Index: /trunk/source/lib/defstruct.lisp
===================================================================
--- /trunk/source/lib/defstruct.lisp	(revision 13343)
+++ /trunk/source/lib/defstruct.lisp	(revision 13344)
@@ -285,6 +285,10 @@
           (when def (set-function-info refname nil)))
         (when (symbolp refname)(fmakunbound refname)))
+      #|
+      ;; The print-function may indeed have become obsolete,
+      ;; but we can't generally remove user-defined code
       (let ((print-fn (sd-print-function sd)))
         (when (symbolp print-fn) (fmakunbound print-fn)))
+      |#
       (let ((constructor (sd-constructor sd)))
         (when (symbolp constructor) (fmakunbound constructor)))