diff --git a/src/ast/datatype_decl_plugin2.h b/src/ast/datatype_decl_plugin2.h
index f076bb43f..d9bfea4a5 100644
--- a/src/ast/datatype_decl_plugin2.h
+++ b/src/ast/datatype_decl_plugin2.h
@@ -429,4 +429,4 @@ inline void del_datatype_decls(unsigned num, datatype_decl * const * ds) {}
 
 #endif /* DATATYPE_DECL_PLUGIN_H_ */
 
-#endif DATATYPE_V2
+#endif /* DATATYPE_V2 */