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Date: Thu, 25 Aug 2005 14:16:17 -0700 (PDT)
From: Vadim Lobanov <vlobanov@speakeasy.net>
To: Christopher Friesen <cfriesen@nortel.com>
cc: linux-kernel@vger.kernel.org, tom.anderl@gmail.com
Subject: Re: [OT] volatile keyword
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On Thu, 25 Aug 2005, Christopher Friesen wrote:

> Vadim Lobanov wrote:
>
> > I'm positive I'm doing something wrong here. In fact, I bet it's the
> > volatile cast within the loop that's wrong; but I'm not sure how to do
> > it correctly. Any help / pointers / discussion would be appreciated.
>
> You need to cast is as dereferencing a volatile pointer.
>
> Chris
>

I figured it was something along these lines. In that case, is the
following code (from kernel/posix-timers.c) really doing the right
thing?

do
    expires = timr->it_timer.expires;
while ((volatile long) (timr->it_timer.expires) != expires);

Seems it's casting the value, not the pointer.

-VadimL