diff --git a/data/c.m4 b/data/c.m4
index e28954be..2a3218bf 100644
--- a/data/c.m4
+++ b/data/c.m4
@@ -53,6 +53,9 @@ m4_define([b4_identification],
 [/* Identify Bison output.  */
 [#]define YYBISON 1
 
+/* Bison version.  */
+[#]define YYBISON_VERSION "b4_version"
+
 /* Skeleton name.  */
 [#]define YYSKELETON_NAME b4_skeleton