- (let ((name (function-name-core
- (generic-function-name func))))
- (when (or (not (eq (symbol-package name) package))
- (gethash name externs))
+ (multiple-value-bind (name knownp)
+ (function-name-core (generic-function-name func))
+ (when (and knownp
+ (or (not (eq (symbol-package name) package))
+ (gethash name externs)))