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From:   Ard Biesheuvel <ardb@kernel.org>
Date:   Sun, 28 Jun 2020 21:26:45 +0200
Message-ID: <CAMj1kXFfLb44ifgNqBR9WM5T6sT6ekqS8cYdvbuhvs5mqcD+tw@mail.gmail.com>
Subject: Re: [GIT PULL] EFI fixes
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Ingo Molnar <mingo@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Borislav Petkov <bp@alien8.de>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        linux-efi <linux-efi@vger.kernel.org>
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On Sun, 28 Jun 2020 at 20:57, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> On Sun, Jun 28, 2020 at 11:26 AM Ingo Molnar <mingo@kernel.org> wrote:
> >
> > - Fix build regression on v4.8 and older
>
> Interesting.
>
> It's perhaps yet another reason to just skip gcc-4.8 too, since
> apparently 4.9 works.
>

+1

> gcc-4.9 really has a lot of advantages. It's where (I think) gcc
> basically supports all C11 things, including _Generic() but also
> __auto_type.
>
> So if we just say that we only care about gcc-4.9 upwards, it frees us
> to clean up some (really) old constructions where we've been using
> macros with sizeof and/or typeof, and make the code potentially rather
> more readable and often more compact.
>
> Yeah, I know we _just_ made the minimum compiler version be 4.8, but I
> do get the feeling that we should just have bitten the bullet and gone
> all the way to 4.9.
>
> Arnd, what was the reason for 4.8 support? I'm assuming there's some
> sad unfortunate distro that still uses that ancient compiler..
>

Arnd may know more, but I know one of the reasons 4.8 is significant
is because RHEL 7 uses it, which will go EOL in 2024.

> Ok, ok, 4.9 isn't exactly new either (4.9.0 released May 2014, and
> final 4.9 release was 2016), but 4.9 really from a feature angle is a
> much saner thing than 4.8.
>
> Afaik, the main "interesting" part of gcc-4.8 was that it was when gcc
> switched over to be built as C++. That's perhaps a huge milestone for
> gcc itself, but not necessarily for the users..
>
> Arnd? You're the one who tends to keep track of these things..
>
>              Linus