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<?php function f($a) { if ($a > 0) { $b = f($a-1); } return $b; } echo f(1);
Output for 8.0.0alpha1 - beta1
Warning: Undefined variable $b in /in/4m0HZ on line 6
Output for 5.5.0 - 5.5.35, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 7.2.0 - 7.2.32, 7.3.0 - 7.3.20, 7.4.0 - 7.4.8
Notice: Undefined variable: b in /in/4m0HZ on line 6
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45