[2.7] bpo-35441: Remove dead and buggy code related to PyList_SetItem(). (GH-11033) (GH-11234)

In _localemodule.c and selectmodule.c, remove dead code that would
cause double decrefs if run.

In addition, replace PyList_SetItem() with PyList_SET_ITEM() in cases
where a new list is populated and there is no possibility of an error.

In addition, check if the list changed size in the loop in array_array_fromlist().
(cherry picked from commit 99d56b53560b3867844472ae381fb3f858760621)

Co-authored-by: Zackery Spytz <zspytz@gmail.com>

1 files changed, 1 insertions, 4 deletions

diff --git a/Modules/selectmodule.c b/Modules/selectmodule.c
index 1dec6a1..dc22f10 100644
--- a/Modules/selectmodule.c
+++ b/Modules/selectmodule.c
@@ -601,10 +601,7 @@ poll_poll(pollObject *self, PyObject *args)
                 goto error;
             }
             PyTuple_SET_ITEM(value, 1, num);
-            if ((PyList_SetItem(result_list, j, value)) == -1) {
-                Py_DECREF(value);
-                goto error;
-            }
+            PyList_SET_ITEM(result_list, j, value);
             i++;
         }
     }