*ARRAY doesn't check size for plausibility

[Robert W. Kerns <RWK at MIT-MC>]

It would be nice if (*ARRAY () T 100000. 12.) would give you an error,
instead of returning you an array that claims to be bigger than your
address space, but which only GC-protects a fraction of your address
space.  Even better, of course, would be to fix it so it really does
give you an array as big as it says it does.  Of course, we can always
simulate arrays by counting on our fingers.