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From:   Nick Desaulniers <ndesaulniers@google.com>
Date:   Fri, 31 Aug 2018 09:46:02 -0700
Message-ID: <CAKwvOdnyA=Y_+KnJrDc5mu7twTAEOMXvb8cAZhwzsXTi7a9sEA@mail.gmail.com>
Subject: Re: [PATCH v2] compiler.h: give up __compiletime_assert_fallback()
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Masahiro Yamada <yamada.masahiro@socionext.com>,
        Kees Cook <keescook@chromium.org>, sparse@chrisli.org,
        linux-sparse@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>,
        daniel.santos@pobox.com
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On Tue, Aug 28, 2018 at 4:00 PM Nick Desaulniers
<ndesaulniers@google.com> wrote:
>
> On Mon, Aug 27, 2018 at 1:42 PM Daniel Santos <daniel.santos@pobox.com> wrote:
> >
> > Hello Nick,
> >
> > On 08/27/2018 03:09 PM, Nick Desaulniers wrote:
> > >>> Let's give up __compiletime_assert_fallback().  This commit does not
> > >>> change the current behavior since it just rips off the useless code.
> > >> Clang is not the only target audience of
> > >> __compiletime_assert_fallback().  Instead of ripping out something that
> > >> may benefit builds with gcc 4.2 and earlier, why not override its
> > > Note that with commit cafa0010cd51 ("Raise the minimum required gcc
> > > version to 4.6") that gcc < 4.6 is irrelevant.
> >
> > Ah, I guess I'm not keeping up, that's wonderful news!  Considering that
> > I guess I would be OK with its removal, but I still think it would be
> > better if a similar mechanism to break the Clang build could be found.
>
> I'm consulting with our best language lawyers to see what combinations
> of _Static_assert and __builtin_constant_p would do the trick.

Linus,
Can this patch be merged in the meantime?

-- 
Thanks,
~Nick Desaulniers