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To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Trent Piepho <xyzzy@speakeasy.org>, Nick Piggin <nickpiggin@yahoo.com.au>,
       Satyam Sharma <ssatyam@cse.iitk.ac.in>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       David Howells <dhowells@redhat.com>,
       Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 6/8] i386: bitops: Don't mark memory as clobbered unnecessarily
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From: Andi Kleen <andi@firstfloor.org>
Date: 24 Jul 2007 22:37:43 +0200
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Linus Torvalds <torvalds@linux-foundation.org> writes:
> 
> (Yes, the "asm volatile" may do so too, but it's very unclear what the 
> "volatile" on the asm actually does, so ..)

Without the volatile they get completely optimized away :/
[tried that, cost a lot of debugging time -- empty string functions
cause a lot of strange side effects]

-Andi