From 1e47f7492afbca15f5d1f3a76d797443b6553eb4 Mon Sep 17 00:00:00 2001
From: David Ponce <da_vid@orange.fr>
Date: Fri, 31 Oct 2025 13:34:46 -0400
Subject: [PATCH] lisp/emacs-lisp/cl-*.el: Minor changes accumulated during new
 API design

* lisp/emacs-lisp/cl-macs.el (cl-deftype): Support dispatch on
types that take arguments, as long as they can be used without arguments.

* lisp/emacs-lisp/cl-generic.el (cl--generic-derived-mode-specializers):
Rename from `cl--generic-derived-specializers` to clarify it's about
derived modes and not derived types.
(cl--generic-derived-mode-generalizer): Adjust accordingly and rename
from `cl--generic-derived-generalizer` for the same reason.
Ignore additional args in the tagcode function.
(cl-generic-generalizers) <derived-mode>: Adjust accordingly.

* lisp/emacs-lisp/macroexp.el (macroexp--dynamic-variable-p): Simplify.
---
 lisp/emacs-lisp/cl-generic.el | 12 ++++++------
 lisp/emacs-lisp/cl-macs.el    | 37 ++++++++++++++++++++++++++++++-----
 lisp/emacs-lisp/macroexp.el   |  1 -
 3 files changed, 38 insertions(+), 12 deletions(-)

diff --git a/lisp/emacs-lisp/cl-generic.el b/lisp/emacs-lisp/cl-generic.el
index 453a49e6609..ad032e82e9e 100644
--- a/lisp/emacs-lisp/cl-generic.el
+++ b/lisp/emacs-lisp/cl-generic.el
@@ -1047,7 +1047,7 @@ those methods.")
       ('cl--generic-eql-generalizer '(eql 'x))
       ('cl--generic-struct-generalizer 'cl--generic)
       ('cl--generic-typeof-generalizer 'integer)
-      ('cl--generic-derived-generalizer '(derived-mode c-mode))
+      ('cl--generic-derived-mode-generalizer '(derived-mode c-mode))
       ('cl--generic-oclosure-generalizer 'oclosure)
       (_ x))))
 
@@ -1466,19 +1466,19 @@ This currently works for built-in types and types built on top of records."
 ;;   "&context (major-mode c-mode)" rather than
 ;;   "&context (major-mode (derived-mode c-mode))".
 
-(defun cl--generic-derived-specializers (mode &rest _)
+(defun cl--generic-derived-mode-specializers (mode &rest _)
   ;; FIXME: Handle (derived-mode <mode1> ... <modeN>)
   (mapcar (lambda (mode) `(derived-mode ,mode))
           (derived-mode-all-parents mode)))
 
-(cl-generic-define-generalizer cl--generic-derived-generalizer
-  90 (lambda (name) `(and (symbolp ,name) (functionp ,name) ,name))
-  #'cl--generic-derived-specializers)
+(cl-generic-define-generalizer cl--generic-derived-mode-generalizer
+  90 (lambda (name &rest _) `(and (symbolp ,name) (functionp ,name) ,name))
+  #'cl--generic-derived-mode-specializers)
 
 (cl-defmethod cl-generic-generalizers ((_specializer (head derived-mode)))
   "Support for (derived-mode MODE) specializers.
 Used internally for the (major-mode MODE) context specializers."
-  (list cl--generic-derived-generalizer))
+  (list cl--generic-derived-mode-generalizer))
 
 (cl-generic-define-context-rewriter major-mode (mode &rest modes)
   `(major-mode ,(if (consp mode)
diff --git a/lisp/emacs-lisp/cl-macs.el b/lisp/emacs-lisp/cl-macs.el
index 2c2451e14cd..73b3b243643 100644
--- a/lisp/emacs-lisp/cl-macs.el
+++ b/lisp/emacs-lisp/cl-macs.el
@@ -3816,12 +3816,39 @@ If PARENTS is non-nil, ARGLIST must be nil."
       (cl-callf (lambda (x) (delq parent-decl x)) (cdr declares))
       (when (equal declares '(declare))
         (cl-callf (lambda (x) (delq declares x)) decls)))
-    (and parents arglist
-         (error "Parents specified, but arglist not empty"))
     (let* ((expander
-            `(cl-function (lambda (&cl-defs ('*) ,@arglist) ,@decls ,@forms)))
-           ;; FIXME: Pass a better lexical context.
-           (specifier (ignore-errors (funcall (eval expander t))))
+            `(cl-function
+              (lambda (&cl-defs ('*) ,@arglist) ,@decls ,@forms)))
+           (specifier
+            (condition-case nil
+                ;; FIXME: Pass a better lexical context.
+                (funcall (eval expander t))
+              ;; We previously signaled an error when the type specified
+              ;; both non-nil parents and arglist, like `unsigned-byte'
+              ;; in below example:
+              ;;
+              ;; (cl-deftype my-integer ()
+              ;;   'integer)
+              ;;
+              ;; (cl-deftype unsigned-byte (&optional bits)
+              ;;   "Unsigned integer."
+              ;;   (declare (parents my-integer))
+              ;;   `(integer 0 ,(if (memq bits '(nil *))
+              ;;                    bits
+              ;;                  (1- (ash 1 bits)))))
+              ;;
+              ;; In order to accept the above (correct) definition of
+              ;; `unsigned-byte', call the expander without arguments to
+              ;; check if the arglist is mandatory by catching a
+              ;; `wrong-number-of-arguments' error.  If so, and the type
+              ;; specified both parents and arglist, there is a good
+              ;; chance that the type is not atomic, so signal it;
+              ;; otherwise, return nil as previously.  Report any other
+              ;; error on type definition.
+              (wrong-number-of-arguments
+               (and parents arglist ;; type is not atomic
+                    (error "Type %S with parents may be not atomic: %S"
+                           name arglist)))))
            (predicate
             (pcase specifier
               (`(satisfies ,f) `#',f)
diff --git a/lisp/emacs-lisp/macroexp.el b/lisp/emacs-lisp/macroexp.el
index 2bf9e0eb451..e89ad4e17e4 100644
--- a/lisp/emacs-lisp/macroexp.el
+++ b/lisp/emacs-lisp/macroexp.el
@@ -399,7 +399,6 @@ change this."
 (defun macroexp--dynamic-variable-p (var)
   "Whether the variable VAR is dynamically scoped.
 Only valid during macro-expansion."
-  (defvar byte-compile-bound-variables)
   (or (not lexical-binding)
       (special-variable-p var)
       (memq var macroexp--dynvars)