Bug #79996 [Com]: Reference trouble in closure

Edit report at https://bugs.php.net/bug.php?id=79996&edit=1 ID: 79996 Comment by: tropicano at ukr dot net Reported by: tropicano at ukr dot net Summary: Reference trouble in closure Status: Not a bug Type: Bug Package: *General Issues Operating System: Windows 10 PHP Version: 7.4.9 Block user comment: N Private report: N New Comment: Thanks! Previous Comments: ------------------------------------------------------------------------ [2020-08-19 13:40:51] danack@php.net Pretty sure your code is the equivalent of: $x = 0; $data = 1; $foo = &$data; $foo = &$x; $foo = 40; echo $data; When a value is written to $foo, it is poiting to where $x is stored. Which means that $data still has the original value it had, and was never modified. ------------------------------------------------------------------------ [2020-08-19 13:15:00] tropicano at ukr dot net I known that it possible not good construction, my code is very hard to show bug. But $data must be assigned value "2" or show notice/warning/error. ------------------------------------------------------------------------ [2020-08-19 12:42:28] danack@php.net Pretty sure your code is working correctly, just not as you expect it to. $data =& $x; That line makes $data be a reference to the value stored in $x which was captured by value in use ($x) . It breaks the reference to the value stored in $data = 1 I'd pretty strongly recommend not using references like this. Either use objects with clearer semantics, or just pass in and return values. Trying to manage state with references like this is confusing, as you're finding out. ------------------------------------------------------------------------ [2020-08-19 12:30:46] tropicano at ukr dot net Description: ------------ Not correct result in closure function. Please review and fix it. Test script: --------------- $x = 0; function main($func, $func2) { return $func($func2); } function callback_main($func3) { $data = 1; $func3($data); return $data; } echo main('callback_main', function (&$data) use ($x) { $data =& $x; $data = 2; } ); Expected result: ---------------- echo is: 1 Actual result: -------------- must be: 2 ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=79996&edit=1