[3.7] bpo-33824, bpo-32030: Fix pymain_read_conf() (GH-7712) by miss-islington · Pull Request #7730 · python/cpython

@vstinner @miss-islington

Fix "LC_ALL=C python3.7 -V": reset properly the command line parser
when the encoding changes after reading the Python configuration.

Fix pymain_read_conf(): use memset(0) to reset properly cmdline.
(cherry picked from commit 6c5a4b3)

Co-authored-by: Victor Stinner <vstinner@redhat.com>

vstinner