diff --git a/Modules/unicodedata.c b/Modules/unicodedata.c
index a11a0b70b7c..a30d30c8eb7 100644
--- a/Modules/unicodedata.c
+++ b/Modules/unicodedata.c
@@ -75,7 +75,7 @@ static PyMemberDef DB_members[] = {
         {NULL}
 };
 
-// forward declaration
+/* forward declaration */
 static PyTypeObject UCD_Type;
 
 static PyObject*