bug#25556: 26.0.50.1; Requiring uncompiled eieio issues obsoletion warnings

[npostavs]

David Engster <deng@randomsample.de> writes:

> Eli Zaretskii writes:
>>> From: David Engster <deng@randomsample.de>
>>> Date: Fri, 27 Jan 2017 21:38:58 +0100
>>> 
>>
>>> I'm currently trying to fix compiler warnings during the CEDET compile
>>> in Emacs master, but there's one annoying problem I'm unsure how to
>>> fix. Whenever a file does (require 'eieio), and EIEIO is not yet
>>> byte-compiled, those two warnings are issued:
>>> 
>>> ../../emacs-lisp/eieio.el: ‘eieio-object-name-string’ is an obsolete
>>> generic function (as of 25.1); use ‘eieio-named’ instead.
>>> ../../emacs-lisp/eieio.el: ‘destructor’ is an obsolete generic
>>> function (as of 26.1).
>>> 
>>> Since EIEIO is compiled pretty late, one is flooded with these warnings
>>> when compiling Emacs master. The warnings seems to come from the
>>> cl-defgeneric for `eieio-object-name-string' and `destructor'. How can
>>> this be dealt with?
>>
>> Is it possibel to arrange that these files be compiled sooner?  We
>> already have some targets for similar purposes in lisp/Makefile.
>
> I'm sure that's possible, but why does the file that declares those
> constructs obsolete *itself* throw these warnings? I was hoping that
> this could be fixed instead.

I'm not sure about `eieio-object-name-string', but the message about
`destructor' is because cl-defgeneric makes the declaration handling
code run before the function defining code, so the symbol is declared
obsolete before it's defined and the definition itself triggers the
obsolete warning.  The patch below moves it around and stops the
`destructor' warning:

--- i/lisp/emacs-lisp/cl-generic.el
+++ w/lisp/emacs-lisp/cl-generic.el
@@ -226,7 +226,13 @@ cl-defgeneric
     (when (eq 'setf (car-safe name))
       (require 'gv)
       (setq name (gv-setter (cadr name))))
-    `(progn
+    `(prog1
+         (progn
+           (defalias ',name
+             (cl-generic-define ',name ',args ',(nreverse options))
+             ,(help-add-fundoc-usage doc args))
+           ,@(mapcar (lambda (method) `(cl-defmethod ,name ,@method))
+                     (nreverse methods)))
        ,@(mapcar (lambda (declaration)
                    (let ((f (cdr (assq (car declaration)
                                        defun-declarations-alist))))
@@ -235,12 +241,7 @@ cl-defgeneric
                       (t (message "Warning: Unknown defun property `%S' in %S"
                                   (car declaration) name)
                          nil))))
-                 (cdr declarations))
-       (defalias ',name
-         (cl-generic-define ',name ',args ',(nreverse options))
-         ,(help-add-fundoc-usage doc args))
-       ,@(mapcar (lambda (method) `(cl-defmethod ,name ,@method))
-                 (nreverse methods)))))
+                 (cdr declarations)))))
 
 ;;;###autoload
 (defun cl-generic-define (name args options)