#43484 [Opn->Bgs]: call_user_func_array(): questionable pass-by-val/pass-by-ref behaviour.

ID: 43484 Updated by: johannes@php.net Reported By: robin_fernandes at uk dot ibm dot com -Status: Open +Status: Bogus Bug Type: Scripting Engine problem Operating System: Windows PHP Version: 5.3CVS-2007-12-03 (snap) New Comment: Thank you for taking the time to write to us, but this is not a bug. Please double-check the documentation available at http://www.php.net/manual/ and the instructions on how to report a bug at http://bugs.php.net/how-to-report.php $args = array('original.a', 'original.b'); This puts a copy of the value 'original.a' into that array. Previous Comments: ------------------------------------------------------------------------ [2007-12-03 14:09:12] robin_fernandes at uk dot ibm dot com Description: ------------ This issue was originally raised as documentation bug 43079. Raising as Scripting Engine problem as suggested by vrana at php dot net. The pass-by-value/pass-by-ref behaviour of call_user_func_array() is not intuitive (see the user contributed notes on the documentation page: http://php.net/call_user_func_array ). It appears that the way in which an argument is passed depends not on the target function signature, but rather on whether its entry in $param_arr is referenced or not. Specifically, it is possible to force an argument to be passed by reference to a function which expects a pass-by-value argument, even with call time pass by reference DISABLED in php.ini. Reproduced on php5.3 and php6 snaps on Windows. Reproduce code: --------------- <?php function byRef(&$a, &$b) { $a = 'changed.a'; $b = 'changed.b'; } function byVal($a, $b) { $a = 'changed.a'; $b = 'changed.b'; } //Currently, this forces a pass-by-ref function to take args by val: $args = array('original.a', 'original.b'); call_user_func_array('byRef', $args); var_dump($args); //Currently, this forces a pass-by-val function to take 1 arg by ref. //This works even with call-time pass-by-ref DISABLED in php.ini. $args = array('original.a', 'original.b'); $ref = &$args[0]; call_user_func_array('byVal', $args); var_dump($args); ?> Expected result: ---------------- array(2) { [0]=> string(9) "changed.a" [1]=> string(9) "changed.b" } array(2) { [0]=> &string(10) "original.a" [1]=> string(10) "original.b" } Actual result: -------------- array(2) { [0]=> string(10) "original.a" [1]=> string(10) "original.b" } array(2) { [0]=> &string(9) "changed.a" [1]=> string(10) "original.b" } ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=43484&edit=1