From: sobolevn <mail@sobolevn.me>
Date: Tue, 24 Jun 2025 16:33:25 +0000 (+0300)
Subject: gh-135878: Fix crash in `types.SimpleNamespace.__repr__` (#135889)
X-Git-Tag: v3.15.0a1~1197
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=b3ab94acd308591bbdf264f1722fedc7ee25d6fa;p=thirdparty%2FPython%2Fcpython.git

gh-135878: Fix crash in `types.SimpleNamespace.__repr__` (#135889)

Co-authored-by: Peter Bierma <zintensitydev@gmail.com>
---

diff --git a/Misc/NEWS.d/next/Library/2025-06-24-14-43-24.gh-issue-135878.Db4roX.rst b/Misc/NEWS.d/next/Library/2025-06-24-14-43-24.gh-issue-135878.Db4roX.rst
new file mode 100644
index 000000000000..969cf2dfa408
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2025-06-24-14-43-24.gh-issue-135878.Db4roX.rst
@@ -0,0 +1,3 @@
+Fixes a crash of :class:`types.SimpleNamespace` on :term:`free threading` builds,
+when several threads were calling its :meth:`~object.__repr__` method at the
+same time.
diff --git a/Objects/namespaceobject.c b/Objects/namespaceobject.c
index caebe6bf5435..0fc2bcea4cb0 100644
--- a/Objects/namespaceobject.c
+++ b/Objects/namespaceobject.c
@@ -124,9 +124,10 @@ namespace_repr(PyObject *ns)
         if (PyUnicode_Check(key) && PyUnicode_GET_LENGTH(key) > 0) {
             PyObject *value, *item;
 
-            value = PyDict_GetItemWithError(d, key);
-            if (value != NULL) {
+            int has_key = PyDict_GetItemRef(d, key, &value);
+            if (has_key == 1) {
                 item = PyUnicode_FromFormat("%U=%R", key, value);
+                Py_DECREF(value);
                 if (item == NULL) {
                     loop_error = 1;
                 }
@@ -135,7 +136,7 @@ namespace_repr(PyObject *ns)
                     Py_DECREF(item);
                 }
             }
-            else if (PyErr_Occurred()) {
+            else if (has_key < 0) {
                 loop_error = 1;
             }
         }