I get a panic when I run the above code with perl 5.8.5. It works, however, with perl 5.10.0:

$ uname -srpio
Linux 2.6.9-55.0.12.EL i686 i386 GNU/Linux

# List::Util is up to date (1.19).

$ perl5.8.5 -d:DProf -w
use strict;
use List::Util qw(shuffle);
my @train = (1, 2, 3, 4, 1, 2, 4, 4, 1, 2, 3, 4, 1);
my @test = shuffle @train;
__END__
panic: pad_sv po at - line 4.

$ perl5.10.0 -d:DProf -w
use strict;
use List::Util qw(shuffle);
my @train = (1, 2, 3, 4, 1, 2, 4, 4, 1, 2, 3, 4, 1);
my @test = shuffle @train;
__END__
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