3v4l.org

run code in 300+ PHP versions simultaneously
<?php // using debug_backtrace(); function a($inicial) { echo "Inicial => ", $inicial; $total = ++$inicial; b($total); } function b($total) { echo "Total => ", $total; print_r(debug_backtrace()); } a(1);
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Inicial => 1Total => 2Array ( [0] => Array ( [file] => /in/luFqE [line] => 8 [function] => b [args] => Array ( [0] => 2 ) ) [1] => Array ( [file] => /in/luFqE [line] => 17 [function] => a [args] => Array ( [0] => 2 ) ) )
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.35, 5.6.0 - 5.6.28
Inicial => 1Total => 2Array ( [0] => Array ( [file] => /in/luFqE [line] => 8 [function] => b [args] => Array ( [0] => 2 ) ) [1] => Array ( [file] => /in/luFqE [line] => 17 [function] => a [args] => Array ( [0] => 1 ) ) )

preferences:
264 ms | 404 KiB | 388 Q