[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>

2 files changed, 3 insertions, 3 deletions

diff --git a/Python/ceval.c b/Python/ceval.c
index b561cd0f30..e1140a8e40 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -5247,7 +5247,7 @@ getarray(long a[256])
             Py_DECREF(l);
             return NULL;
         }
-        PyList_SetItem(l, i, x);
+        PyList_SET_ITEM(l, i, x);
     }
     for (i = 0; i < 256; i++)
         a[i] = 0;
@@ -5269,7 +5269,7 @@ _Py_GetDXProfile(PyObject *self, PyObject *args)
             Py_DECREF(l);
             return NULL;
         }
-        PyList_SetItem(l, i, x);
+        PyList_SET_ITEM(l, i, x);
     }
     return l;
 #endif
diff --git a/Python/sysmodule.c b/Python/sysmodule.c
index b153ef6338..fdb7af2f5f 100644
--- a/Python/sysmodule.c
+++ b/Python/sysmodule.c
@@ -1555,7 +1555,7 @@ makepathobject(char *path, int delim)
             Py_DECREF(v);
             return NULL;
         }
-        PyList_SetItem(v, i, w);
+        PyList_SET_ITEM(v, i, w);
         if (*p == '\0')
             break;
         path = p+1;