package Logger;

sub new {
    my $self = ...
    ...

    $SIG{__DIE__} = sub {
        my $msg = shift;
        $self->add($msg);
        die $msg;
    };

    return $self;
}

##</code><code>##

package Logger;
our @instances;

sub new {
    my $self = ...;
    ...
    
    push @instances, $self;
    return $self;
}

$SIG{__DIE__} = sub {
    my $msg = shift;
    $_->add($msg) for @instances;
}