In message: <20090909010833.ga12...@netbsd.org>
David Holland <dholland-sourcechan...@netbsd.org> writes:
: On Tue, Sep 08, 2009 at 10:02:33AM -0600, M. Warner Losh wrote:
: > __NetBSD__ is the *COMPILER* environment. Depending on it is *BAD*.
: > You need to use a different symbol. This is a bug in the NetBSD code
: > now. __NetBSD__ isn't, and never has bene, the KERNEL.
:
: No need to shout...
:
: Anyway, what does the compiler environment *mean* besides "we're
: building a NetBSD binary"? That's exactly what rumpkernel is, even if
: it's compiled with the FreeBSD compiler. Properly speaking it ought to
: be built with a cross-compiler; maybe that'll happen in the long term.
If you are building with a FreeBSD compiler, you are building a
FreeBSD binary, by definition. __FreeBSD__ means you are building a
FreeBSD binary. If that's not what you want to do, you need to jump
through a lot of hoops, but it usually easier to build a cross
compiler than jump through those hoops. There's a lot more to the
environment than just -D__FreeBSD__, there's the default binaries that
are produced, there's a bunch of defines and arch assertions, default
paths to includes and libraries, etc.
This may be inconvenient. I know years ago I tried building a NetBSD
kernel with a FreeBSD compiler, and that failed due to these
differences (and others other than __NetBSD__ not being defined).
Trying to kludge it caused me much pain and suffering. I abandoned
the effort because building a proper cross compiler turned out to be a
lot easier...
sorry for the shouting earlier, but this is a hot-button since I've
had to explain this difference many times to many people over the
years...
Warner
