBSD extension.

For example, POSIX.1-2024 has been released, but most functions added
there are still under _GNU_SOURCE in current glibc.

Collin