GH-118074: Executors in the COLD_EXITS array are not GC'able (#118117)

diff --git a/Misc/NEWS.d/next/Core and Builtins/2024-04-22-08-34-28.gh-issue-118074.5_JnIa.rst b/Misc/NEWS.d/next/Core and Builtins/2024-04-22-08-34-28.gh-issue-118074.5_JnIa.rst
new file mode 100644 (file)
index 0000000..69d29bc
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2024-04-22-08-34-28.gh-issue-118074.5_JnIa.rst
@@ -0,0 +1,2 @@
+Make sure that the Executor objects in the COLD_EXITS array aren't assumed
+to be GC-able (which would access bytes outside the object).

diff --git a/Python/optimizer.c b/Python/optimizer.c
index bb537c9111a51f302c205988feda0b36d6ac017b..5863336c0d9ecfeaf9b5a6121283b65a48e3e9ca 100644 (file)
--- a/Python/optimizer.c
+++ b/Python/optimizer.c
@@ -394,6 +394,15 @@ executor_traverse(PyObject *o, visitproc visit, void *arg)
     return 0;
 }
 
+static int
+executor_is_gc(PyObject *o)
+{
+    if ((PyObject *)&COLD_EXITS[0] <= o && o < (PyObject *)&COLD_EXITS[COLD_EXIT_COUNT]) {
+        return 0;
+    }
+    return 1;
+}
+
 PyTypeObject _PyUOpExecutor_Type = {
     PyVarObject_HEAD_INIT(&PyType_Type, 0)
     .tp_name = "uop_executor",
@@ -405,6 +414,7 @@ PyTypeObject _PyUOpExecutor_Type = {
     .tp_methods = executor_methods,
     .tp_traverse = executor_traverse,
     .tp_clear = executor_clear,
+    .tp_is_gc = executor_is_gc,
 };
 
 /* TO DO -- Generate these tables */