Re: [PATCH] x86/syscalls: Mark expected switch fall-throughs

From: Thomas Gleixner <tglx@linutronix.de>
To: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Cc: "Gustavo A. R. Silva" <garsilva@embeddedor.com>,
	Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
	x86@kernel.org, LKML <linux-kernel@vger.kernel.org>,
	Kees Cook <keescook@chromium.org>
Subject: Re: [PATCH] x86/syscalls: Mark expected switch fall-throughs
Date: Tue, 28 Nov 2017 21:11:55 +0100 (CET)	[thread overview]
Message-ID: <alpine.DEB.2.20.1711282109060.2222@nanos> (raw)
In-Reply-To: <20171128190032.2b1fa464@alans-desktop>

On Tue, 28 Nov 2017, Alan Cox wrote:

> > I have no idea who came up with that brilliant idea of parsing comments in
> > the code. It's so simple to make this parser completely fail that it's not
> 
> Stephen Johnson (author of the V7 portable C compiler), which is where
> it's from (the lint tool). He also wrote yacc so he does know a bit about
> parsers 8).

I don't doubt that.

> > even funny anymore.
> 
> The notation in question has been standard in tools like lint since the
> end of the 1970s

Fair enough.

Still that does not make the GCC implementation which defaults to take 'any
comment' as valid any better and does not solve other parsing issues which
have been pointed out in various GCC bugs. Using the macro annotation is
distinct and has no ifs and buts.

Thanks,

	tglx