From 34bf5460352030cc369c47c0f08e7c0b10d5fd11 Mon Sep 17 00:00:00 2001
From: Raymond Hettinger <raymond.hettinger@gmail.com>
Date: Tue, 25 Jun 2024 02:24:58 -0500
Subject: [PATCH] Fast case for count from zero

---
 Modules/_collectionsmodule.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/Modules/_collectionsmodule.c b/Modules/_collectionsmodule.c
index 644a90a8c71099..641d57a64c8357 100644
--- a/Modules/_collectionsmodule.c
+++ b/Modules/_collectionsmodule.c
@@ -2575,7 +2575,11 @@ _collections__count_elements_impl(PyObject *module, PyObject *mapping,
             oldval = PyObject_CallFunctionObjArgs(bound_get, key, zero, NULL);
             if (oldval == NULL)
                 break;
-            newval = PyNumber_Add(oldval, one);
+            if (oldval == zero) {
+                newval = Py_NewRef(one);
+            } else {
+                newval = PyNumber_Add(oldval, one);
+            }
             Py_DECREF(oldval);
             if (newval == NULL)
                 break;