[PATCH] __FreeBSD_kernel__

[Ed Maste]

On Sat, Jul 02, 2011 at 07:37:24PM -0400, Alexander Kabaev wrote:

> On Sat, 2 Jul 2011 17:41:03 +0200
> Robert Millan <rmh at debian.org> wrote:
> 
> > My request is that FreeBSD also defines __FreeBSD_kernel__.  If this
> > happens, life would be made a bit easier on both sides, as it'd be
> > more natural for porters of either system to support both using a
> > single macro [1].

I think this is a good idea, especially if it means that a single change can
make it into upstream projects to support both FreeBSD and Debian
kFreeBSD.

> I do not think this belongs in GCC at all. You should already have a
> defined symbol to identify your OS and that should be used in cases
> where it matters.

I suspect the proposed patch put it in GCC based on the fact that we
already have __FreeBSD__ in contrib/gcc/config/freebsd-spec.h:
        builtin_define_with_int_value ("__FreeBSD__", FBSD_MAJOR);      \       

> Alternatively, you should provide the symbol in
> similar way in which we provide __FreeBSD_version, through well-known
> header like sys/param.h and not pollute GCC.

I suspect this is probably a reasonable alternative, but may mean software
will have to pick up an additional #include.

Out of curiosity, what is the canonical way for software to identify a
Linux kernel -- __linux__ or some variant?  Where is it defined?

Regards,
Ed Maste