Re: RFC: booleans and the kernel

From: Oliver Xymoron (oxymoron@waste.org)
Date: Thu Jan 24 2002 - 15:06:23 EST


On Thu, 24 Jan 2002, Jeff Garzik wrote:

> Oliver Xymoron wrote:
> > On Thu, 24 Jan 2002, Jeff Garzik wrote:
> > > Where variables are truly boolean use of a bool type makes the
> > > intentions of the code more clear. And it also gives the compiler a
> > > slightly better chance to optimize code [I suspect].
> >
> > Unlikely. The compiler can already figure this sort of thing out from
> > context.
>
> X, true, and false are of type int.
> If one tests X==false and then later on tests X==true, how does the
> compiler know the entire domain has been tested?

Because you never test against X==true. You always test X!=false. This is
the C way.

> Or a switch statement... if both true and false are covered,
> there is no need for a 'default'.

Your cases are false and default.

-- 
 "Love the dolphins," she advised him. "Write by W.A.S.T.E.."

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