PEP 3123: Provide forward compatibility with Python 3.0, while keeping
backwards compatibility. Add Py_Refcnt, Py_Type, Py_Size, and
PyVarObject_HEAD_INIT.
diff --git a/Include/floatobject.h b/Include/floatobject.h
index f695de8..bfbc580 100644
--- a/Include/floatobject.h
+++ b/Include/floatobject.h
@@ -19,7 +19,7 @@
 PyAPI_DATA(PyTypeObject) PyFloat_Type;
 
 #define PyFloat_Check(op) PyObject_TypeCheck(op, &PyFloat_Type)
-#define PyFloat_CheckExact(op) ((op)->ob_type == &PyFloat_Type)
+#define PyFloat_CheckExact(op) (Py_Type(op) == &PyFloat_Type)
 
 /* Return Python float from string PyObject.  Second argument ignored on
    input, and, if non-NULL, NULL is stored into *junk (this tried to serve a