diff --git a/Modules/gcmodule.c b/Modules/gcmodule.c
index 6c5011c..b6a871b 100644
--- a/Modules/gcmodule.c
+++ b/Modules/gcmodule.c
@@ -239,7 +239,7 @@
 	PyGC_Head *gc = containers->gc.gc_next;
 	for (; gc != containers; gc = gc->gc.gc_next) {
 		assert(gc->gc.gc_refs == GC_REACHABLE);
-		gc->gc.gc_refs = FROM_GC(gc)->ob_refcnt;
+		gc->gc.gc_refs = Py_Refcnt(FROM_GC(gc));
 		/* Python's cyclic gc should never see an incoming refcount
 		 * of 0:  if something decref'ed to 0, it should have been
 		 * deallocated immediately at that time.
@@ -291,7 +291,7 @@
 	traverseproc traverse;
 	PyGC_Head *gc = containers->gc.gc_next;
 	for (; gc != containers; gc=gc->gc.gc_next) {
-		traverse = FROM_GC(gc)->ob_type->tp_traverse;
+		traverse = Py_Type(FROM_GC(gc))->tp_traverse;
 		(void) traverse(FROM_GC(gc),
 			       (visitproc)visit_decref,
 			       NULL);
@@ -376,7 +376,7 @@
                          * the next object to visit.
                          */
                         PyObject *op = FROM_GC(gc);
-                        traverseproc traverse = op->ob_type->tp_traverse;
+                        traverseproc traverse = Py_Type(op)->tp_traverse;
                         assert(gc->gc.gc_refs > 0);
                         gc->gc.gc_refs = GC_REACHABLE;
                         (void) traverse(op,
@@ -472,7 +472,7 @@
 	PyGC_Head *gc = finalizers->gc.gc_next;
 	for (; gc != finalizers; gc = gc->gc.gc_next) {
 		/* Note that the finalizers list may grow during this. */
-		traverse = FROM_GC(gc)->ob_type->tp_traverse;
+		traverse = Py_Type(FROM_GC(gc))->tp_traverse;
 		(void) traverse(FROM_GC(gc),
 				(visitproc)visit_move,
 				(void *)finalizers);
@@ -517,7 +517,7 @@
 		assert(IS_TENTATIVELY_UNREACHABLE(op));
 		next = gc->gc.gc_next;
 
-		if (! PyType_SUPPORTS_WEAKREFS(op->ob_type))
+		if (! PyType_SUPPORTS_WEAKREFS(Py_Type(op)))
 			continue;
 
 		/* It supports weakrefs.  Does it have any? */
@@ -654,7 +654,7 @@
 	}
 	else if (debug & DEBUG_OBJECTS) {
 		PySys_WriteStderr("gc: %.100s <%.100s %p>\n",
-				  msg, op->ob_type->tp_name, op);
+				  msg, Py_Type(op)->tp_name, op);
 	}
 }
 
@@ -708,7 +708,7 @@
 			PyList_Append(garbage, op);
 		}
 		else {
-			if ((clear = op->ob_type->tp_clear) != NULL) {
+			if ((clear = Py_Type(op)->tp_clear) != NULL) {
 				Py_INCREF(op);
 				clear(op);
 				Py_DECREF(op);
@@ -1079,7 +1079,7 @@
 	traverseproc traverse;
 	for (gc = list->gc.gc_next; gc != list; gc = gc->gc.gc_next) {
 		obj = FROM_GC(gc);
-		traverse = obj->ob_type->tp_traverse;
+		traverse = Py_Type(obj)->tp_traverse;
 		if (obj == objs || obj == resultlist)
 			continue;
 		if (traverse(obj, (visitproc)referrersvisit, objs)) {
@@ -1136,7 +1136,7 @@
 
 		if (! PyObject_IS_GC(obj))
 			continue;
-		traverse = obj->ob_type->tp_traverse;
+		traverse = Py_Type(obj)->tp_traverse;
 		if (! traverse)
 			continue;
 		if (traverse(obj, (visitproc)referentsvisit, result)) {
@@ -1359,13 +1359,13 @@
 PyVarObject *
 _PyObject_GC_Resize(PyVarObject *op, Py_ssize_t nitems)
 {
-	const size_t basicsize = _PyObject_VAR_SIZE(op->ob_type, nitems);
+	const size_t basicsize = _PyObject_VAR_SIZE(Py_Type(op), nitems);
 	PyGC_Head *g = AS_GC(op);
 	g = (PyGC_Head *)PyObject_REALLOC(g,  sizeof(PyGC_Head) + basicsize);
 	if (g == NULL)
 		return (PyVarObject *)PyErr_NoMemory();
 	op = (PyVarObject *) FROM_GC(g);
-	op->ob_size = nitems;
+	Py_Size(op) = nitems;
 	return op;
 }