From: Junio C Hamano <gitster@pobox.com>
Date: Wed, 19 Jan 2022 00:22:05 GMT
Subject: Re: [PATCH] Makefile: FreeBSD cannot do C99-or-below build
Message-ID: <xmqqzgnspob6.fsf@gitster.g>
In-Reply-To: <220119.861r14pomb.gmgdl@evledraar.gmail.com>

Ævar Arnfjörð Bjarmason <avarab@gmail.com> writes:

> On Tue, Jan 18 2022, Neeraj Singh wrote:
>
>> The approach of building with C11 on FreeBSD is a good one
>> compared to trying to hack around the headers.
>
> The "hack around the headers" suggests that you've seen my
> alternate[1]....
>
>> It appears more like a compiler bug that's being worked around
>> here. The FreeBSD header supposedly uses a GCC extension if the
>> C standard version is less than C11.  See: 
>> https://github.com/freebsd/freebsd-src/blob/1e7b5f950b2d54ddb257d008592563c4d753aa54/sys/sys/cdefs.h#L317
>
> ...which discusses how the line you're linking to here and
> __has_extension() interact, it's not a compiler bug, unless I'm missing
> something.
>
> I.e. it's just a FreeBSD include asking the compiler the wrong question
> and/or not suppressing the warning (e.g. via "#pragma clang
> system_header").

Yup, I do agree with you that this looks more like a bug in the
header files.