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Date: Thu, 19 Oct 2006 21:59:54 -0700
From: Andrew Morton <akpm@osdl.org>
To: Matthew Wilcox <matthew@wil.cx>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Minor fixes to generic do_div
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On Thu, 19 Oct 2006 21:34:00 -0600
Matthew Wilcox <matthew@wil.cx> wrote:

> +/* The unnecessary pointer compare is there
> + * to check for type safety (n must be 64bit)
> + */
> +# define do_div(n,base) ({				\
> +	uint32_t __base = (base);			\
> +	uint32_t __rem;					\
> +	(void)(((typeof((n)) *)0) == ((uint64_t *)0));	\
> +	__rem = ((uint64_t)(n)) % __base;		\
> +	(n) = ((uint64_t)(n)) / __base;			\
> +	__rem;						\
>   })

Can we use typecheck(), from include/linux/kernel.h?