1 files changed, 1 insertions, 1 deletions

diff --git a/lisp/files.el b/lisp/files.el
index 1c3c93878cc..f6c0b5e9728 100644
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -842,7 +842,7 @@ run `normal-mode' explicitly."
                                   ("\\.p\\'" . pascal-mode)
                                   ("\\.pas\\'" . pascal-mode)
                                   ("\\.mss\\'" . scribe-mode)
-                                  ("\\.ada\\'" . ada-mode)
+                                  ("\\.ad[abs]\\'" . ada-mode)
                                   ("\\.icn\\'" . icon-mode)
                                   ("\\.pl\\'" . prolog-mode)
                                   ("\\.cc\\'" . c++-mode)