php.net |  support |  documentation |  report a bug |  advanced search |  search howto |  statistics |  random bug |  login

go to bug id or search bugs for

Request #32192 preg_grep does not work with arrays containing references to themselves.
Submitted: 2005-03-04 17:23 UTC Modified: 2019-03-18 16:15 UTC
From: bolk at hitv dot ru Assigned: nikic (profile)
Status: Closed Package: PCRE related
PHP Version: 5.0.3 OS: Linux RH 9 and Windows XP
Private report: No CVE-ID: None
View Add Comment Developer Edit
Welcome back! If you're the original bug submitter, here's where you can edit the bug or add additional notes.
If this is not your bug, you can add a comment by following this link.
If this is your bug, but you forgot your password, you can retrieve your password here.
Password:
Status:
Package:
Bug Type:
Summary:
From: bolk at hitv dot ru
New email:
PHP Version: OS:

 

 [2005-03-04 17:23 UTC] bolk at hitv dot ru 
Description:
------------
preg_grep damage GLOBALS

Bug in PHP 4.3.10 and 5.0.3

Reproduce code:
---------------
<?
	preg_grep('/^T_/', $GLOBALS);
	var_dump($GLOBALS);
?>


Expected result:
----------------
array(16) {
  ["argv"]=>
  array(1) {
    [0]=>
    string(5) "a.php"
  }
  ["argc"]=>
  int(1)
  ["HTTP_POST_VARS"]=>
  array(0) {
  }
  ["_POST"]=>
  array(0) {
  }
  ["HTTP_GET_VARS"]=>
  array(0) {
  }
  ["_GET"]=>
  array(0) {
  }
  ["HTTP_COOKIE_VARS"]=>
  array(0) {
  }
  ["_COOKIE"]=>
  array(0) {
  }
  ["HTTP_SERVER_VARS"]=>


etceteras

Actual result:
--------------
string(5) "Array"

Patches

Add a Patch

Pull Requests

Add a Pull Request

History

AllCommentsChangesGit/SVN commitsRelated reports
 [2005-03-04 18:22 UTC] tony2001@php.net 
That's because $GLOBALS contains reference to itself.
So I'd call this kinda expected behaviour.
See this code:
<?php
$a = Array();
$a[] = &$a; 

preg_grep('/^T_/', $a);
var_dump($a);
?>
 [2005-03-04 18:36 UTC] bolk at hitv dot ru 
Is it "expected behaviour" too? I think no.

<?
	$b = array(1,2,3);

	$a = array();
	$a[] = &$b;

	preg_grep('/^T_/', $a);

	var_dump($a);
	var_dump($b);
?>

array(1) {
  [0]=>
  &string(5) "Array"
}
string(5) "Array"
 [2005-03-04 18:37 UTC] plintus at smtp dot ru 
Tony, if a bug occurs in some other situations, it's still a bug. However, Microsoft can use this trick: "Bugs are expected behaviour in Windows" :-)
 [2005-03-04 18:56 UTC] tony2001@php.net 
bolk:
yup, this is the very same behaviour.
all elements of the target array get converted to strings, that's what you see.

plintus:
propose your own solution instead of useless comments?
recursive references should be carefully used and current situation looks like a user fault to me.
 [2005-03-04 19:01 UTC] bolk at hitv dot ru 
I belive this situation must be detected. I think it is a bug. preg_grep() should not change its agruments.
 [2005-03-04 19:08 UTC] bolk at hitv dot ru 
I see that the zend_print_zval_r_ex() detects recursive references.
 [2005-03-04 19:18 UTC] bolk at hitv dot ru 
Why not introduce a function that converts refs to non-refs in array? Say, array_flatten ($array) or something?
 [2016-12-30 22:54 UTC] cmb@php.net
-Package: Feature/Change Request +Package: PCRE related
 [2019-03-18 16:15 UTC] nikic@php.net
-Status: Open +Status: Closed -Assigned To: +Assigned To: nikic
 [2019-03-18 16:15 UTC] nikic@php.net 
Looks like this has been fixed a long time ago: https://3v4l.org/0f1ba
 
PHP Copyright © 2001-2024 The PHP Group
All rights reserved. 		Last updated: Thu Apr 25 09:01:29 2024 UTC