Issue #3945: Fixed compile error on cygwin. (initializer element is not constant)
Reviewed by Amaury Forgeot d'Arc.
diff --git a/Modules/_fileio.c b/Modules/_fileio.c
index c3d61b4..d7f7893 100644
--- a/Modules/_fileio.c
+++ b/Modules/_fileio.c
@@ -831,7 +831,7 @@
 };
 
 PyTypeObject PyFileIO_Type = {
-	PyVarObject_HEAD_INIT(&PyType_Type, 0)
+	PyVarObject_HEAD_INIT(NULL, 0)
 	"_FileIO",
 	sizeof(PyFileIOObject),
 	0,