APPEND etags--xref-backend to xref-backend-functions

* lisp/progmodes/xref.el (xref-backend-functions):
Use APPEND when adding the default element
(http://lists.gnu.org/archive/html/emacs-devel/2015-12/msg00061.html).

diff --git a/lisp/progmodes/xref.el b/lisp/progmodes/xref.el
index 8a69b07132e10ceb599d1517c6de0ddc6cbb7144..397f379d43443a9f8184a5dc495d618bdf5cfb7f 100644 (file)
--- a/lisp/progmodes/xref.el
+++ b/lisp/progmodes/xref.el
@@ -209,8 +209,9 @@ or an xref backend, which is a value to be used to dispatch the
 generic functions.")
 
 ;; We make the etags backend the default for now, until something
-;; better comes along.
-(add-hook 'xref-backend-functions #'etags--xref-backend)
+;; better comes along.  Use APPEND so that any `add-hook' calls made
+;; before this package is loaded put new items before this one.
+(add-hook 'xref-backend-functions #'etags--xref-backend t)
 
 ;;;###autoload
 (defun xref-find-backend ()