basicsize and itemsize are Py_ssize_t #9688

Lib/test/test_types.py

@@ -550,6 +550,11 @@ def test_format_spec_errors(self):
         for code in 'xXobns':
             self.assertRaises(ValueError, format, 0, ',' + code)
 
+    def test_internal_sizes(self):
+        self.assertGreater(object.__basicsize__, 0)
+        self.assertGreater(tuple.__itemsize__, 0)
+
+
 def test_main():
     run_unittest(TypesTests)
 

Misc/NEWS

@@ -12,6 +12,8 @@ What's New in Python 3.2 Alpha 2?
 Core and Builtins
 -----------------
 
+- Issue #9688: __basicsize__ and __itemsize__ must be accessed as Py_ssize_t.
+
 - Issue #9684: Added a definition for SIZEOF_WCHAR_T to PC/pyconfig.h,
   to match the pyconfig.h generated by configure on other systems.
 

Objects/typeobject.c

@@ -189,8 +189,8 @@ assign_version_tag(PyTypeObject *type)
 
 
 static PyMemberDef type_members[] = {
-    {"__basicsize__", T_INT, offsetof(PyTypeObject,tp_basicsize),READONLY},
-    {"__itemsize__", T_INT, offsetof(PyTypeObject, tp_itemsize), READONLY},
+    {"__basicsize__", T_PYSSIZET, offsetof(PyTypeObject,tp_basicsize),READONLY},
+    {"__itemsize__", T_PYSSIZET, offsetof(PyTypeObject, tp_itemsize), READONLY},
     {"__flags__", T_LONG, offsetof(PyTypeObject, tp_flags), READONLY},
     {"__weakrefoffset__", T_LONG,
      offsetof(PyTypeObject, tp_weaklistoffset), READONLY},