From: Glenn Morris <rgm@gnu.org>
Date: Tue, 21 Feb 2017 02:30:40 +0000 (-0800)
Subject: Ensure delayed-init custom variables get marked special
X-Git-Tag: emacs-26.0.90~751
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=96cea19842b577eb4f2e057d702aea54d736233e;p=emacs.git

Ensure delayed-init custom variables get marked special

* lisp/custom.el (custom-reevaluate-setting):
If the variable has never been set, defvar it.  (Bug#25770)
---

diff --git a/lisp/custom.el b/lisp/custom.el
index 70b6839db3d..7eaff450c5d 100644
--- a/lisp/custom.el
+++ b/lisp/custom.el
@@ -764,9 +764,17 @@ Return non-nil if the `customized-value' property actually changed."
 Use the :set function to do so.  This is useful for customizable options
 that are defined before their standard value can really be computed.
 E.g. dumped variables whose default depends on run-time information."
-  (funcall (or (get symbol 'custom-set) 'set-default)
-	   symbol
-	   (eval (car (or (get symbol 'saved-value) (get symbol 'standard-value))))))
+  (let ((val (car (or (get symbol 'saved-value)
+		      (get symbol 'standard-value)))))
+    (if (default-boundp symbol)
+	(funcall (or (get symbol 'custom-set) 'set-default) symbol (eval val))
+      ;; If it has never been set at all, defvar it so as to mark it
+      ;; special, etc (bug#25770).  This ignores any :set function,
+      ;; but that is not supposed to be used for initialization anyway.
+      ;; Or we could move this branch to the start, then unconditionally
+      ;; call the custom-set branch.
+      (eval `(defvar ,symbol ,val)))))
+
 
 
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