Use of bool / stdbool.h in kernel

[John Baldwin]

On Wednesday, November 30, 2011 12:13:53 am Bruce Evans wrote:
> On Tue, 29 Nov 2011 mdf at freebsd.org wrote:
> 
> > At $WORK we have a hack in one of the *.mk files to allow including
> > stdbool.h in the kernel and we use it extensively.  This is not
> > allowed by style(9), as far as I can tell, because the file is in
> > include/stdbool.h and those files are not allowed to be included in
> > kernel sources.
> 
> Including stdbool.h in the kernel is not a style bug, but unsupported.
> 
> > What I want to check on is, would it be acceptable to move stdbool.h
> > from include/stdbool.h to sys/sys/stdbool.h (i.e. like errno.h) and
> > then include it in the kernel as <sys/stdbool.h>?  That is, is the
> 
> Would be a larger style bug, especially if it were actually used.
> Even its spellings of TRUE and FALSE are strange.  Even in userland
> stdbool.h is considered so useful that it is never used in src/bin
> and is only used a few times on other src/*bin.  src/bin never uses
> TRUE of FALSE either.

I suspect there is some bias here though due to the fact that there wasn't
a standard bool type when most of this code was written. :)  I don't think
that means we have to forgo use of the new type now that it is in fact
standardized in C99.  I would be happy to have 'bool' available and the
lowercase 'true' and 'false' are fine with me.

-- 
John Baldwin