1 << BITS_PER_UNIT

[Alexandre Oliva]

Richard Earnshaw <rearnsha@arm.com> writes:

> I wasn't suggesting ((1 << x) - 1) == (2 << (x - 1)), that is obviously 
> false, but (1 << x) == (2 << (x - 1)).  Do some elementary math.

Ah, now I get it.

> The point is that (1 << BITS_PER_UNIT) - 1 gets you a warning, but
> (2 << (BITS_PER_UNIT - 1)) - 1 gives the same result but no warning, and 
> is well within the spec since (BITS_PER_UNIT - 1) is less than the word 
> size.

Right.  One more reason for us to stick with a macro, heh?

-- 
Alexandre Oliva
mailto:oliva@dcc.unicamp.br mailto:oliva@gnu.org mailto:aoliva@acm.org
http://www.dcc.unicamp.br/~oliva
Universidade Estadual de Campinas, SP, Brasil