| // Copyright 2019 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. | |
| // Flags: --allow-natives-syntax | |
| function foo(a, i) { | |
| a[i] = 1; | |
| return a[i]; | |
| } | |
| class MyArray extends (class C extends Array { | |
| }){}; | |
| o = new MyArray; | |
| %EnsureFeedbackVectorForFunction(foo); | |
| // initialize IC | |
| assertEquals(1, foo(o, 0)); | |
| assertEquals(1, foo(o, 1)); | |
| // Change prototype | |
| o.__proto__.__proto__ = new Int32Array(2); | |
| // Check it still works | |
| assertEquals(undefined, foo(o, 2)); | |
| assertEquals(undefined, foo(o, 2)); |