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From: Arnd Bergmann <arnd@arndb.de>
To: Lubos Lunak <l.lunak@suse.cz>
Subject: Re: [PATCH][RESEND] do not redefine userspace's NULL #define
Date: Sat, 14 Apr 2012 09:30:39 +0000
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Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Peter Seebach <peter.seebach@windriver.com>,
        Andrew Morton <akpm@linux-foundation.org>,
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On Saturday 14 April 2012, Lubos Lunak wrote:
>  That's what the original version of my patch did, but Arnd pointed out that 
> other exported headers might use NULL and thus not be self-contained in 
> userspace after this change, breaking backwards source compatibility. But I'd 
> expect such breakages to be rather unlikely (stddef.h is probably pulled in 
> by pretty much everything), so if you're fine with it, I'm ok with this 
> solution too.

Yes, I stand corrected on that one. I have checked that actually no exported
headers rely on the definition of NULL, so your original patch is good.

Acked-by: Arnd Bergmann <arnd@arndb.de>