From 43dce09f6f99a7018594c89c15868ecad3b3e2d7 Mon Sep 17 00:00:00 2001
From: Victor Stinner <vstinner@redhat.com>
Date: Mon, 10 Jun 2019 22:30:23 +0200
Subject: [PATCH] bpo-36402: Fix test_threading.test_threads_join_2()

Fix test_threading.test_threads_join_2(): run the test into a
subprocess, rather than in a subinterpreter, to avoid a race
condition.
---
 Lib/test/test_threading.py                                  | 6 ++++--
 .../next/Tests/2019-06-10-22-45-26.bpo-36402.QqZnfC.rst     | 2 ++
 2 files changed, 6 insertions(+), 2 deletions(-)
 create mode 100644 Misc/NEWS.d/next/Tests/2019-06-10-22-45-26.bpo-36402.QqZnfC.rst

diff --git a/Lib/test/test_threading.py b/Lib/test/test_threading.py
index 6ac4ea9623de0d..512789ce5cffce 100644
--- a/Lib/test/test_threading.py
+++ b/Lib/test/test_threading.py
@@ -888,8 +888,10 @@ def f():
                 os.write(%d, b"x")
             threading.Thread(target=f).start()
             """ % (w,)
-        ret = test.support.run_in_subinterp(code)
-        self.assertEqual(ret, 0)
+        import subprocess
+        proc = subprocess.run([sys.executable, "-c", code], stderr=subprocess.PIPE, pass_fds=[w])
+        self.assertEqual(proc.stderr, b'', proc)
+        self.assertEqual(proc.returncode, 0, proc)
         # The thread was joined properly.
         self.assertEqual(os.read(r, 1), b"x")
 
diff --git a/Misc/NEWS.d/next/Tests/2019-06-10-22-45-26.bpo-36402.QqZnfC.rst b/Misc/NEWS.d/next/Tests/2019-06-10-22-45-26.bpo-36402.QqZnfC.rst
new file mode 100644
index 00000000000000..9a96c5396b6d17
--- /dev/null
+++ b/Misc/NEWS.d/next/Tests/2019-06-10-22-45-26.bpo-36402.QqZnfC.rst
@@ -0,0 +1,2 @@
+Fix ``test_threading.test_threads_join_2()``: run the test into a
+subprocess, rather than in a subinterpreter, to avoid a race condition.