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Subject: Re: [PATCH] compiler_types: mark __compiletime_assert failure as
 __noreturn
To:     Nick Desaulniers <ndesaulniers@google.com>,
        Peter Zijlstra <peterz@infradead.org>
Cc:     Miguel Ojeda <ojeda@kernel.org>,
        Nathan Chancellor <nathan@kernel.org>,
        Kees Cook <keescook@chromium.org>,
        linux-kernel@vger.kernel.org, llvm@lists.linux.dev,
        Linus Torvalds <torvalds@linux-foundation.org>
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From:   Rasmus Villemoes <linux@rasmusvillemoes.dk>
Message-ID: <d1c957c4-a2df-935c-2992-3540f05fb110@rasmusvillemoes.dk>
Date:   Fri, 15 Oct 2021 10:11:16 +0200
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On 14/10/2021 19.48, Nick Desaulniers wrote:
> On Thu, Oct 14, 2021 at 8:02 AM Peter Zijlstra <peterz@infradead.org> wrote:
>>

> I'm not sure how worthwhile that yakshave would be, 

A yakshave that would be worthwhile is to kill off the macro
compiletime_assert() completely - three is a crowd. It sounds like it
would be implemented in terms of _Static_assert, but it's actually
__attribute__(error). We can fold the definition of compiletime_assert
into BUILD_BUG_ON_MSG.

The users in rwonce.h should just be changed to static_assert, and then
there are very few random users left, which can either be static_assert
or BUILD_BUG_ON_MSG.

Why do we even have a no-op version if !__OPTIMIZE__? AFAIK there's no
CONFIG_O0 option, and such a build wouldn't be interesting at all - it
can't be expected to boot, and it would likely throw warnings left and
right.

Rasmus