From a1c49f6f09150f70f063417c8d67a38e59dde7ed Mon Sep 17 00:00:00 2001
From: "Miss Islington (bot)"
 <31488909+miss-islington@users.noreply.github.com>
Date: Tue, 26 Sep 2017 20:45:57 -0700
Subject: [PATCH] [3.6] bpo-31586: Use _count_element fast path for real dicts.
 (#3776)

(cherry picked from commit 31aca4bf79217e6ec4c1d056d3ad7ed4dd469c78)
---
 Modules/_collectionsmodule.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Modules/_collectionsmodule.c b/Modules/_collectionsmodule.c
index e7a24f3f05..af20d6edd9 100644
--- a/Modules/_collectionsmodule.c
+++ b/Modules/_collectionsmodule.c
@@ -2276,7 +2276,9 @@ _count_elements(PyObject *self, PyObject *args)
     dict_setitem = _PyType_LookupId(&PyDict_Type, &PyId___setitem__);
 
     if (mapping_get != NULL && mapping_get == dict_get &&
-        mapping_setitem != NULL && mapping_setitem == dict_setitem) {
+        mapping_setitem != NULL && mapping_setitem == dict_setitem &&
+        PyDict_Check(mapping))
+    {
         while (1) {
             /* Fast path advantages:
                    1. Eliminate double hashing
-- 
2.50.0