Re: [patch 1/1] consolidate TRUE and FALSE

[Nicholas Miell]

On Thu, 2006-03-16 at 02:42 -0800, Andrew Morton wrote:
> Anton Altaparmakov <aia21@xxxxxxxxx> wrote:
> >
> > > Various places are doing things like
> >  > 
> >  > typedef {
> >  > 	FALSE,
> >  > 	TRUE
> >  > } my_fave_name_for_a_bool;
> >  > 
> >  > These are converted to
> >  > 
> >  > typedef int my_fave_name_for_a_bool;
> > 
> >  Given that the kernel now requires gcc 3.2 or later, that already includes 
> >  a native boolean type (_Bool)?
> 
> It does?
> 
> Is it any good?
> 
> bix:/home/akpm> cat t.c
> void foo()
> {
> 	_Bool b = 1;
> 
> 	b += 2;
> }
> bix:/home/akpm> gcc -O -Wall -c t.c
> bix:/home/akpm> 
> 
> Sigh.
> 

If you were to read the value of b after "b += 2", you'd find that b is
still 1.

Also note that _Bool is a byte, so anything that exposed its own custom
boolean type to userspace needs to be carefully updated.

-- 
Nicholas Miell <nmiell@xxxxxxxxxxx>

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