Bug #80305 [Com]: Call with the splat operator ignores by reference requirements
| From: | greedy dot ivan at gmail dot com | Date: | Sun, 01 Nov 2020 17:18:54 +0000 |
| Subject: | Bug #80305 [Com]: Call with the splat operator ignores by reference requirements | ||
| References: | 1 | Groups: | php.bugs |
| Request: | Send a blank email to php-bugs+get-230059@lists.php.net to get a copy of this message | ||
Edit report at https://bugs.php.net/bug.php?id=80305&edit=1
ID: 80305
Comment by: greedy dot ivan at gmail dot com
Reported by: greedy dot ivan at gmail dot com
Summary: Call with the splat operator ignores by reference
requirements
Status: Not a bug
Type: Bug
Package: Scripting Engine problem
Operating System: All
PHP Version: 7.4.12
Block user comment: N
Private report: N
New Comment:
This is very strange behavior and should be documented somehow. It doesn't change the argument
itself -- it doesn't replace the value with a reference -- it does change some internal
representation of the argument, which can actually start working with call_user_func_array().
And it's odd that the behavior of the code can be changed simply by calling some kind of
operator with black magic inside.
Previous Comments:
------------------------------------------------------------------------
[2020-11-01 16:32:56] nikic@php.net
The splat call creates a reference in the array, which also allows the following
call_user_func_array() to work.
------------------------------------------------------------------------
[2020-11-01 16:28:52] cmb@php.net
> This is a second issue when using the splat operator modifies
> subsequent calls of call_user_func_array().
Like I said, this is not particularly releated to the splat
operator, though.
------------------------------------------------------------------------
[2020-11-01 16:18:52] greedy dot ivan at gmail dot com
This is a second issue when using the splat operator modifies subsequent calls of
call_user_func_array().
And this is a serious problem, because before this call, it does not change the argument that is not
referenced, but starts doing it after.
------------------------------------------------------------------------
[2020-11-01 16:08:31] cmb@php.net
> Passing arguments using the ... operator ignores requirements as
> to which arguments must be passed by reference.
The splat operator behaves as if the function was called
directly[1]; actually, it is call_user_func_array() which doesn't
behave correctly, but that is already filed as bug #70379.
[1] <https://3v4l.org/Ro4Mn>
------------------------------------------------------------------------
[2020-11-01 15:39:00] greedy dot ivan at gmail dot com
Description:
------------
1. Passing arguments using the ... operator ignores requirements as to which arguments must be
passed by reference.
2. Prevents warnings from subsequent calls that previously threw it (maybe it is some inner cache
issue).
https://3v4l.org/ksVmp
Actually, there is a different behavior for 7.0, 7.3+, and 7.1 - 7.2.
Test script:
---------------
<?php
$foo = function (int &$bar) { $bar++; };
$baz = 0;
$args = [$baz];
call_user_func_array($foo, $args);
echo $args[0];
call_user_func_array($foo, $args);
echo $args[0];
$foo(...$args);
echo $args[0];
call_user_func_array($foo, $args);
echo $args[0];
call_user_func_array($foo, $args);
echo $args[0];
Expected result:
----------------
Warning: Parameter 1 to {closure}() expected to be a reference, value given in /in/ksVmp on line 7
0
Warning: Parameter 1 to {closure}() expected to be a reference, value given in /in/ksVmp on line 10
0
Warning: Parameter 1 to {closure}() expected to be a reference, value given in /in/ksVmp on line 13
0
Warning: Parameter 1 to {closure}() expected to be a reference, value given in /in/ksVmp on line 16
0
Warning: Parameter 1 to {closure}() expected to be a reference, value given in /in/ksVmp on line 19
0
Actual result:
--------------
Warning: Parameter 1 to {closure}() expected to be a reference, value given in /in/ksVmp on line 7
0
Warning: Parameter 1 to {closure}() expected to be a reference, value given in /in/ksVmp on line 10
0123
------------------------------------------------------------------------
--
Edit this bug report at https://bugs.php.net/bug.php?id=80305&edit=1