use strict;
use warnings;

use Benchmark qw( cmpthese );

my $passes = 100_000;
my $tests  = -10;

sub with {
   use warnings;
   my $i = 0;
   $i = $i + 1         # Undefined check
      for 0..$passes;
   1;
}

sub without {
   no warnings;
   my $i = 0;
   $i = $i + 1         # No undefined check
      for 0..$passes;
   1;
}

cmpthese($tests, {
   with    => \&with,
   without => \&without,
});