diff --git a/Modules/sha512module.c b/Modules/sha512module.c
index 9f47b61..b62cfd9 100644
--- a/Modules/sha512module.c
+++ b/Modules/sha512module.c
@@ -602,8 +602,7 @@
 };
 
 static PyTypeObject SHA384type = {
-    PyObject_HEAD_INIT(NULL)
-    0,			/*ob_size*/
+    PyVarObject_HEAD_INIT(NULL, 0)
     "_sha512.sha384",	/*tp_name*/
     sizeof(SHAobject),	/*tp_size*/
     0,			/*tp_itemsize*/
@@ -637,8 +636,7 @@
 };
 
 static PyTypeObject SHA512type = {
-    PyObject_HEAD_INIT(NULL)
-    0,			/*ob_size*/
+    PyVarObject_HEAD_INIT(NULL, 0)
     "_sha512.sha512",	/*tp_name*/
     sizeof(SHAobject),	/*tp_size*/
     0,			/*tp_itemsize*/
@@ -755,10 +753,10 @@
 {
     PyObject *m;
 
-    SHA384type.ob_type = &PyType_Type;
+    Py_Type(&SHA384type) = &PyType_Type;
     if (PyType_Ready(&SHA384type) < 0)
         return;
-    SHA512type.ob_type = &PyType_Type;
+    Py_Type(&SHA512type) = &PyType_Type;
     if (PyType_Ready(&SHA512type) < 0)
         return;
     m = Py_InitModule("_sha512", SHA_functions);