Issue #26494: Fixed crash on iterating exhausting iterators.

Affected classes are generic sequence iterators, iterators of str, bytes,
bytearray, list, tuple, set, frozenset, dict, OrderedDict, corresponding
views and os.scandir() iterator.

1 files changed, 1 insertions, 1 deletions

diff --git a/Objects/tupleobject.c b/Objects/tupleobject.c
index 8e1b00b63d..5020aff3f4 100644
--- a/Objects/tupleobject.c
+++ b/Objects/tupleobject.c
@@ -961,8 +961,8 @@ tupleiter_next(tupleiterobject *it)
         return item;
     }
 
-    Py_DECREF(seq);
     it->it_seq = NULL;
+    Py_DECREF(seq);
     return NULL;
 }