Description:
------------
When a constant is defined in an interface with a value of another class or interface constant, a fatal error is triggered:

Fatal error: Cannot inherit previously-inherited or override constant FOO from interface IMyInterface in Bar.php on line 3

To reproduce this following conditions must be met (took me 2 days to figure this out):
- the constant value must be defined as another class/interface constant
- classes and interfaces must be autoloaded on demand
- two classes must implement the interface
- one class must inherit the other one
- the super class must be instantiated before the sub class

Seems like this is related to bug #33732 and bug #38286 but is still not fixed.

Test script:
---------------

File IMyInterface.php:
----------------------
<?php
interface IMyInterface
{
    // Use any class or interface constant as value of FOO.
    // I'll just use some constant available out of the box, to keep it simple:
    const FOO = FilesystemIterator::CURRENT_AS_PATHNAME;
}


File Foo.php:
----------------------
<?php
class Foo implements IMyInterface {}


File Bar.php:
----------------------
<?php
class Bar extends Foo implements IMyInterface {}


File index.php:
----------------------
<?php
date_default_timezone_set('Europe/Warsaw');
spl_autoload_register(function($cname){
    if ( class_exists($cname, false) || interface_exists($cname, false) ) {
        return;
    }
    require_once "{$cname}.php";
});

// Foo is super-class for Bar.
// uncomment below line to trigger the error:
$F = new Foo();

// this should run without errors at any time, but if Foo is instantiated
// prior to this line, then the error is triggered:
$B = new Bar();

Expected result:
----------------
No errors, the code is correct.

Actual result:
--------------
Fatal error: Cannot inherit previously-inherited or override constant FOO from interface IMyInterface in Bar.php on line 3