gh-109700: fix memory error handling in PyDict_SetDefault (GH-136338)

kumaraditya303 · miss-islington · commit d62c8bc79c8a · 2025-07-06T15:18:17.000Z
(cherry picked from commit d22e073) Co-authored-by: Kumar Aditya <kumaraditya@python.org>
diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2025-07-06-14-53-19.gh-issue-109700.KVNQQi.rst b/Misc/NEWS.d/next/Core_and_Builtins/2025-07-06-14-53-19.gh-issue-109700.KVNQQi.rst
@@ -0,0 +1 @@
+Fix memory error handling in :c:func:`PyDict_SetDefault`.
diff --git a/Objects/dictobject.c b/Objects/dictobject.c
@@ -4411,6 +4411,7 @@ dict_setdefault_ref_lock_held(PyObject *d, PyObject *key, PyObject *default_valu
             if (result) {
                 *result = NULL;
             }
+            return -1;
         }
 
         STORE_USED(mp, mp->ma_used + 1);

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1 @@`
	`1`	+Fix memory error handling in :c:func:`PyDict_SetDefault`.
Original file line number	Diff line number	Diff line change
`@@ -4411,6 +4411,7 @@ dict_setdefault_ref_lock_held(PyObject d, PyObject key, PyObject *default_valu`
`4411`	`4411`	`if (result) {`
`4412`	`4412`	`*result = NULL;`
`4413`	`4413`	`}`
	`4414`	`+ return -1;`
`4414`	`4415`	`}`
`4415`	`4416`
`4416`	`4417`	`STORE_USED(mp, mp->ma_used + 1);`