text: // Copyright 2015 the V8 project authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  function Foo() {
    ;
  }
  
  var x = new Foo();
  Foo.prototype = Math.random();
  
  function foo() {
    return x instanceof Foo;
  }
  
  foo();
  TypeError;
  