python · encukou · Aug 25, 2025 · Jun 23, 2025 · Jun 24, 2025 · Jun 24, 2025
diff --git a/Doc/c-api/typeobj.rst b/Doc/c-api/typeobj.rst
@@ -1287,6 +1287,15 @@ and :c:data:`PyType_Type` effectively act as defaults.)
       :c:member:`~PyTypeObject.tp_weaklistoffset` field is set in a superclass.
 
 
+   .. c:macro:: Py_TPFLAGS_PREHEADER
+
+      This is a shorthand for checking is :c:macro:`Py_TPFLAGS_MANAGED_DICT` or
+      :c:macro:`Py_TPFLAGS_MANAGED_WEAKREF` present. Supposed only for internal
+      usage.
+
+      .. versionadded:: 3.12
+
+
    .. c:macro:: Py_TPFLAGS_ITEMS_AT_END
 
       Only usable with variable-size types, i.e. ones with non-zero

diff --git a/Include/object.h b/Include/object.h
@@ -534,6 +534,9 @@ given type object has a specified feature.
  */
 #define Py_TPFLAGS_MANAGED_DICT (1 << 4)
 
+/* Type has dictionary or weakref pointers that are managed by VM and has
+ * to allocate space to store these.
+ */
 #define Py_TPFLAGS_PREHEADER (Py_TPFLAGS_MANAGED_WEAKREF | Py_TPFLAGS_MANAGED_DICT)
 
 /* Set if instances of the type object are treated as sequences for pattern matching */

diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2025-06-24-13-08-15.gh-issue-95245.3whjTE.rst b/Misc/NEWS.d/next/Core_and_Builtins/2025-06-24-13-08-15.gh-issue-95245.3whjTE.rst
@@ -0,0 +1 @@
+Add documnetation for :c:macro:`Py_TPFLAGS_PREHEADER`
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		Add documnetation for :c:macro:`Py_TPFLAGS_PREHEADER`