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

go to bug id or search bugs for

Bug #31512 wrong expression execution order
Submitted: 2005-01-12 11:57 UTC Modified: 2005-01-12 13:29 UTC
From: dan at yes dot lt Assigned:
Status: Not a bug Package: *General Issues
PHP Version: 4.3.10 OS: any
Private report: No CVE-ID: None
View Developer Edit
 [2005-01-12 11:57 UTC] dan at yes dot lt 
Description:
------------
Arithmetic expression execution returns unexpected results with ++ or -- operators.

Reproduce code:
---------------
$a = 10;   
$c = $a++ + ++$a;
echo "$c\n";

$a = 10;
$c = ++$a + $a++;
echo "$c\n";

Expected result:
----------------
22
22

Actual result:
--------------
22
23 <- ?? Why ??

Patches

Pull Requests

History

AllCommentsChangesGit/SVN commitsRelated reports
 [2005-01-12 13:01 UTC] tony2001@php.net 
Submitted twice.
 [2005-01-12 13:19 UTC] dan at yes dot lt 
<?php

$a = 10;  

$b = &$a;

$a = 10;  
$c = $a++ + ++$a;
echo "$c\n\n"; // 22

$a = 10;
$c = ++$a + $a++;
echo "$c\n\n"; // 23 ??

?>

it works if there is no $b =&$a reference, and fails, if there is that
reference...
 [2005-01-12 13:29 UTC] derick@php.net 
Please do not submit the same bug more than once. An existing
bug report already describes this very problem. Even if you feel
that your issue is somewhat different, the resolution is likely
to be the same. 

Thank you for your interest in PHP.
 
PHP Copyright © 2001-2026 The PHP Group
All rights reserved. 		Last updated: Thu Oct 08 09:00:02 2026 UTC