--TEST-- Bug #71334: Cannot access array keys while uksort() --FILE-- [1], '-' => [2], 'bar-test' => [3] ]; private function _mySort($x, $y) { if (!isset($this->a[$x])) { throw new Exception('Missing X: "' . $x . '"'); } if (!isset($this->a[$y])) { throw new Exception('Missing Y: "' . $y . '"'); } return $x <=> $y; } public function __construct() { uksort($this->a, [$this, '_mySort']); } } new myClass(); echo "Done"; ?> --EXPECT-- Done