--- hello	80ad86578e12a12c838cd4ff7ca226aa6bcc44e9
+++ hello	94ebfe438b30bf18631c1846b2891b818f46aa23
@@ -9,3 +9,9 @@ int main()
 {
         say_hello();
 }
+
+void say_goodbye()
+{
+        printf("goodbye\n");
+}
+