platform/pc64 will be dropped

[Matthew Dillon]

    Guys guys, don't get ahead of yourselves.  I investigated this a while
    ago and while there are many bits which are similar, they are not anywhere
    near the same.

    There are major assumptions with regards to whether variables are 32 bits
    or 64 bits wide.  The one thing we *CANNOT* afford to do is to start
    screwing around with the pc32 code to make it compatible with pc64.  The
    pc64 work has to be able to progress without any chance of it interfering
    with the 32 bit code.

    Certainly there are bits in pc32 that could be made machine-independant.
    Originally there was a ton of MI code in pc32, inherited from the FreeBSD
    tree, and while I've moved some of it out I haven't gotten all of it.

    Similarly, some bits of pc32 can be moved to the cpu hierarchy... but
    ONLY those bits that are also needed by the virtual kernel (otherwise
    they ARE platform and not cpu specific bits and have to stay in pc32).

    There will be some near duplication of code but the purpose of having
    pc64 is to provide a place where work can progress without causing the
    pc32 builds to start failing and crashing.

						-Matt