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<?php $x = 10; $foo = null; $ref = &$foo; do { $ref = array('foo' => 'bar'); $ref = &$ref['foo']; } while (--$x); var_dump($foo);
Output for 5.2.1 - 5.6.28, hhvm-3.10.0 - 3.12.0, 7.0.0 - 7.1.0
array(1) { ["foo"]=> array(1) { ["foo"]=> array(1) { ["foo"]=> array(1) { ["foo"]=> array(1) { ["foo"]=> array(1) { ["foo"]=> array(1) { ["foo"]=> array(1) { ["foo"]=> array(1) { ["foo"]=> array(1) { ["foo"]=> &string(3) "bar" } } } } } } } } } }
Output for 4.3.0 - 5.2.0
array(1) { ["foo"]=> &array(1) { ["foo"]=> &array(1) { ["foo"]=> &array(1) { ["foo"]=> &array(1) { ["foo"]=> &array(1) { ["foo"]=> &array(1) { ["foo"]=> &array(1) { ["foo"]=> &array(1) { ["foo"]=> &array(1) { ["foo"]=> &string(3) "bar" } } } } } } } } } }