3v4l.org

run code in 300+ PHP versions simultaneously
<?php error_reporting(~0); function foo(&$a) {} function bar() { return 1; } function &baz() { $a = 1; return $a; } echo "bar\n"; foo(bar()); // STRICT echo "baz\n"; foo(baz()); // Not strict echo "scalar\n"; foo(1);
Output for 8.3.0 - 8.3.4
bar Notice: Only variables should be passed by reference in /in/lPf5b on line 9 baz scalar Fatal error: Uncaught Error: foo(): Argument #1 ($a) could not be passed by reference in /in/lPf5b:13 Stack trace: #0 {main} thrown in /in/lPf5b on line 13
Process exited with code 255.
Output for 8.1.23 - 8.1.27, 8.2.10 - 8.2.17
bar Notice: Only variables should be passed by reference in /in/lPf5b on line 9 baz scalar Fatal error: Uncaught Error: foo(): Argument #1 ($a) cannot be passed by reference in /in/lPf5b:13 Stack trace: #0 {main} thrown in /in/lPf5b on line 13
Process exited with code 255.
Output for 5.3.0 - 5.3.28, 5.4.0 - 5.4.31
Fatal error: Only variables can be passed by reference in /in/lPf5b on line 13
Process exited with code 255.

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