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Subject: Re: [PATCH] [2.5] asm-generic/atomic.h and changes to arm, parisc,
	mips, m68k, sh, cris to use it
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Luca Barbieri <ldb@ldb.ods.org>
Cc: Roman Zippel <zippel@linux-m68k.org>,
       Linux-Kernel ML <linux-kernel@vger.kernel.org>
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On Thu, 2002-08-08 at 23:40, Luca Barbieri wrote:
> > The compiler can cache the value in a register
> It shouldn't since it is volatile and the machine has instructions with
> memory operands.

I'm curious what part of C99 guarantees that it must generate

	add 1 to memory

not

	load memory
	add 1
	store memory

It certainly guarantees not to cache it for use next statement, but does
it actually persuade the compiler to use direct operations on memory ?

I'm not a C99 language lawyer but genuinely curious

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