I found that it put a '\n' between the key and data in the cloned hash

That can only be an artifact of the way you are inspecting the cloned hash, because Clone::clone() adds nothing:

use Clone qw[ clone ];;

my $n = 0; 
my %hash = map{ $_, ++$n} 'a' .. 'e';;

pp \%hash;;
{ a => 1, b => 2, c => 3, d => 4, e => 5 }

my $copy = clone \%hash;;

pp $copy;;
{ a => 1, b => 2, c => 3, d => 4, e => 5 }
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