The tests now pass all combinations of -O/-OO and -B.  See also #7071
and #6292 for previous variations on the same theme.

test_versionpredicate needs a skip when sys.flags.optimize is true, but
I don’t know how to make that work with a DocTestSuite.

open() function instead of using StreamReaderWriter. Deprecate StreamReader,
StreamWriter, StreamReaderWriter, StreamRecoder and EncodedFile() of the codec
module. Use the builtin open() function or io.TextIOWrapper instead."

"It has not been approved !" wrote Marc-Andre Lemburg.

Warnings found by the Clang Static Analyzer."

Most people prefer ++ at the end of functions.

This should reduce memory usage.

Initial patch by Nir Aides.

StreamReaderWriter. Deprecate StreamReader, StreamWriter, StreamReaderWriter,
StreamRecoder and EncodedFile() of the codec module. Use the builtin open()
function or io.TextIOWrapper instead.

Make silent a false positive of the Clang Static Analyzer.

Bug found by the Clang Static Analyzer.

Bug found by the Clang Static Analyzer.

Dummy change to avoid a false positive with the Clang Static Analyzer.

In some cases, fullpath value is used whereas fullpath was not always
initialized. Warning found by the Clang Static Analyzer.

Warnings found by the Clang Static Analyzer.

Warnings found by the the Clang Static Analyzer.

returns None.