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Date: Sat, 25 Nov 2006 15:05:00 -0800 (PST)
Message-Id: <20061125.150500.14841768.davem@davemloft.net>
To: rdreier@cisco.com
Cc: akpm@osdl.org, linux-kernel@vger.kernel.org, openib-general@openib.org,
       tom@opengridcomputing.com
Subject: Re: [PATCH] Avoid truncating to 'long' in ALIGN() macro
From: David Miller <davem@davemloft.net>
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From: Roland Dreier <rdreier@cisco.com>
Date: Sat, 25 Nov 2006 14:56:22 -0800

>  > Perhaps a better way to fix this is to use
>  > typeof() like other similar macros do.
> 
> I tried doing
> 
> #define ALIGN(x,a)				\
> 	({					\
> 		typeof(x) _a = (a);		\
> 		((x) + _a - 1) & ~(_a - 1);	\
> 	})
> 
> but that won't compile because of <net/neighbour.h>:

You would need to also cast the constants with typeof() to.

But yes, given the array sizing case in the neighbour code,
perhaps we can use your original patch for now.  Feel free
to push that to Linus.