1--TEST--
2Instanceof checks in VERIFY_RETURN_TYPE optimization may deal with unlinked classes
3--EXTENSIONS--
4opcache
5--FILE--
6<?php
7interface foo { }
8
9interface biz {}
10
11class qux implements foo {
12    public function bar(): biz {
13        $x = $this;
14        return $x;
15    }
16}
17
18?>
19===DONE===
20--EXPECT--
21===DONE===
22