var ab = new ArrayBuffer(5);
var p = new Proxy(ab, {});
var ps = Object.getOwnPropertyDescriptor(Object.prototype, "__proto__").set;
var threw = 0;
try {
    ps.call(p, {});
} catch(ex) {
    threw = 1;
}

reportCompare(1, threw, "Setting __proto__ on a proxy to an ArrayBuffer must throw.");