e.g. http://www.cpantesters.org/cpan/report/
85472df4-1d3c-11e3-a7cb-ca49e0cbff33
even though we screen out empty paths before joining with : !
# remember the original value of this, in case we are already running inside a
# local::lib
my $orig_llr = $ENV{PERL_LOCAL_LIB_ROOT} || '';
+$orig_llr = '' if $orig_llr eq $Config{path_sep};
my $dir1 = mk_temp_dir('test_local_lib-XXXXX');
my $dir2 = mk_temp_dir('test_local_lib-XXXXX');