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Date: Fri, 25 Jul 2008 14:14:04 -0400
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Harvey Harrison <harvey.harrison@gmail.com>
CC: Linus Torvalds <torvalds@linux-foundation.org>,
       David Miller <davem@davemloft.net>,
       Andrew Morton <akpm@linux-foundation.org>,
       LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] byteorder: force in-place endian conversion to always
 evaluate args
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Harvey Harrison wrote:
> David Miller reported breakage in ide when the in-place byteorder helpers
> were used as the macros do not always evaluate their args which led to
> an infinite loop.
> 
> Just make them functions to ensure they always do so.

> -#define __cpu_to_be64s(x) do {} while (0)

For what it's worth, the way to write a macro like this:

#define __cpu_to_be64s(x) ((void)(x))

	-hpa