[Python-checkins] [3.11] gh-105375: Improve array.array exception handling (GH-105594) (#105643)

[erlend-aasland]

https://github.com/python/cpython/commit/3c08e54ccfff5c43ba79bbb4a95ad9effb16519a
commit: 3c08e54ccfff5c43ba79bbb4a95ad9effb16519a
branch: 3.11
author: Miss Islington (bot) <31488909+miss-islington at users.noreply.github.com>
committer: erlend-aasland <erlend.aasland at protonmail.com>
date: 2023-06-11T10:22:31Z
summary:

[3.11] gh-105375: Improve array.array exception handling (GH-105594) (#105643)

Fix a bug where 'tp_richcompare' could end up overwriting an exception.
(cherry picked from commit 35cff545db7c7912046c0ce5627db2e4d2b60f57)

Co-authored-by: Erlend E. Aasland <erlend.aasland at protonmail.com>

files:
A Misc/NEWS.d/next/Library/2023-06-09-21-46-52.gh-issue-105375.yrJelV.rst
M Modules/arraymodule.c

diff --git a/Misc/NEWS.d/next/Library/2023-06-09-21-46-52.gh-issue-105375.yrJelV.rst b/Misc/NEWS.d/next/Library/2023-06-09-21-46-52.gh-issue-105375.yrJelV.rst
new file mode 100644
index 000000000000..21aea1b0b408
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2023-06-09-21-46-52.gh-issue-105375.yrJelV.rst
@@ -0,0 +1,2 @@
+Fix a bug in :class:`array.array` where an exception could end up being
+overwritten.
diff --git a/Modules/arraymodule.c b/Modules/arraymodule.c
index a04e6a4e070d..312ab92eb712 100644
--- a/Modules/arraymodule.c
+++ b/Modules/arraymodule.c
@@ -741,10 +741,12 @@ array_richcompare(PyObject *v, PyObject *w, int op)
     k = 1;
     for (i = 0; i < Py_SIZE(va) && i < Py_SIZE(wa); i++) {
         vi = getarrayitem(v, i);
+        if (vi == NULL) {
+            return NULL;
+        }
         wi = getarrayitem(w, i);
-        if (vi == NULL || wi == NULL) {
-            Py_XDECREF(vi);
-            Py_XDECREF(wi);
+        if (wi == NULL) {
+            Py_DECREF(vi);
             return NULL;
         }
         k = PyObject_RichCompareBool(vi, wi, Py_EQ);