There is an ongoing outage on the primary CPAN mirror. It is possible to work around the issue by using MetaCPAN as a mirror.

./make_build_perl5; 
perl util/src_to_blib.pl;
util/prove6 t/01-sanity

There might be a few modules missing, install them from CPAN. You will see the tc files after you run the tests.

This script is dumb about finding the right 'make' to use. You may need to edit it to provide the correct value.