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Message-ID: <36351fc3177bce273ecf47dd00b013306026aa2c.camel@perches.com>
Subject: Re: [RFC PATCH] compiler_attributes.h: Add 'fallthrough' pseudo
 keyword for switch/case use
From:   Joe Perches <joe@perches.com>
To:     Kees Cook <keescook@chromium.org>, Pavel Machek <pavel@ucw.cz>
Cc:     Neil Horman <nhorman@tuxdriver.com>,
        Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Borislav Petkov <bp@alien8.de>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        "Gustavo A . R . Silva" <gustavo@embeddedor.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Kan Liang <kan.liang@linux.intel.com>,
        Namhyung Kim <namhyung@kernel.org>,
        Jiri Olsa <jolsa@redhat.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Shawn Landden <shawn@git.icu>,
        "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" <x86@kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
Date:   Fri, 02 Aug 2019 09:16:04 -0700
In-Reply-To: <201908020907.4E056142@keescook>
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On Fri, 2019-08-02 at 09:09 -0700, Kees Cook wrote:
> On Fri, Aug 02, 2019 at 02:34:18PM +0200, Pavel Machek wrote:
> > I like the "fallthrough". It looks like "return" and it should, no
> > need to have __'s there..
> 
> Yeah, it would have the same feel as "break", "continue", "return"...
> 
> The only place I see this already used is in net/sctp/sm_make_chunk.c,
> as a label, which would be trivial to adjust...

Yeah.

From the RFC patch:

For allow compilation of a kernel that includes net/sctp, this patch
also requires a rename of the use of fallthrough as a label in
net/sctp/sm_make_chunk.c that was submitted as:

https://lore.kernel.org/lkml/e0dd3af448e38e342c1ac6e7c0c802696eb77fd6.1564549413.git.joe@perches.com/