> Now: how does your cross-compiler find its headers? If it takes
> _anything_ from /usr/include then it's going to have problems. We
> should be compiling with "-nostdinc -I$(BSDSRCDIR)/xinclude" and
> have 'make includes' install into $(BSDSRCDIR)/xinclude.
> $(DESTDIR)/usr/include should get updated at 'make install' time,
> not 'make includes' time.

I don't think it should be $(BSDSRCDIR); rather, I think it should
be $(DESTDIR)/include, or a variant thereof (?).  I think that would
ease compilation of binaries for multiple separate machine
architectures from the same source tree, and would allow you to do
that without modifying the source tree.  But the really hard part is
of course to get the cross compile environment (compiler and tools)
working properly.

- H=E5vard