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Subject: Re: function prototype element ordering
From:   Joe Perches <joe@perches.com>
To:     Linus Torvalds <torvalds@linux-foundation.org>,
        Alexey Dobriyan <adobriyan@gmail.com>
Cc:     Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>, apw@canonical.com,
        Christoph Lameter <cl@linux.com>,
        Daniel Micay <danielmicay@gmail.com>,
        Dennis Zhou <dennis@kernel.org>, dwaipayanray1@gmail.com,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Linux-MM <linux-mm@kvack.org>,
        Lukas Bulwahn <lukas.bulwahn@gmail.com>,
        mm-commits@vger.kernel.org, Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Miguel Ojeda <ojeda@kernel.org>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Tejun Heo <tj@kernel.org>, Vlastimil Babka <vbabka@suse.cz>,
        "open list:DOCUMENTATION" <linux-doc@vger.kernel.org>
Date:   Wed, 22 Sep 2021 22:10:24 -0700
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On Wed, 2021-09-22 at 14:15 -0700, Linus Torvalds wrote:
> On Wed, Sep 22, 2021 at 12:24 AM Alexey Dobriyan <adobriyan@gmail.com> wrote:
> > 
> > Attributes should be on their own line, they can be quite lengthy.
> 
> No, no no. They really shouldn't.
> 
> First off, no normal code should use that "__attribute__(())" syntax
> anyway. It's ugly and big, and many of the attributes are
> compiler-specific anyway.
> 
> So the "quite lengthy" argument is bogus, because the actual names you
> should use are things like "__packed" or "__pure" or "__user" etc.
> 
> But the "on their own line" is complete garbage to begin with. That
> will NEVER be a kernel rule. We should never have a rule that assumes
> things are so long that they need to be on multiple lines.

I think it's not so much that lines are long, it's more that the
information provided by these markings aren't particularly useful to
a caller/user of a function.

Under what circumstance is a marking like __pure/__cold or __section
useful to someone that just wants to call a particular function?

A secondary reason why these should be separate or at least put
at the begining of a function declaration is compatibility with
existing tools like ctags.