Re: page_launder() bug

[Horst von Brand <vonbrand@inf.utfsm.cl>]

"David S. Miller" <davem@redhat.com> said:
> Jonathan Morton writes:
>  > >-			 page_count(page) == (1 + !!page->buffers));
>  > 
>  > Two inversions in a row?
> 
> It is the most straightforward way to make a '1' or '0'
> integer from the NULL state of a pointer.

IMVHO, it is clearer to write:

  page_count(page) == 1 + (page->buffers != NULL)

At least, the original poster wouldn't have wondered, and I wouldn't have
had to think a bit to find out what it meant... If gcc generates worse code
for this, it should be fixed.
-- 
Dr. Horst H. von Brand                       mailto:vonbrand@inf.utfsm.cl
Departamento de Informatica                     Fono: +56 32 654431
Universidad Tecnica Federico Santa Maria              +56 32 654239
Casilla 110-V, Valparaiso, Chile                Fax:  +56 32 797513
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