Re: page_launder() bug

J . A . Magallon
2001-05-07T19:03:01Z

On 05.07 Helge Hafting wrote:
> Tobias Ringstrom wrote:
> >
> > On Sun, 6 May 2001, David S. Miller wrote:
> > > It is the most straightforward way to make a '1' or '0'
> > > integer from the NULL state of a pointer.
> >
> > But is it really specified in the C "standards" to be exctly zero or one,
> > and not zero and non-zero?
>
> !0 is 1. !(anything else) is 0. It is zero and one, not
> zero and "non-zero". So a !! construction gives zero if you have
> zero, and one if you had anything else. There's no doubt about it.
> >

Isn't this asking for trouble with the optimizer ? It could kill both
!!. Using that is like trusting on a certain struct padding-alignment.

--
J.A. Magallon # Let the source be with you...
mailto:jamagallon@able.es
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