This works now (and the test in S02-names-vars/list_array_perl.t is unfudged):
$ ./perl6-j -e 'my $foo = [42 ]; $foo[1] = $foo; say $foo.perl; say $foo.perl.EVAL' ((my @Array_1924162593) = $[42, @Array_1924162593]) (\Array_532302454 = [[42 Array_532302454]]) I'm closing this ticket as 'resolved'.