+ (let ((old-function-info (info :function :info name)))
+ (when old-function-info
+ ;; This is handled as an error because it's generally a bad
+ ;; thing to blow away all the old optimization stuff. It's
+ ;; also a potential source of sneaky bugs:
+ ;; DEFKNOWN FOO
+ ;; DEFTRANSFORM FOO
+ ;; DEFKNOWN FOO ; possibly hidden inside some macroexpansion
+ ;; ; Now the DEFTRANSFORM doesn't exist in the target Lisp.
+ ;; However, it's continuable because it might be useful to do
+ ;; it when testing new optimization stuff interactively.
+ (cerror "Go ahead, overwrite it."
+ "~@<overwriting old FUNCTION-INFO ~2I~_~S ~I~_for ~S~:>"
+ old-function-info name)))