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run code in 500+ PHP versions simultaneously
<?php $foo = function (int &$bar) { $bar++; }; $baz = 0; $args = [$baz]; call_user_func_array($foo, $args); echo $args[0]; call_user_func_array($foo, $args); echo $args[0]; $foo($args[0]); echo $args[0]; call_user_func_array($foo, $args); echo $args[0]; call_user_func_array($foo, $args); echo $args[0];
Output for 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
Warning: {closure:/in/Ro4Mn:3}(): Argument #1 ($bar) must be passed by reference, value given in /in/Ro4Mn on line 7 0 Warning: {closure:/in/Ro4Mn:3}(): Argument #1 ($bar) must be passed by reference, value given in /in/Ro4Mn on line 10 0123
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30
Warning: {closure}(): Argument #1 ($bar) must be passed by reference, value given in /in/Ro4Mn on line 7 0 Warning: {closure}(): Argument #1 ($bar) must be passed by reference, value given in /in/Ro4Mn on line 10 0123
Output for 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
Warning: Parameter 1 to {closure}() expected to be a reference, value given in /in/Ro4Mn on line 7 0 Warning: Parameter 1 to {closure}() expected to be a reference, value given in /in/Ro4Mn on line 10 0123
Output for 7.2.0 - 7.2.34
Warning: Parameter 1 to {closure}() expected to be a reference, value given in /in/Ro4Mn on line 7 0 Warning: Parameter 1 to {closure}() expected to be a reference, value given in /in/Ro4Mn on line 10 01 Warning: Parameter 1 to {closure}() expected to be a reference, value given in /in/Ro4Mn on line 16 1 Warning: Parameter 1 to {closure}() expected to be a reference, value given in /in/Ro4Mn on line 19 1

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