Hi - which version of php has been used here? My results are different and i wonder why?

```php 8.1

$a = 'foo';

xdebug_debug_zval('a');

$b = $a;

xdebug_debug_zval('a');

a: (interned, is_ref=0)='foo'

a: (interned, is_ref=0)='foo'

```