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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Fri, 16 Jul 2021 12:26:27 -0700
Message-ID: <CAHk-=wjGfJPROMSdC8n1xnvyQzxWiz2pXV9E6OE_vpti7rCdZQ@mail.gmail.com>
Subject: Re: [GIT PULL] fallthrough fixes for Clang for 5.14-rc2
To:     Nathan Chancellor <nathan@kernel.org>
Cc:     "Gustavo A. R. Silva" <gustavo@embeddedor.com>,
        "Gustavo A. R. Silva" <gustavoars@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Kees Cook <keescook@chromium.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        clang-built-linux <clang-built-linux@googlegroups.com>
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On Fri, Jul 16, 2021 at 12:18 PM Nathan Chancellor <nathan@kernel.org> wrote:
>
> Hence why I suggested -Wimplicit-fallthrough-unreachable.

As long as it's a warning that the kernel would never set, that's fine.

I think it's an entirely bogus warning, but at some point as long as
we don't need to care about it, we can happily ignore it.

Or just continue to say "clang is spewing bogus warnings, don't use it".

But the sane naming for that warning should certainly not have
anything at all to do with "implicit". Quite the reverse. The warning
is about an  _explicit_ fallthrough being unreachable, and as such
thje warning name should reflect that.

So make it just "-Wfallthrough-unreachable" (maybe even
"-Wexplicit-..") to allow people who want that pointless warning to
enable it.

               Linus