3v4l.org

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<?php function foo(&$var){ echo $var++; } var_dump(foo(5)); ?>
Output for 8.3.0 - 8.3.6
Fatal error: Uncaught Error: foo(): Argument #1 ($var) could not be passed by reference in /in/dVDFI:5 Stack trace: #0 {main} thrown in /in/dVDFI on line 5
Process exited with code 255.
Output for 8.1.23 - 8.1.28, 8.2.10 - 8.2.18
Fatal error: Uncaught Error: foo(): Argument #1 ($var) cannot be passed by reference in /in/dVDFI:5 Stack trace: #0 {main} thrown in /in/dVDFI on line 5
Process exited with code 255.
Output for 5.3.0 - 5.3.22, 5.3.24, 5.4.0 - 5.4.12, 5.4.14
Fatal error: Only variables can be passed by reference in dVDFI on line 5
Process exited with code 255.
Output for 5.3.23, 5.4.13
Fatal error: Only variables can be passed by reference in /in/KNZFL on line 5
Process exited with code 255.

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