Malformed UTF-8?

[ToddAndMargo]

rakudo-pkg-Fedora28-2018.05-01.x86_64.rpm
$ perl6 -v
This is Rakudo version 2018.05 built on MoarVM version 2018.05
implementing Perl 6.c.

What did I do wrong, this time?

Malformed UTF-8
  in sub RotateZipFile at /home/linuxutil/CimCheck.pl6 line 290

290:   @ReverseLogs = @Logs.sort: {my ($month, $day, $year, $hour, 
$minute, $second) = .comb(/\d+/);($year // 0, $month // 0, $day // 0, 
$hour // 0, $minute // 0,$second // 0, $_);}