diff --git a/Objects/typeobject.c b/Objects/typeobject.c
index cc389bc3d6f..e67945db9af 100644
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -5009,6 +5009,7 @@ clear_static_tp_subclasses(PyTypeObject *type)
        going to leak.  This mostly only affects embedding scenarios.
      */
 
+#ifndef NDEBUG
     // For now we just do a sanity check and then clear tp_subclasses.
     Py_ssize_t i = 0;
     PyObject *key, *ref;  // borrowed ref
@@ -5021,6 +5022,7 @@ clear_static_tp_subclasses(PyTypeObject *type)
         assert(!(subclass->tp_flags & _Py_TPFLAGS_STATIC_BUILTIN));
         Py_DECREF(subclass);
     }
+#endif
 
     clear_tp_subclasses(type);
 }