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<?php function foo(&$arg) { var_dump($arg); } $a = 'bar'; $b =& $a; call_user_func_array('foo', [$b]); call_user_func_array('foo', [&$a]);
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Warning: foo(): Argument #1 ($arg) must be passed by reference, value given in /in/tDBN8 on line 10 string(3) "bar" string(3) "bar"
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
Warning: Parameter 1 to foo() expected to be a reference, value given in /in/tDBN8 on line 10 string(3) "bar" string(3) "bar"
Output for 7.0.0 - 7.0.20
Warning: Parameter 1 to foo() expected to be a reference, value given in /in/tDBN8 on line 10 string(3) "bar"
Output for 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28
string(3) "bar" string(3) "bar"
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/tDBN8 on line 10
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected '[' in /in/tDBN8 on line 10
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/tDBN8 on line 10
Process exited with code 255.
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