From 3f745bf1d90a75a0e3df5ba4d59b3ffbb71e3ebc Mon Sep 17 00:00:00 2001
From: Victor Stinner <victor.stinner@gmail.com>
Date: Fri, 19 Aug 2016 16:42:42 +0200
Subject: [PATCH] PyEval_CallObjectWithKeywords() uses fast call

Issue #27128: Modify PyEval_CallObjectWithKeywords() to use
_PyObject_FastCall() when args==NULL and kw==NULL. It avoids the creation of a
temporary empty tuple for positional arguments.
---
 Python/ceval.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Python/ceval.c b/Python/ceval.c
index b9b21d14be4..75eaa8110a2 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -4592,6 +4592,10 @@ PyEval_CallObjectWithKeywords(PyObject *func, PyObject *arg, PyObject *kw)
 #endif
 
     if (arg == NULL) {
+        if (kw == NULL) {
+            return _PyObject_FastCall(func, NULL, 0, 0);
+        }
+
         arg = PyTuple_New(0);
         if (arg == NULL)
             return NULL;