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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Tue, 6 Jun 2023 06:17:33 -0700
Message-ID: <CAHk-=wi-RyoUhbChiVaJZoZXheAwnJ7OO=Gxe85BkPAd93TwDA@mail.gmail.com>
Subject: Re: [PATCH v2 0/2] Lock and Pointer guards
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     keescook@chromium.org, gregkh@linuxfoundation.org,
        pbonzini@redhat.com, linux-kernel@vger.kernel.org,
        ojeda@kernel.org, ndesaulniers@google.com, mingo@redhat.com,
        will@kernel.org, longman@redhat.com, boqun.feng@gmail.com,
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On Tue, Jun 6, 2023 at 2:43=E2=80=AFAM Peter Zijlstra <peterz@infradead.org=
> wrote:
>
> ( GCC refuses to accept _Pragma() inside an expression.

If we really want this all, I think we'd just stop using
-Wdeclaration-after-statement entirely.

There are other uses for it, and people have asked for mixing
declarations and code before.

I think that particular straightjacket has been a good thing, but I
also think that it's ok to just let it go as a hard rule, and just try
to make it a coding style issue for the common case, but allow mixed
declarations and code when it makes sense.

For the whole "automatic release case it definitely makes sense, but
it's not like it isn't possible useful elsewhere. I just don't want
for it to become some global pattern for everything.

That said, I still don't understand why you lke the name "guard" for
this.  I understand not liking "auto", but "guard" doesn't seem any
better. In fact, much worse. Guarded expressions means something
completely different both in real life and in computer science.

I'm assuming there's some history there, but it makes no sense to me
as a name here.

              Linus