v8/test/mjsunit/compiler/regress-4389-4.js

// 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.

// Flags: --allow-natives-syntax

function foo(x) { Math.round(x); }
foo(1);
foo(2);
%OptimizeFunctionOnNextCall(foo);
assertThrows(function() { foo(Symbol()) }, TypeError);