I'm getting a ton of errors about "Attempt to free non-existent shared string". These errors are coming from LinkExtor as they're all HTML tags.

Attempt to free non-existent shared string 'embed'.
Attempt to free non-existent shared string 'xmp'.
Attempt to free non-existent shared string 'object'.
Attempt to free non-existent shared string 'tr'.
Attempt to free non-existent shared string 'a'.
Attempt to free non-existent shared string 'input'.
Attempt to free non-existent shared string 'area'.
Attempt to free non-existent shared string 'form'.
Attempt to free non-existent shared string 'table'.
Attempt to free non-existent shared string 'frame'.
Attempt to free non-existent shared string 'img'.
Attempt to free non-existent shared string 'body'.
Attempt to free non-existent shared string 'isindex'.
Attempt to free non-existent shared string 'bgsound'.
Attempt to free non-existent shared string 'th'.
Attempt to free non-existent shared string 'base'.
...
Scalars leaked: -32
Bad signature in parser state object at 8359668.
Unbalanced string table refcount: (1) for "tr" during global destructi
+on.
Unbalanced string table refcount: (1) for "isindex" during global dest
+ruction.
Unbalanced string table refcount: (1) for "applet" during global destr
+uction.
Unbalanced string table refcount: (1) for "del" during global destruct
+ion.
Unbalanced string table refcount: (1) for "_parser" during global dest
+ruction.
Unbalanced string table refcount: (1) for "input" during global destru
+ction.
Unbalanced string table refcount: (1) for "table" during global destru
+ction.
Unbalanced string table refcount: (1) for "link" during global destruc
+tion.
...
Scalars leaked: 37
[download]

Any ideas? Relevant code:

    my @retlinks;
    if ($res->is_success) {
        $self->parser->parse($res->content);
        my @links = $self->parser->links;
        my $linkarray;
        foreach $linkarray (@links){
                my @element = @$linkarray;
                my $elt_type = shift @element;

                while(@element){
                        my ($attr_name, $attr_val) = splice(@element, 
+0, 2);
                        if($elt_type eq 'a' && $attr_name eq 'href'){
                                unshift(@retlinks, url($attr_val, $res
+->base)->abs);
                        }

                }


        }
    }
[download]

It all worked fine until I made that method threaded and then everthing went a little crazy. Advice appreciated. Thanks.