Adjust docs

Author: encukou

Doc/c-api/module.rst

@@ -230,6 +230,9 @@ Feature slots
    When creating a module, Python checks the value of this slot
    using :c:func:`PyABIInfo_Check`.
 
+   This slot is required, except for modules created from
+   :c:struct:`PyModuleDef`.
+
    .. versionadded:: 3.15
 
 .. c:macro:: Py_mod_multiple_interpreters
@@ -620,9 +623,9 @@ rather than from an extension's :ref:`export hook <extension-export-hook>`.
    and the :py:class:`~importlib.machinery.ModuleSpec` *spec*.
 
    The *slots* argument must point to an array of :c:type:`PyModuleDef_Slot`
-   structures, terminated by an entry slot with slot ID of 0
+   structures, terminated by an entry with slot ID of 0
    (typically written as ``{0}`` or ``{0, NULL}`` in C).
-   The *slots* argument may not be ``NULL``.
+   The array must include a :c:data:`Py_mod_abi` entry.
 
    The *spec* argument may be any ``ModuleSpec``-like object, as described
    in :c:macro:`Py_mod_create` documentation.

Doc/extending/first-extension-module.rst

@@ -265,12 +265,19 @@ Define this array just before your export hook:
 
 .. code-block:: c
 
+   PyABIInfo_VAR(abi_info);
+
    static PyModuleDef_Slot spam_slots[] = {
+      {Py_mod_abi, &abi_info},
       {Py_mod_name, "spam"},
       {Py_mod_doc, "A wonderful module with an example function"},
       {0, NULL}
    };
 
+The ``PyABIInfo_VAR(abi_info);`` macro and the :c:data:`Py_mod_abi` slot
+are a bit of boilerplate that helps prevent extensions compiled for
+a different version of Python from crashing the interpreter.
+
 For both :c:data:`Py_mod_name` and :c:data:`Py_mod_doc`, the values are C
 strings -- that is, NUL-terminated, UTF-8 encoded byte arrays.
 

Doc/includes/capi-extension/spammodule-01.c

@@ -35,7 +35,10 @@ static PyMethodDef spam_methods[] = {
 
 /// Module slot table
 
+PyABIInfo_VAR(abi_info);
+
 static PyModuleDef_Slot spam_slots[] = {
+    {Py_mod_abi, &abi_info},
     {Py_mod_name, "spam"},
     {Py_mod_doc, "A wonderful module with an example function"},
     {Py_mod_methods, spam_methods},

Misc/NEWS.d/next/C_API/2026-03-31-13-33-41.gh-issue-146636.5do3wt.rst

@@ -1,2 +1,3 @@
-The :c:data:`Py_mod_abi` slot is now mandatory for modules created using the
-:c:func:`PyModExport_* <PyModExport_modulename>` export hook.
+The :c:data:`Py_mod_abi` slot is now mandatory for modules created from a
+slots array (using :c:func:`PyModule_FromSlotsAndSpec` or the
+:c:func:`PyModExport_* <PyModExport_modulename>` export hook).