(select-tags-table): Don't modify the value of tags-table-list.

diff --git a/lisp/progmodes/etags.el b/lisp/progmodes/etags.el
index 8650a995dd4d740627974b7b9c5f8a280d648c31..2b4a876e494303d498fc8992621537c46e190e79 100644 (file)
--- 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