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From:   Arnd Bergmann <arnd@kernel.org>
Date:   Tue, 1 Mar 2022 15:44:59 +0100
Message-ID: <CAK8P3a160RneN60cA2apHVt1D6oiV2KprG=uJ2mJwVvrR3z4pg@mail.gmail.com>
Subject: Re: [PATCH] [v2] Kbuild: move to -std=gnu11
To:     Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc:     Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>,
        Arnd Bergmann <arnd@arndb.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Masahiro Yamada <masahiroy@kernel.org>, llvm@lists.linux.dev,
        Jonathan Corbet <corbet@lwn.net>,
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On Tue, Mar 1, 2022 at 11:43 AM Miguel Ojeda
<miguel.ojeda.sandonis@gmail.com> wrote:
>
> On Mon, Feb 28, 2022 at 11:32 AM Arnd Bergmann <arnd@kernel.org> wrote:
> >
> > -under ``-std=gnu89`` [gcc-c-dialect-options]_: the GNU dialect of ISO C90
> > -(including some C99 features). ``clang`` [clang]_ is also supported, see
> > +under ``-std=gnu11`` [gcc-c-dialect-options]_: the GNU dialect of ISO C11
> > +(including some C17 features). ``clang`` [clang]_ is also supported, see
>
> I think the "(including some C17)" bit would not make much sense
> anymore. There were no major changes in C17 and GCC implements
> `-std=c11` and `-std=c17` as basically the same thing according to the
> docs (and GNU extensions apply equally to both, I would assume).

Ok, changed now.

> When I wrote the "(including some C99 features)" I meant that GCC
> implemented some C99 features as extensions in C90 mode, and the
> kernel used some of those (e.g. the now gone VLAs).

I suppose it's still true for some c2x features (static_assert, fallthrough,
binary literals, ...), but it seems easier to just leave it out.

> With that changed, for `programming-language.rst`:
>
> Reviewed-by: Miguel Ojeda <ojeda@kernel.org>

Thanks.