From 50d62bd40a30db62f435712af1011d7607140796 Mon Sep 17 00:00:00 2001
From: Donghee Na <donghee.na@python.org>
Date: Fri, 19 Apr 2024 07:52:19 +0900
Subject: [PATCH] gh-112069: Do not require lock if the set has never been
 exposed.

---
 Objects/setobject.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Objects/setobject.c b/Objects/setobject.c
index 7af0ae166f9da3..04788ff197d9c0 100644
--- a/Objects/setobject.c
+++ b/Objects/setobject.c
@@ -2334,6 +2334,12 @@ set_init(PySetObject *self, PyObject *args, PyObject *kwds)
     if (!PyArg_UnpackTuple(args, Py_TYPE(self)->tp_name, 0, 1, &iterable))
         return -1;
 
+    if (self->fill == 0 && Py_REFCNT(self) == 1) {
+        if (iterable == NULL) {
+            return 0;
+        }
+        return set_update_local(self, iterable);
+    }
     Py_BEGIN_CRITICAL_SECTION(self);
     if (self->fill)
         set_clear_internal(self);