await causes crash

gistfile1.txt

ok 271 - new for Channel
Internal error: zeroed target thread ID in work pass

caused by this code:

for in () -> $in {
    ok (my $csv = Text::CSV.new, "new for Channel");
    my @d;
    my $ch = Channel.new;
    my $thr = start {
        react {
            whenever $ch -> \row {
                @d.push: row;
                LAST { done; }
                }
            }
        }
    $csv.CSV (in => $in, out => $ch, :!meta);
    await $thr;
    is-deeply ([@d], $full-aoa, "csv => Channel { s-in ($in) }");
    }

if I put a «say "await";» before «await $thr;» it always passes