#6416: Fix compilation of the select module on Windows, as well as test_subprocess:
PIPE_BUF is not defined on Windows, and probably has no meaning there.
Anyway the subprocess module uses another way to perform non-blocking reads (with a thread)
diff --git a/Lib/test/test_subprocess.py b/Lib/test/test_subprocess.py
index 5add023..1693c6b 100644
--- a/Lib/test/test_subprocess.py
+++ b/Lib/test/test_subprocess.py
@@ -769,7 +769,7 @@
unit_tests = [ProcessTestCase]
-if subprocess._has_poll:
+if getattr(subprocess, '_has_poll', False):
class ProcessTestCaseNoPoll(ProcessTestCase):
def setUp(self):
subprocess._has_poll = False