diff --git a/Objects/tupleobject.c b/Objects/tupleobject.c
index c0b59c0..1453463 100644
--- a/Objects/tupleobject.c
+++ b/Objects/tupleobject.c
@@ -486,8 +486,7 @@
         Py_INCREF(a);
         return (PyObject *)a;
     }
-    if (Py_SIZE(a) > PY_SSIZE_T_MAX - Py_SIZE(b))
-        return PyErr_NoMemory();
+    assert((size_t)Py_SIZE(a) + (size_t)Py_SIZE(b) < PY_SSIZE_T_MAX);
     size = Py_SIZE(a) + Py_SIZE(b);
     if (size == 0) {
         return PyTuple_New(0);