get_declared_interfaces() does not include interfaces extending from other interfaces if script returns early

[tiberiusteng]

Description

The following code:

<?php
print_r(get_declared_interfaces());
print_r(get_declared_classes());
if (interface_exists('a')) {
    return;
}

interface a {}
interface b extends a {}

class c {}
class d extends c {}

Only a appear in get_declared_interfaces(), both c and d appear in get_declared_classes(), perhaps they should be consistent?

We were trying to use if (interface_exists('a')) return; to prevent redeclaring an interface (upgrading legacy code from require_once to SPL autoload), but discovered that adding interface_exists() to old code would prevent them being loaded even when there are no new autoloaded version registered.

Also at first we are assuming get_declared_interfaces(), get_declared_classes() won't include code after them, but seems this is expected behavior.

PHP Version

PHP 8.5.2 (cli) (built: Jan 13 2026 21:40:53) (NTS)
Copyright (c) The PHP Group
Built by Homebrew
Zend Engine v4.5.2, Copyright (c) Zend Technologies
    with Zend OPcache v8.5.2, Copyright (c), by Zend Technologies

Operating System

No response

[iluuu1994]

Hi @tiberiusteng. This is due to early-binding and thus a #wontfix. See https://www.npopov.com/2021/10/20/Early-binding-in-PHP.html for details.