diff --git a/Python/marshal.c b/Python/marshal.c
index ec6b3da..8d441a4 100644
--- a/Python/marshal.c
+++ b/Python/marshal.c
@@ -1696,7 +1696,7 @@
     if (!PyBytes_Check(data)) {
         PyErr_Format(PyExc_TypeError,
                      "file.read() returned not bytes but %.100s",
-                     data->ob_type->tp_name);
+                     Py_TYPE(data)->tp_name);
         result = NULL;
     }
     else {