From 9993b5610cd7c82669de43fbad0bc3d022450b77 Mon Sep 17 00:00:00 2001
From: "Richard M. Stallman" <rms@gnu.org>
Date: Mon, 30 Oct 1995 19:25:04 +0000
Subject: [PATCH] (select-tags-table): Don't modify the value of
 tags-table-list.

---
 lisp/progmodes/etags.el | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lisp/progmodes/etags.el b/lisp/progmodes/etags.el
index 8650a995dd4..2b4a876e494 100644
--- a/lisp/progmodes/etags.el
+++ b/lisp/progmodes/etags.el
@@ -1461,7 +1461,7 @@ see the doc of that variable if you want to add names to the list."
 	  (prin1 tags-file-name (current-buffer)) ;invisible
 	  (insert "\n")))
     (setq set-list (delete tags-file-name
-			   (apply 'nconc (cons tags-table-list
+			   (apply 'nconc (cons (copy-sequence tags-table-list)
 					       (mapcar 'copy-sequence
 						       tags-table-set-list)))))
     (while set-list
-- 
2.39.2