May be you can follow this simple example and try modifying to see where you are getting the problem: 
use Data::Dumper;
my %myhash = {};
build_hash(\%myhash);
print Dumper(\%myhash);

sub build_hash {
    my $href = shift;
    my %results = (1,2,3,4);;
     %{$href} = %results;
#    print Dumper($href);
}

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artist

In reply to Re: Preserving hash structure after subroutine call by artist
in thread Preserving hash structure after subroutine call by Anonymous Monk

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