Re: [KJ][RFC][PATCH] BIT macro cleanup

On Fri, Feb 23, 2007 at 01:44:41PM +0530, Milind Choudhary wrote:

Hi all
	working towards the cleanup of BIT macro,
I've added one to <linux/bitops.h> & cleaned some obvious users.

include/linux/input.h also has a BIT macro
which does a wrap
so currently i've done something like

+#undef BIT
#define BIT(nr)        (1UL << ((nr) % BITS_PER_LONG))

 
Since the previous definition of

#define BIT(nr)		(1UL << (nr))

gives the same results as the above one for all reasonable usage
scenarios (you don't want to supply nr larger than BITS_PER_LONG),
why not just use the modulo version everywhere?

The only problem I see is that the compiler would not warn where nr IS
too large.

-- 
Vojtech Pavlik
Director SuSE Labs