-;;; Note: Technically there could be an ENV optional argument to SETF
-;;; MACRO-FUNCTION, but since ANSI says that the consequences of
-;;; supplying that optional argument are undefined, we don't allow it.
-;;; (Thus our implementation of this unspecified behavior is to
-;;; complain that the wrong number of arguments was supplied. Since
-;;; the behavior is unspecified, this is conforming.:-)
-(defun (setf sb!xc:macro-function) (function symbol)