This appears to be a perl bug. You can see in this very stripped down example that the correct hashes are made but they are not pushed into the array(ref or plain) as expected.

use Data::Dumper;
my (@data, @col_names, %tmp, $record);
@data = <DATA>;
chomp @data;
@col_names = split ',', shift @data;
while(my $line = shift @data) {
    last unless $line;
    @tmp{@col_names} = split ',', $line;
    print 'Inside ', Dumper \%tmp;
    push @{$record}, \%tmp;
}
push @{$record}, { 'what ', 'the £$%^& ?' };
print 'Outside ', Dumper $record;
print 'Record 0 ', %{$record->[0]}, "\n";
print 'Record 1 ', %{$record->[1]}, "\n";
print 'Record 2 ', %{$record->[2]}, "\n";
print 'Record 3 ', %{$record->[3]}, "\n";

__DATA__
foo,bar
333,aaa
444,bbb
555,ccc

__END__
Inside $VAR1 = {
          'foo' => '333',
          'bar' => 'aaa'
        };
Inside $VAR1 = {
          'foo' => '444',
          'bar' => 'bbb'
        };
Inside $VAR1 = {
          'foo' => '555',
          'bar' => 'ccc'
        };
Outside $VAR1 = [
          {
            'foo' => '555',
            'bar' => 'ccc'
          },
          $VAR1->[0],
          $VAR1->[0],
          {
            'what ' => 'the £$%^& ?'
          }
        ];
Record 0 foo555barccc
Record 1 foo555barccc
Record 2 foo555barccc
Record 3 what the £$%^& ?
[download]

cheers

tachyon

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