From 98ccba8344a349d1bbc27718215156478ffa19ed Mon Sep 17 00:00:00 2001
From: Victor Stinner <victor.stinner@gmail.com>
Date: Wed, 18 Jan 2017 14:06:38 +0100
Subject: [PATCH] _PyObject_FastCallKeywords() now checks !PyErr_Occurred()

Issue #29259. All other functions calling functions start with the similar
assertion.
---
 Objects/abstract.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Objects/abstract.c b/Objects/abstract.c
index 4b32fedccf0..1132b842ca1 100644
--- a/Objects/abstract.c
+++ b/Objects/abstract.c
@@ -2482,6 +2482,11 @@ PyObject *
 _PyObject_FastCallKeywords(PyObject *callable, PyObject **stack, Py_ssize_t nargs,
                            PyObject *kwnames)
 {
+    /* _PyObject_FastCallKeywords() must not be called with an exception set,
+       because it can clear it (directly or indirectly) and so the
+       caller loses its exception */
+    assert(!PyErr_Occurred());
+
     assert(nargs >= 0);
     assert(kwnames == NULL || PyTuple_CheckExact(kwnames));