two variables:
TOOLCHAIN_MISSING -- set to "yes" on platforms for which there is
no working in-tree toolchain (hppa, ns32k, sh5, x86_64).
EXTERNAL_TOOLCHAIN -- if defined by the user, points to the root of
an external toolchain (e.g. /usr/local/gnu). This enables the cross-build
framework even for TOOLCHAIN_MISSING platforms.
If TOOLCHAIN_MISSING is set to "yes", MKGDB, MKBFD, and MKGCC are all
unconditionally set to "no", since the bits are not there to build.
If EXTERNAL_TOOLCHAIN is set, MKGCC is unconditionally set to "no",
since the external toolchain's compiler is not in-sync with the
in-tree compiler support components (e.g. libgcc).
* Set MACHINE_CPU much earlier in bsd.own.mk, so that more tests in
that file can use it.
compiles. Based loosely on mkdep.old.compiler (so CSRG license copied),
but now uses just one rewrite (awk) process per cpp invocation and
determines the proper way to run cpp and awk via a "configure" script.
Use HOST_MKDEP in bsd.hostlib/hostprog.mk (defaulting to the old override
value of MKDEP), and give it a TOOLDIR equivalent in bsd.own.mk.
thorpej