bpo-38644: Add Py_EnterRecursiveCall() to the limited API (GH-17046)

Provide Py_EnterRecursiveCall() and Py_LeaveRecursiveCall() as
regular functions for the limited API. Previously, there were defined
as macros, but these macros didn't work with the limited API which
cannot access PyThreadState.recursion_depth field.

Remove _Py_CheckRecursionLimit from the stable ABI.

Add Include/cpython/ceval.h header file.

1 files changed, 9 insertions, 3 deletions

diff --git a/Doc/c-api/exceptions.rst b/Doc/c-api/exceptions.rst
index c7ba74c..a042c6e 100644
--- a/Doc/c-api/exceptions.rst
+++ b/Doc/c-api/exceptions.rst
@@ -715,15 +715,21 @@ recursion depth automatically).
    case, a :exc:`RecursionError` is set and a nonzero value is returned.
    Otherwise, zero is returned.
 
-   *where* should be a string such as ``" in instance check"`` to be
-   concatenated to the :exc:`RecursionError` message caused by the recursion
+   *where* should be a UTF-8 encoded string such as ``" in instance check"`` to
+   be concatenated to the :exc:`RecursionError` message caused by the recursion
    depth limit.
 
-.. c:function:: void Py_LeaveRecursiveCall()
+   .. versionchanged:: 3.9
+      This function is now also available in the limited API.
+
+.. c:function:: void Py_LeaveRecursiveCall(void)
 
    Ends a :c:func:`Py_EnterRecursiveCall`.  Must be called once for each
    *successful* invocation of :c:func:`Py_EnterRecursiveCall`.
 
+   .. versionchanged:: 3.9
+      This function is now also available in the limited API.
+
 Properly implementing :c:member:`~PyTypeObject.tp_repr` for container types requires
 special recursion handling.  In addition to protecting the stack,
 :c:member:`~PyTypeObject.tp_repr` also needs to track objects to prevent cycles.  The