AMD64-patch for buildworld

[Matthew Dillon]

:Matt,
:
:can you give more details of varsyms for building 32 and 64 bit world
:in the same place?   it is not a time to worry about it, but it is a
:time that i should know this :).
:
:Thanks
:YYH

    What I envision is to have our standard buildworld/installworld
    system install binaries into e.g. /bin.i386 instead /bin.  A 64 bit
    build would install into /bin.amd64 instead of /bin.  "/bin" itself
    would then by a varsym that looks like this:  "/bin.${MACHINE}", and
    of course that variable would automatically be initialized by the
    kernel.

    Other locations in the kernel containing libraries and binaries, as
    well as the compiler libraries and binaries, would also use varsyms.

    Ultimately I want an installed world to be able to operate in a mixed
    mode, both 32 and 64 bits at the same time.  The kernel itself would
    of course be a 64 bit kernel with two system call tables (one for 32 bit
    mode, one for 64 bit mode).  Thew 32 bit table would translate system
    calls to native 64 bit operation.

    This is kind of an ultimate goal, don't let it intefere with all the
    primary work of just getting 64 bit working in the first place!

						-Matt