From: Guido van Rossum <guido@python.org>
Date: Mon, 8 Apr 2002 01:39:56 +0000 (+0000)
Subject: - A type can now inherit its metatype from its base type.  Previously,
X-Git-Tag: v2.2.1~8
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=e5ea439bc8f1a5a77fa0ee2c1d11b7a0ada83e9e;p=thirdparty%2FPython%2Fcpython.git

- A type can now inherit its metatype from its base type.  Previously,
  when PyType_Ready() was called, if ob_type was found to be NULL, it
  was always set to &PyType_Type; now it is set to base->ob_type,
  where base is tp_base, defaulting to &PyObject_Type.
---

diff --git a/Misc/NEWS b/Misc/NEWS
index 5098898e8093..fc3902bd348c 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -20,6 +20,11 @@ Library
 
 C API
 
+- A type can now inherit its metatype from its base type.  Previously,
+  when PyType_Ready() was called, if ob_type was found to be NULL, it
+  was always set to &PyType_Type; now it is set to base->ob_type,
+  where base is tp_base, defaulting to &PyObject_Type.
+
 - PyType_Ready() accidentally did not inherit tp_is_gc; now it does.
 
 Windows
diff --git a/Objects/typeobject.c b/Objects/typeobject.c
index 5ec5784c94e3..158c0ed1f648 100644
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -2002,17 +2002,17 @@ PyType_Ready(PyTypeObject *type)
 
 	type->tp_flags |= Py_TPFLAGS_READYING;
 
-	/* Initialize ob_type if NULL.  This means extensions that want to be
-	   compilable separately on Windows can call PyType_Ready() instead of
-	   initializing the ob_type field of their type objects. */
-	if (type->ob_type == NULL)
-		type->ob_type = &PyType_Type;
-
 	/* Initialize tp_base (defaults to BaseObject unless that's us) */
 	base = type->tp_base;
 	if (base == NULL && type != &PyBaseObject_Type)
 		base = type->tp_base = &PyBaseObject_Type;
 
+	/* Initialize ob_type if NULL.  This means extensions that want to be
+	   compilable separately on Windows can call PyType_Ready() instead of
+	   initializing the ob_type field of their type objects. */
+	if (type->ob_type == NULL)
+		type->ob_type = base->ob_type;
+
 	/* Initialize tp_bases */
 	bases = type->tp_bases;
 	if (bases == NULL) {