case:
MKBFD If set to "no", disables building of libbfd, libiberty,
and all things that depend on them (binutils/gas/ld, gdb,
dbsym, mdsetimage).
MKGDB If set to "no", disables bulding of gdb.
MKGCC If set to "no", disables building of gcc and the
gcc-related libraries (libg2c, libgcc, libobjc, libstdc++).
These are useful for building platforms for which either of the following
situations are true:
(1) You have no userland from which to run toolchain2netbsd
in order to build the appropriate toolchain build framework.
(2) The platform which you are building requires a newer set
of tools than are currently in the tree (e.g. x86-64, ia64).
* Rewrite src/tools Make logic to work like the rest of the tree wrt
"dependall" and "install". The old "make build" hack is gone.
* Remove the MKTOOLS logic. This was linked to the "make build" hack,
and was only needed because TOOLDIR originally had no writable default.
* Redo the GNU configure/make logic to make it fit reasonably in a
BSD make wrapper. Use new ${.ALLTARGETS} variable to scan for
targets in $(srcdir), and mark them with .MADE: to prevent rebuilding.
* Only build cross tools in src/tools; remove some messy logic in
src/usr.* and src/gnu/usr.* that would do target filename rewriting
(improves consistency and readability).
* Add the ability to build cross gdb at tool build time by setting
MKCROSSGDB (default no) to "yes" in mk.conf.
* Add src/tools/groff and set up paths to work with this cross groff.