0.8.3.61:

0.8.3.61:
	Fix for compiler "cannot convert to SINGLE-FLOAT: <largenum>" in
	type inference, as reported PFD sbcl-devel 2003-09-13:
	... a slight rewrite to the SIGNED-ZERO-OP methods in
		src/compiler/srctran.lisp
	... not correct in the presence of one integer and one float argument,
		as coercion could still occur.  Break me if you can.