changed builtin_sum to use PyNumber_InPlaceAdd -- unchanged semantics but

fixes performance bug with sum(lotsoflists, []).

diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c
index e10d16ba65f416742f4c5828ffec838bbd7977f6..22d728e60fa70b7998bfb00a8fb3d0822fa691d1 100644 (file)
--- a/Python/bltinmodule.c
+++ b/Python/bltinmodule.c
@@ -1840,7 +1840,7 @@ builtin_sum(PyObject *self, PyObject *args)
                        }
                        break;
                }
-               temp = PyNumber_Add(result, item);
+               temp = PyNumber_InPlaceAdd(result, item);
                Py_DECREF(result);
                Py_DECREF(item);
                result = temp;