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Date: Mon, 8 Aug 2005 10:47:21 -0700
From: Marc Singer <elf@buici.com>
To: Marcel Holtmann <marcel@holtmann.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] spi
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References: <1121025679.3008.10.camel@spirit> <1123492338.4762.96.camel@diimka.dev.rtsoft.ru> <20050808145544.GB6478@kroah.com> <1123522536.7751.51.camel@pegasus>
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On Mon, Aug 08, 2005 at 07:35:36PM +0200, Marcel Holtmann wrote:
> > > +	if (NULL == dev || NULL == driver) {
> > 
> > Put the variable on the left side, gcc will complain if you incorrectly
> > put a "=" instead of a "==" here, which is all that you are defending
> > against with this style.
> 
> I think in this case the preferred way is
> 
> 	if (!dev || !driver) {
> 

That's not a guaranteed equivalence in the C standard.  Null pointers
may not be zero.  I don't think we have any targets that work this
way, however there is nothing wrong with explicitly testing for NULL.