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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Mon, 29 May 2023 20:06:33 -0400
Message-ID: <CAHk-=whEsr6fuVSdsoNPokLR2fZiGuo_hCLyrS-LCw7hT_N7cQ@mail.gmail.com>
Subject: Re: [PATCH v2 0/2] Lock and Pointer guards
To:     Ian Lance Taylor <iant@google.com>
Cc:     Paolo Bonzini <pbonzini@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>, keescook@chromium.org,
        gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org,
        ojeda@kernel.org, ndesaulniers@google.com, mingo@redhat.com,
        will@kernel.org, longman@redhat.com, boqun.feng@gmail.com,
        juri.lelli@redhat.com, vincent.guittot@linaro.org,
        dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com,
        mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com,
        paulmck@kernel.org, frederic@kernel.org, quic_neeraju@quicinc.com,
        joel@joelfernandes.org, josh@joshtriplett.org,
        mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com,
        rcu@vger.kernel.org, tj@kernel.org, tglx@linutronix.de
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On Mon, May 29, 2023 at 5:27=E2=80=AFPM Ian Lance Taylor <iant@google.com> =
wrote:
>
> It was a while ago, but I expect that I was just thinking of the
> implementation.  I agree that the documentation could be clearer.  I
> filed https://gcc.gnu.org/PR110029.

Thanks. I think we can proceed with the assumption that it's all
clearly ordered. Even when the scopes are explicit (ie actual separate
block scopes for the variables and no shared scope), doing a 'return'
(or break out of a loop) will obviously exit multiple scopes at once,
so it would be good to have it documented that the cleanup is always
in that reverse order by scope and declaration order within a scope.

I guess I should check with the clang people too.

              Linus