Thanks for the short answer. I did just that, and it worked beautifully.

Final code example:
package Top;

sub new {
  my $class = shift;
  my $s = bless { }, $class;
  $s->{bottom} = Bottom->new( $s );
  return $s;
}

#=====================================

package Bottom;
use Scalar::Util 'weaken';

sub new {
  my ($class, $top) = @_;
  my $s = bless { top => $top }, $class;
  weaken($s->{top});
  return $s;
}

#=====================================

package main;

use strict;
use warnings 'all';
use Devel::Cycle;

my $top = Top->new();
my $bottom = $top->{bottom} or die "NO BOTTOM!";
$top = $bottom->{top} or die "NO TOP!";

find_cycle( $top );
find_cycle( $bottom );

[download]
Expected output: (nothing)

UPDATE: - Now it burns through 52Mb RAM in 26 seconds. Not sure if that's good or bad. I would expect Perl to recycle the RAM. Is that expectation wrong? Sure, 52Mb is better than the original number of 200Mb, but I would like to see no leakage at all.

Is it possible to do this without leaking memory?

In reply to Re^2: Memory leaks and circular references by jdrago_999
in thread Memory leaks and circular references by jdrago_999

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