diff --git a/games/caesar/caesar.c b/games/caesar/caesar.c
index bc3af27d6702..da0a43770da6 100644
--- a/games/caesar/caesar.c
+++ b/games/caesar/caesar.c
@@ -80,7 +80,7 @@ double stdf[26] = {
 	2.62, 0.81, 1.88, 0.23,  2.07, 0.06,
 };
 
-void printit();
+void printit __P((char *));
 
 int
 main(argc, argv)