Try splitting the declaration and assignment onto two lines.

sub odd_args {
  my($this, $args);
  ($this, %$args) = @_;
  print $args->{x},"\n";
}
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This still works on 5.6.1 and I think should get around the problem on 5.8 although I can't test it.

---
print map { my ($m)=1<<hex($_)&11?' ':'';
$m.=substr('AHJPacehklnorstu',hex($_),1) }
split //,'2fde0abe76c36c914586c';
[download]