Issue #23996: Avoid a crash when a delegated generator raises an unnormalized StopIteration exception. Patch by Stefan Behnel.
diff --git a/Objects/genobject.c b/Objects/genobject.c
index 08d30bf..f125847 100644
--- a/Objects/genobject.c
+++ b/Objects/genobject.c
@@ -396,13 +396,30 @@
if (PyErr_ExceptionMatches(PyExc_StopIteration)) {
PyErr_Fetch(&et, &ev, &tb);
+ if (ev) {
+ /* exception will usually be normalised already */
+ if (Py_TYPE(ev) == (PyTypeObject *) et
+ || PyObject_IsInstance(ev, PyExc_StopIteration)) {
+ value = ((PyStopIterationObject *)ev)->value;
+ Py_INCREF(value);
+ Py_DECREF(ev);
+ } else if (et == PyExc_StopIteration) {
+ /* avoid normalisation and take ev as value */
+ value = ev;
+ } else {
+ /* normalisation required */
+ PyErr_NormalizeException(&et, &ev, &tb);
+ if (!PyObject_IsInstance(ev, PyExc_StopIteration)) {
+ PyErr_Restore(et, ev, tb);
+ return -1;
+ }
+ value = ((PyStopIterationObject *)ev)->value;
+ Py_INCREF(value);
+ Py_DECREF(ev);
+ }
+ }
Py_XDECREF(et);
Py_XDECREF(tb);
- if (ev) {
- value = ((PyStopIterationObject *)ev)->value;
- Py_INCREF(value);
- Py_DECREF(ev);
- }
} else if (PyErr_Occurred()) {
return -1;
}