From 48354b91805ac320609d5e59f8fa82f5b379599f Mon Sep 17 00:00:00 2001
From: Eric Snow <ericsnowcurrently@gmail.com>
Date: Thu, 27 Apr 2023 11:04:29 -0600
Subject: [PATCH] Fix _PyStaticType_InitBuiltin() for subinterpreters.

---
 Objects/typeobject.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Objects/typeobject.c b/Objects/typeobject.c
index 0c7bea09a4e6ff0..a4258f300f5f6be 100644
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -6644,6 +6644,10 @@ type_ready_pre_checks(PyTypeObject *type)
 static int
 type_ready_set_bases(PyTypeObject *type)
 {
+    if (lookup_tp_bases(type) != NULL) {
+        return 0;
+    }
+
     /* Initialize tp_base (defaults to BaseObject unless that's us) */
     PyTypeObject *base = type->tp_base;
     if (base == NULL && type != &PyBaseObject_Type) {
@@ -7183,6 +7187,11 @@ _PyStaticType_InitBuiltin(PyTypeObject *self)
     if (self->tp_flags & Py_TPFLAGS_READY) {
         assert(self->tp_flags & _Py_TPFLAGS_STATIC_BUILTIN);
         assert(_PyType_CheckConsistency(self));
+        /* We must explicitly set these for subinterpreters.
+           tp_subclasses is set lazily. */
+        type_ready_set_dict(self);
+        type_ready_set_bases(self);
+        type_ready_mro(self);
         return 0;
     }