- interpreter startup and shutdown code moved to a new pylifecycle.c module - Py_OptimizeFlag moved into the new module with the other global flags
Issue #26563: Py_FatalError: disable faulthandler before trying to flush sys.stdout and sys.stderr.
Issue #26558: If Py_FatalError() is called without the GIL, don't try to print the current exception, nor try to flush stdout and stderr: only dump the traceback of Python threads.