Failure on AppVeyor on my PR 14029 (which is unrelated):
test_subinterpreter (test.test__xxsubinterpreters.IsRunningTests) ... Exception in thread Thread-8:
Traceback (most recent call last):
File "C:\projects\cpython\lib\threading.py", line 923, in _bootstrap_inner
self.run()
File "C:\projects\cpython\lib\threading.py", line 865, in run
self._target(*self._args, **self._kwargs)
File "C:\projects\cpython\lib\test\test__xxsubinterpreters.py", line 51, in run
interpreters.run_string(interp, dedent(f"""
RuntimeError: unrecognized interpreter ID 46
FAIL
FAIL: test_subinterpreter (test.test__xxsubinterpreters.IsRunningTests)
----------------------------------------------------------------------
Traceback (most recent call last):
File "C:\projects\cpython\lib\test\test__xxsubinterpreters.py", line 492, in test_subinterpreter
self.assertTrue(interpreters.is_running(interp))
AssertionError: False is not true
test__xxsubinterpreters passed when run again.