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<?php function by_ref(&$ref) {} by_ref(substr("foo", 1));
Output for 8.4.1 - 8.4.12
Fatal error: Uncaught Error: by_ref(): Argument #1 ($ref) could not be passed by reference in /in/5AIrb:4 Stack trace: #0 {main} thrown in /in/5AIrb on line 4
Process exited with code 255.
Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25
Notice: Only variables should be passed by reference in /in/5AIrb on line 4
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40
Strict Standards: Only variables should be passed by reference in /in/5AIrb on line 4

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