From: Glenn Morris <rgm@gnu.org>
Date: Tue, 13 Dec 2016 01:03:20 +0000 (-0500)
Subject: Minor fix for define-derived-mode
X-Git-Tag: emacs-26.0.90~1117
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=8db7b65d66f01e90a05cc9f11c67667233d84ca0;p=emacs.git

Minor fix for define-derived-mode

* lisp/emacs-lisp/derived.el (define-derived-mode):
Do not let eg eval-defun reset the values of syntax or abbrev tables,
since they might have been defined externally.  (Bug#16160)
---

diff --git a/lisp/emacs-lisp/derived.el b/lisp/emacs-lisp/derived.el
index 0f7691af0f4..31170270f5c 100644
--- a/lisp/emacs-lisp/derived.el
+++ b/lisp/emacs-lisp/derived.el
@@ -217,16 +217,17 @@ No problems result if this variable is not bound.
        ,(if declare-syntax
 	    `(progn
 	       (unless (boundp ',syntax)
-		 (put ',syntax 'definition-name ',child))
-	       (defvar ,syntax (make-syntax-table))
+		 (put ',syntax 'definition-name ',child)
+		 (defvar ,syntax (make-syntax-table)))
 	       (unless (get ',syntax 'variable-documentation)
 		 (put ',syntax 'variable-documentation
 		      (purecopy ,(format "Syntax table for `%s'." child))))))
        ,(if declare-abbrev
 	    `(progn
-	       (put ',abbrev 'definition-name ',child)
-	       (defvar ,abbrev
-		 (progn (define-abbrev-table ',abbrev nil) ,abbrev))
+	       (unless (boundp ',abbrev)
+		 (put ',abbrev 'definition-name ',child)
+		 (defvar ,abbrev
+		   (progn (define-abbrev-table ',abbrev nil) ,abbrev)))
 	       (unless (get ',abbrev 'variable-documentation)
 		 (put ',abbrev 'variable-documentation
 		      (purecopy ,(format "Abbrev table for `%s'." child))))))