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Date:   Wed, 18 Nov 2020 12:12:26 -0600
From:   Segher Boessenkool <segher@kernel.crashing.org>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Nick Desaulniers <ndesaulniers@google.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Sami Tolvanen <samitolvanen@google.com>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Matt Mullins <mmullins@mmlx.us>,
        Ingo Molnar <mingo@redhat.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Dmitry Vyukov <dvyukov@google.com>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>, Yonghong Song <yhs@fb.com>,
        Andrii Nakryiko <andriin@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@chromium.org>,
        netdev <netdev@vger.kernel.org>, bpf <bpf@vger.kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        linux-toolchains@vger.kernel.org
Subject: Re: violating function pointer signature
Message-ID: <20201118181226.GK2672@gate.crashing.org>
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On Wed, Nov 18, 2020 at 12:17:30PM -0500, Steven Rostedt wrote:
> I could change the stub from (void) to () if that would be better.

Don't?  In a function definition they mean exactly the same thing (and
the kernel uses (void) everywhere else, which many people find clearer).

In a function declaration that is not part of a definition it means no
information about the arguments is specified, a quite different thing.

This is an obsolescent feature, too.  Many many years from now it could
perhaps mean the same as (void), just like in C++, but not yet.


Segher