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run code in 300+ PHP versions simultaneously
<?php function foo(&$var) { $var++; } foo(5); echo $a;
Output for 8.3.0 - 8.3.4
Fatal error: Uncaught Error: foo(): Argument #1 ($var) could not be passed by reference in /in/TR6Di:8 Stack trace: #0 {main} thrown in /in/TR6Di on line 8
Process exited with code 255.
Output for 8.1.23 - 8.1.27, 8.2.10 - 8.2.17
Fatal error: Uncaught Error: foo(): Argument #1 ($var) cannot be passed by reference in /in/TR6Di:8 Stack trace: #0 {main} thrown in /in/TR6Di on line 8
Process exited with code 255.
Output for 7.1.0 - 7.1.12, 7.2.0
Fatal error: Only variables can be passed by reference in /in/TR6Di on line 8
Process exited with code 255.

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