Issue #18439: Make patchcheck work on Windows for ACKS, NEWS.
Add sanity check to PyGrammar_LabelRepr() in order to catch invalid tokens when debugging
a new grammar.
CID 715360
merge
Issue #15905: Fix theoretical buffer overflow in handling of sys.argv[0],
prefix and exec_prefix if the operation system does not obey MAXPATHLEN.
Some compilers complain about 'control reaches end of non-void function'
because they don't understand that Py_FatalError() terminates the program.
Issue #17944: test_zipfile now discoverable and uses subclassing to
generate tests for different compression types.  Fixed a bug with skipping
some tests due to use of exhausted iterators.