Subject: Re: [PATCH] git-compat-util.h: Bump _XOPEN_SOURCE on OpenBSD

From: Junio C Hamano <[email-masked]>
Date: Fri, 21 Feb 2025 18:07:49 -0800

Audrey Dutcher <[email-masked]> writes:

>> Is this a recent regression?  Blaming these two line ranges ...
>>
>> >
>> > [1] https://github.com/openbsd/src/blob/6a403588e27467d1f271831ca1de62a3befea6a0/include/stdio.h#L236-L237
>> > [2] https://github.com/openbsd/src/blob/6a403588e27467d1f271831ca1de62a3befea6a0/sys/sys/cdefs.h#L299-L302
>>
>> ... in the OpenBSD repository says they haven't changed for many
>> years, and I am wondering what triggered this all of a sudden.
>>
>> If we know how we used to have no issue, in addition to how we now
>> have issue with the current OpenBSD (which you outlined very well
>> above), and when the situation changed, please add to the proposed
>> log message.  That would help people on OpenBSD to decide when they
>> want to upgrade their copy of Git.
>
> The thing that changed was the release of clang 19, which enabled the
> mentioned Werror by default. This is showing up now because I am
> experimenting with building software for OpenBSD through nixpkgs,
> which prefers the most recent version of everything. I am not sure
> what of this is appropriate to add to the commit message.

When reviewers help me by asking questions on what I wrote in a
proposed commit log message, a trick I try to stick to is to pretend
that they are not who are asking, but the question is coming from
those who read the commit in the future and they do not have an easy
way to ask me the question.  The only way for me to help them is by
updating the message they would read when they see the commit (IOW,
I unfortunately would not have the luxury of going back-and-forth).

In this case, if I were writing the message for the commit, "Unlike
versions of clang earlier than 19, clang 19, enables the
'-Werror=...' option by default...", would be something that would
help them.  And as Peff mentioned elsewhere in the thread, "When
HAVE_GETDELIM is enabled" would also be an important clue to leave.

Thanks.