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<?php $obj = new stdClass; $obj->expr = new stdClass; $a = $obj; while ($a->expr instanceof stdClass) { $a->expr->expr = 'test'; $a = $a->expr; } var_dump($obj); var_dump($obj === $a);
Output for 8.0.1 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
object(stdClass)#1 (1) { ["expr"]=> object(stdClass)#2 (1) { ["expr"]=> string(4) "test" } } bool(false)

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