python · pablogsal · Mar 27, 2021 · Mar 27, 2021 · Mar 27, 2021
diff --git a/Objects/typeobject.c b/Objects/typeobject.c
@@ -424,7 +424,7 @@ assign_version_tag(struct type_cache *cache, PyTypeObject *type)
    if (type->tp_version_tag == 0) {
        // Wrap-around or just starting Python - clear the whole cache
        type_cache_clear(cache, 1);
-        return 1;
+        return 0;
    }

    bases = type->tp_bases;
@@ -3361,6 +3361,7 @@ _PyType_Lookup(PyTypeObject *type, PyObject *name)
 #if MCACHE_STATS
        cache->hits++;
 #endif
+        assert(_PyType_HasFeature(type, Py_TPFLAGS_VALID_VERSION_TAG));
        return entry->value;
    }

@@ -3398,6 +3399,7 @@ _PyType_Lookup(PyTypeObject *type, PyObject *name)
            cache->misses++;
        }
 #endif
+        assert(_PyType_HasFeature(type, Py_TPFLAGS_VALID_VERSION_TAG));
        Py_SETREF(entry->name, Py_NewRef(name));
    }
    return res;