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From: "Michael S. Tsirkin" <mst@redhat.com>
To: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Rusty Russell <rusty@rustcorp.com.au>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: Why does test_bit() take a volatile addr?
Date: Mon, 16 Sep 2013 10:26:03 +0300	[thread overview]
Message-ID: <20130916072603.GA11007@redhat.com> (raw)
In-Reply-To: <20130916165344.144f0d0f1b58111f1c8c87cc@canb.auug.org.au>

On Mon, Sep 16, 2013 at 04:53:44PM +1000, Stephen Rothwell wrote:
> Hi Rusty,
> 
> On Mon, 16 Sep 2013 13:38:35 +0930 Rusty Russell <rusty@rustcorp.com.au> wrote:
> >
> > Predates git, does anyone remember the rationale?
> > 
> > ie:
> >         int test_bit(int nr, const volatile unsigned long *addr)
> 
> Because we sometimes pass volatile pointers to it and gcc will complain
> if you pass a volatile to a non volatile  (I think).

Where are these? I did git grep -W test_bit and looked for volatile,
couldn't find anything.

> -- 
> Cheers,
> Stephen Rothwell                    sfr@canb.auug.org.au



  reply	other threads:[~2013-09-16  7:24 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-09-16  4:08 Why does test_bit() take a volatile addr? Rusty Russell
2013-09-16  6:53 ` Stephen Rothwell
2013-09-16  7:26   ` Michael S. Tsirkin [this message]
2013-09-16  8:02     ` Stephen Rothwell
2013-09-16  8:47       ` Michael S. Tsirkin
2013-09-16  8:20 ` Geert Uytterhoeven
2013-09-16  8:37 ` Michael S. Tsirkin
2013-09-16  8:40 ` Oliver Neukum
2013-09-16  8:44   ` Michael S. Tsirkin
2013-09-16  8:49     ` Oliver Neukum
2013-09-16 11:59 ` Linus Torvalds
2013-09-22 21:37 ` Rob Landley
2013-09-23  1:13   ` Rusty Russell

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