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Message-ID: <45e070039e66b1cb1490a78d4805bc73cc09f571.camel@perches.com>
Subject: Re: [PATCH] Use fall-through attribute rather than magic comments
From:   Joe Perches <joe@perches.com>
To:     Pavel Machek <pavel@ucw.cz>, Shawn Landden <shawn@git.icu>
Cc:     linux-kernel@vger.kernel.org,
        "Gustavo A . R . Silva" <gustavo@embeddedor.com>,
        Andy Whitcroft <apw@canonical.com>
Date:   Mon, 17 Jun 2019 09:25:56 -0700
In-Reply-To: <20190617155643.GA32544@amd>
References: <20190316033841.7659-1-shawn@git.icu>
         <20190617155643.GA32544@amd>
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On Mon, 2019-06-17 at 17:56 +0200, Pavel Machek wrote:
> Hi!
> 
> > +/*
> > + *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#index-Wimplicit-fallthrough
> > + *   gcc: https://developers.redhat.com/blog/2017/03/10/wimplicit-fallthrough-in-gcc-7/
> > + */
> > +#if __has_attribute(__fallthrough__)
> > +# define __fallthrough                    __attribute__((__fallthrough__))
> > +#else
> > +# define __fallthrough
> > +#endif
> 
> Is it good idea to add the __'s ? They look kind of ugly. 

Dunno.

I agree it's kind of ugly, but it should always work.

I think the generic problem is introducing a new unprefixed
reserved identifier.  Underscored identifiers are reserved.

There is already a fallthrough: label used in kernel sources
in net/sctp/sm_make_chunk.c that should probably be changed.