Description

The following code:

<?php
var_dump(
    $_SERVER['FOO'] ?? 'unset', 
    $_ENV['FOO'] ?? 'unset', 
    getenv('FOO')
);

When run with variables_order = "EGPCS" and FOO=GüИter传 set in the environment variables in Windows (or using $env:FOO = 'GüИter传' in PowerShell before executing the test file above).

Resulted in this output:

string(7) "G?ter?"
string(7) "G?ter?"
string(11) "GüИter传"

But I expected this output instead:

string(11) "GüИter传"
string(11) "GüИter传"
string(11) "GüИter传"

Doing the same in WSL/Ubuntu seems to yield the correct result, so I assume it's Windows specific.

Regarding PHP version, it appears all versions <7.2 fail completely, with even getenv() returning string(7) "G?ter?" or string(7) "Gⁿ?ter?" for 5.x. From PHP 7.2 onwards I get the behavior described above.

PHP Version

8.0.13

Operating System

Windows 10