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In-Reply-To: <20240320124207.0c127947@canb.auug.org.au>
From: Barry Song <21cnbao@gmail.com>
Date: Wed, 20 Mar 2024 16:24:30 +1300
Message-ID: <CAGsJ_4zpXwVEhsdffoZVBVWiwT4Lw2qEMrW-X92ib=kv=9Yx9g@mail.gmail.com>
Subject: Re: [PATCH] Documentation: coding-style: ask function-like macros to
 evaluate parameters
To: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: corbet@lwn.net, workflows@vger.kernel.org, linux-doc@vger.kernel.org, 
	linux-kernel@vger.kernel.org, Barry Song <v-songbaohua@oppo.com>, 
	Andrew Morton <akpm@linux-foundation.org>, Chris Zankel <chris@zankel.net>, 
	Huacai Chen <chenhuacai@loongson.cn>, Herbert Xu <herbert@gondor.apana.org.au>, 
	Guenter Roeck <linux@roeck-us.net>, Max Filippov <jcmvbkbc@gmail.com>
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Hi Stephen,
Thanks for reviewing.

On Wed, Mar 20, 2024 at 2:42=E2=80=AFPM Stephen Rothwell <sfr@canb.auug.org=
au> wrote:
>
> Hi Barry,
>
> On Wed, 20 Mar 2024 13:16:56 +1300 Barry Song <21cnbao@gmail.com> wrote:
> >
> > diff --git a/Documentation/process/coding-style.rst b/Documentation/pro=
cess/coding-style.rst
> > index 9c7cf7347394..8065747fddff 100644
> > --- a/Documentation/process/coding-style.rst
> > +++ b/Documentation/process/coding-style.rst
> > @@ -827,6 +827,13 @@ Macros with multiple statements should be enclosed=
 in a do - while block:
> >                               do_this(b, c);          \
> >               } while (0)
> >
> > +Function-like macros should evaluate their parameters, for unused para=
meters,
> > +cast them to void:
> > +
> > +.. code-block:: c
> > +
> > +     #define macrofun(a) do { (void) (a); } while (0)
> > +
>
> Maybe add some comment about using a static inline function for these
> simple versions instead, if at all possible, (it is suggested just
> above this section) since that will still type check arguments.

right, what about adding the below section together with the above (void) c=
ast?

+Another approach could involve utilizing a static inline function to repla=
ce
+the macro.:
+
+.. code-block:: c
+
+       static inline void fun(struct foo *foo)
+       {
+       }
+

>
> --
> Cheers,
> Stephen Rothwell

Thanks
Barry