function f() {} var fn = f; for (var i = 0; i < 100000; ++i) { fn = fn.bind(); // Ensure we don't fallback to @@hasInstance from %FunctionPrototype%. Object.defineProperty(fn, Symbol.hasInstance, { value: undefined, writable: true, enumerable: true, writable: true }); // Prevent generating overlong names of the form "bound bound bound [...] f". Object.defineProperty(fn, "name", { value: "", writable: true, enumerable: true, writable: true }); } assertThrowsInstanceOf( () => ({}) instanceof fn, Error, "detect runaway recursion delegating instanceof to bound function target"); reportCompare(0, 0);