use strict;
use warnings;
use Test::More tests => 1;

BEGIN {
    eval{ require DynaLoader };
    no warnings 'redefine';
    *DynaLoader::bootstrap = sub { die };
}

eval "use Scalar::Util qw( weaken )";

like( $@, qr/\AWeak references are not implemented/, 
    "Catch unavailable weaken" );