It looks like you're doing too much in XS and not enough in perl. Why can't you have your C-allocating routines just return a numified pointer and let perl do all of its own OO stuff? I also feel like I'm getting lost somewhere in your confused code. I'd really like to point you at Simon Cozen's Embedding and Extending Perl book. Or Damian Conway's Object Oriented Perl.

sub new {
    my ( $class ) = @_;
    my $c_ptr = Foo::Bar::_new_or_whatever();
    return bless \ $c_ptr, $class;
}
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