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<?php function byRef(&$r) { $r += 1; } $a = 1; byRef($r = $a); var_dump($r);
Output for 8.3.0 - 8.3.6
Fatal error: Uncaught Error: byRef(): Argument #1 ($r) could not be passed by reference in /in/I9iWF:6 Stack trace: #0 {main} thrown in /in/I9iWF on line 6
Process exited with code 255.
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18
Fatal error: Uncaught Error: byRef(): Argument #1 ($r) cannot be passed by reference in /in/I9iWF:6 Stack trace: #0 {main} thrown in /in/I9iWF on line 6
Process exited with code 255.
Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33
Notice: Only variables should be passed by reference in /in/I9iWF on line 6 int(1)
Output for 7.3.32 - 7.3.33
int(1)
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.40
Strict Standards: Only variables should be passed by reference in /in/I9iWF on line 6 int(1)

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