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From: David Woodhouse <dwmw2@infradead.org>
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To: Alan Cox <alan@lxorguk.ukuu.org.uk>
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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 
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alan@lxorguk.ukuu.org.uk said:
>  Possibly not - volatile doesnt guarantee the compiler won't do
> 	x = 1
> 	add *p into x
> 	store x into *p

Er, AIUI 'volatile' guarantees that '*p++' will do precisely that. It's a 
load, an add and a store, and the rules about volatile mean that the load 
and the store _must_ be separate.

--
dwmw2


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