Re: [PATCH] video: constify geode ops structures

From: Joe Perches <joe@perches.com>
To: Kees Cook <keescook@chromium.org>, Christoph Hellwig <hch@infradead.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>,
	Julia Lawall <Julia.Lawall@lip6.fr>,
	Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>,
	kernel-janitors@vger.kernel.org,
	Tomi Valkeinen <tomi.valkeinen@ti.com>,
	linux-geode@lists.infradead.org, linux-fbdev@vger.kernel.org,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] video: constify geode ops structures
Date: Tue, 10 Nov 2015 12:49:29 -0800	[thread overview]
Message-ID: <1447188569.2701.91.camel@perches.com> (raw)
In-Reply-To: <CAGXu5j+59jPqd5QWq38KH--i=gBzq2d5j_Z0c2ygG=pfr2+tzw@mail.gmail.com>

On Tue, 2015-11-10 at 12:34 -0800, Kees Cook wrote:
> We can't make everything work just by static
> analyzers and checkpatch.pl runs (meaning the "backstop" comment
> above).
> 
> Additionally, having the plugin infrastructure gets us the ability to
> do things that aren't presently possible (see the thread on the
> initify plugin, which can't be done in source alone).

#define __do_const __attribute__((do_const))
...
#ifndef __do_const
#define __do_const
#endif

I think it's always better for the reader to know that a
const struct declaration is used over a non-const struct
when the compiler, via plug-in extension, could convert
the declaration to const.

Is there a warning/info message produced by gcc and the
plug-in when a non-const declaration is converted to
const because of this attribute?