* eieio-core.el (eieio--full-class-object): New function.

Rather than explicitly call eieio-class-un-autoload, the autoloading is
now performed on-demand if you use eieio--full-class-object.

* lisp/emacs-lisp/eieio-core.el (eieio-class-un-autoload): Remove.
(eieio--full-class-object): New function, to replace it.
(eieio-oref, eieio--class-precedence-list):
* lisp/emacs-lisp/eieio-base.el (eieio-persistent-convert-list-to-object):
Use it instead of eieio-class-un-autoload.
* lisp/emacs-lisp/eieio.el (eieio-class-parents, child-of-class-p):
Load the class if needed.

lisp/emacs-lisp/eieio-base.el

@@ -277,8 +277,7 @@ identified, and needing more object creation."
 	  (progn
 	    ;; If OBJCLASS is an eieio autoload object, then we need to
 	    ;; load it.
-	    (eieio-class-un-autoload objclass)
-	    (eieio--class-object objclass))))
+	    (eieio--full-class-object objclass))))
 
     (while slots
       (let ((initarg (car slots))

lisp/emacs-lisp/eieio-core.el

@@ -125,7 +125,8 @@ Currently under control of this var:
 (defsubst eieio--class-object (class)
   "Return the class object."
   (if (symbolp class)
-      ;; Keep the symbol if class-v is nil, for better error messages.
+      ;; Return the symbol if the class object doesn't exist,
+      ;; for better error messages.
       (or (cl--find-class class) class)
     class))
 
@@ -217,10 +218,6 @@ It creates an autoload function for CNAME's constructor."
         (make-obsolete-variable cname (format "use \\='%s instead" cname)
                                 "25.1"))
 
-      ;; Store the new class vector definition into the symbol.  We need to
-      ;; do this first so that we can call defmethod for the accessor.
-      ;; The vector will be updated by the following while loop and will not
-      ;; need to be stored a second time.
       (setf (cl--find-class cname) newc)
 
       ;; Create an autoload on top of our constructor function.
@@ -230,9 +227,17 @@ It creates an autoload function for CNAME's constructor."
         (autoload (intern (format "%s-child-p" cname)) filename "" nil nil)
         (autoload (intern (format "%s-list-p" cname)) filename "" nil nil)))))
 
-(defsubst eieio-class-un-autoload (cname)
-  "If class CNAME is in an autoload state, load its file."
-  (autoload-do-load (symbol-function cname))) ; cname
+(defun eieio--full-class-object (class)
+  "Like `eieio--class-object' but loads the class if needed."
+  (let ((c (eieio--class-object class)))
+    (and (not (symbolp c))
+         ;; If the default-object-cache slot is nil, the class object
+         ;; is still a "dummy" setup by eieio-defclass-autoload.
+         (not (eieio--class-default-object-cache c))
+         ;; FIXME: We rely on the autoload setup for the "standard"
+         ;; constructor, here!
+         (autoload-do-load (symbol-function (eieio--class-name c))))
+    c))
 
 (cl-deftype list-of (elem-type)
   `(and list
@@ -730,9 +735,7 @@ Argument FN is the function calling this verifier."
   (cl-check-type obj (or eieio-object class))
   (let* ((class (cond ((symbolp obj)
                        (error "eieio-oref called on a class: %s" obj)
-                       (let ((c (cl--find-class obj)))
-                         (if (eieio--class-p c) (eieio-class-un-autoload obj))
-                         c))
+                       (eieio--full-class-object obj))
                       (t (eieio--object-class obj))))
 	 (c (eieio--slot-name-index class slot)))
     (if (not c)
@@ -1013,16 +1016,15 @@ The order, in which the parents are returned depends on the
 method invocation orders of the involved classes."
   (if (or (null class) (eq class eieio-default-superclass))
       nil
-    (unless (eieio--class-default-object-cache class)
-      (eieio-class-un-autoload (eieio--class-name class)))
-    (cl-case (eieio--class-method-invocation-order class)
-      (:depth-first
-       (eieio--class-precedence-dfs class))
-      (:breadth-first
-       (eieio--class-precedence-bfs class))
-      (:c3
-       (eieio--class-precedence-c3 class))))
-  )
+    (let ((class (eieio--full-class-object class)))
+      (cl-case (eieio--class-method-invocation-order class)
+        (:depth-first
+         (eieio--class-precedence-dfs class))
+        (:breadth-first
+         (eieio--class-precedence-bfs class))
+        (:c3
+         (eieio--class-precedence-c3 class))))))
+
 (define-obsolete-function-alias
   'class-precedence-list 'eieio--class-precedence-list "24.4")
 

lisp/emacs-lisp/eieio.el

@@ -425,10 +425,11 @@ If EXTRA, include that in the string returned to represent the symbol."
   'object-class-name 'eieio-object-class-name "24.4")
 
 (defun eieio-class-parents (class)
+  ;; FIXME: What does "(overload of variable)" mean here?
   "Return parent classes to CLASS.  (overload of variable).
 
 The CLOS function `class-direct-superclasses' is aliased to this function."
-  (eieio--class-parents (eieio--class-object class)))
+  (eieio--class-parents (eieio--full-class-object class)))
 
 (define-obsolete-function-alias 'class-parents #'eieio-class-parents "24.4")
 
@@ -468,7 +469,7 @@ The CLOS function `class-direct-subclasses' is aliased to this function."
 
 (defun child-of-class-p (child class)
   "Return non-nil if CHILD class is a subclass of CLASS."
-  (setq child (eieio--class-object child))
+  (setq child (eieio--full-class-object child))
   (cl-check-type child eieio--class)
   ;; `eieio-default-superclass' is never mentioned in eieio--class-parents,
   ;; so we have to special case it here.