Issue #22570: Renamed Py_SETREF to Py_XSETREF.
diff --git a/Parser/tokenizer.c b/Parser/tokenizer.c
index 50ce2e8..184ffe7 100644
--- a/Parser/tokenizer.c
+++ b/Parser/tokenizer.c
@@ -526,7 +526,7 @@
         goto cleanup;
 
     readline = _PyObject_GetAttrId(stream, &PyId_readline);
-    Py_SETREF(tok->decoding_readline, readline);
+    Py_XSETREF(tok->decoding_readline, readline);
     if (pos > 0) {
         if (PyObject_CallObject(readline, NULL) == NULL) {
             readline = NULL;