From 171c7fd6df861ab71f6cc8faedb8ff68bfac4bae Mon Sep 17 00:00:00 2001
From: Stefan Monnier <monnier@iro.umontreal.ca>
Date: Tue, 14 Oct 2025 11:21:29 -0400
Subject: [PATCH] (define-minor-mode): Update `global-minor-modes` if
 init-value is non-nil

When a global minor mode is enabled by init-value rather than by
calling the major mode function, we failed to register it in
`global-minor-modes` (bug#79518).

* lisp/emacs-lisp/easy-mmode.el (define-minor-mode): Register
ourselves in `global-minor-modes` at top-level for global modes
with a non-nil init-value.
Also in the `modefun`, simply the code with `not` and `add-to-list`
and consolidate the local/global paths to update `*-minor-modes`.

* lisp/simple.el (global-minor-modes): Move to...
* lisp/subr.el (global-minor-modes): ...here so it's defined early enough
for `auto-compression-mode` to register itself.
---
 lisp/emacs-lisp/easy-mmode.el | 53 ++++++++++++++++-------------------
 lisp/simple.el                |  4 ---
 lisp/subr.el                  |  4 +++
 3 files changed, 28 insertions(+), 33 deletions(-)

diff --git a/lisp/emacs-lisp/easy-mmode.el b/lisp/emacs-lisp/easy-mmode.el
index 25e4f882295..0aa1fe2ce9d 100644
--- a/lisp/emacs-lisp/easy-mmode.el
+++ b/lisp/emacs-lisp/easy-mmode.el
@@ -332,12 +332,16 @@ for a description of this minor mode."
 Setting this variable directly does not take effect;
 either customize it (see the info node `Easy Customization')
 or call the function `%s'."))))
-	    `(defcustom ,mode ,init-value
-	       ,(format base-doc-string pretty-name mode mode)
-	       ,@set
-	       ,@initialize
-	       ,@type
-               ,@(nreverse extra-keywords)))))
+	    `(progn
+	       (defcustom ,mode ,init-value
+	         ,(format base-doc-string pretty-name mode mode)
+	         ,@set
+	         ,@initialize
+	         ,@type
+	         ,@(nreverse extra-keywords))
+	       ,(when init-value
+	          `(when (bound-and-true-p ,mode)
+                     (add-to-list 'global-minor-modes ',modefun)))))))
 
        ;; The actual function.
        ,(funcall
@@ -360,30 +364,21 @@ or call the function `%s'."))))
                            'toggle)))))
 	    (let ((,last-message (current-message)))
               (,@setter
-               (cond ((eq arg 'toggle)
-                      (not ,getter))
-                     ((and (numberp arg)
-                           (< arg 1))
-                      nil)
-                     (t
-                      t)))
+               (cond ((eq arg 'toggle) (not ,getter))
+                     (t (not (and (numberp arg) (< arg 1))))))
               ;; Keep minor modes list up to date.
-              ,@(if globalp
-                    ;; When running this byte-compiled code in earlier
-                    ;; Emacs versions, these variables may not be defined
-                    ;; there.  So check defensively, even if they're
-                    ;; always defined in Emacs 28 and up.
-                    `((when (boundp 'global-minor-modes)
-                        (setq global-minor-modes
-                              (delq ',modefun global-minor-modes))
-                        (when ,getter
-                          (push ',modefun global-minor-modes))))
-                  ;; Ditto check.
-                  `((when (boundp 'local-minor-modes)
-                      (setq local-minor-modes
-                            (delq ',modefun local-minor-modes))
-                      (when ,getter
-                        (push ',modefun local-minor-modes)))))
+              ,(let ((minor-modes-var (if globalp
+                                          'global-minor-modes
+                                        'local-minor-modes)))
+                 ;; When running this byte-compiled code in earlier
+                 ;; Emacs versions, these variables may not be defined
+                 ;; there.  So check defensively, even if they're
+                 ;; always defined in Emacs 28 and up.
+                 `(when (boundp ',minor-modes-var)
+                    (if ,getter
+                        (add-to-list ',minor-modes-var ',modefun)
+                      (setq ,minor-modes-var
+                            (delq ',modefun ,minor-modes-var)))))
               ,@body
               ;; The on/off hooks are here for backward compatibility only.
               (run-hooks ',hook (if ,getter ',hook-on ',hook-off))
diff --git a/lisp/simple.el b/lisp/simple.el
index 824f7c5a1a0..589b136a008 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -157,10 +157,6 @@ messages are highlighted; this helps to see what messages were visited."
   nil
   "Overlay highlighting the current error message in the `next-error' buffer.")
 
-(defvar global-minor-modes nil
-  "A list of the currently enabled global minor modes.
-This is a list of symbols.")
-
 (defcustom next-error-hook nil
   "List of hook functions run by `next-error' after visiting source file."
   :type 'hook
diff --git a/lisp/subr.el b/lisp/subr.el
index 9f1680f3896..891663f7640 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -3064,6 +3064,10 @@ though trying to avoid AVOIDED-MODES."
                                          hs-minor-mode)
   "List of all minor mode functions.")
 
+(defvar global-minor-modes nil
+  "A list of the currently enabled global minor modes.
+This is a list of symbols.")
+
 (defun add-minor-mode (toggle name &optional keymap after toggle-fun)
   "Register a new minor mode.