1 files changed, 2 insertions, 2 deletions

diff --git a/lisp/progmodes/cc-fonts.el b/lisp/progmodes/cc-fonts.el
index 087e71a1f11..698f83e0bd0 100644
--- a/lisp/progmodes/cc-fonts.el
+++ b/lisp/progmodes/cc-fonts.el
@@ -394,14 +394,14 @@ stuff.  Used on level 1 and higher."
             `(;; The stuff after #error and #warning is a message, so
               ;; fontify it as a string.
               ,@(when (c-lang-const c-cpp-message-directives)
-                  (let* ((re (c-make-keywords-re nil
+                  (let* ((re (c-make-keywords-re 'appendable ; nil
                                (c-lang-const c-cpp-message-directives)))
                          (re-depth (regexp-opt-depth re)))
                     `((,(concat noncontinued-line-end
                                 (c-lang-const c-opt-cpp-prefix)
                                 re
                                 "\\s +\\(.*\\)$")
-                       ,(+ ncle-depth re-depth 1) font-lock-string-face))))
+                       ,(+ ncle-depth re-depth 1) font-lock-string-face t))))
 
               ;; Fontify filenames in #include <...> as strings.
               ,@(when (c-lang-const c-cpp-include-directives)