LOBOTOMY, and the (maybe found?) BIGNUM BUG

[JONL at MIT-MC (Jon L White)]

The bignum bug you reported the other day is a quotient
which seems to exercise some code in the BIGNUM package
at BQC1:, and I don't see why that code is there;  happily,
if I flush the code, there is no bug in your division.
So I'm rather blindly flushing it, and have run many minutes of
random bignum divisions to see that almost no other cases
exercise this code.  The hairy cases found by RWG and noted
in the source listing don't enter in here.  Possibly only
divisions where the quotient is equal to a number of the
form  1+2^N  for N > 36., will exercise this code, and
in all cases I've inspected, the removal of the (buggy)
code seems to be the right thing to do.  I've patched
this in to lisp and xlisp.