From: mcorne at yahoo dot com
Operating system: Windows XP
PHP version: 5.2.3
PHP Bug Type: Scripting Engine problem
Bug description: debug_backtrace messes up with references
Description:
------------
error #1: debug_backtrace() does not report the original value of a
variable passed by reference even if it is called before the variable is
modified.
error #2: debug_backtrace() messes up with the content of an array used to
store debug_backtrace() results from subsequent calls to the same
function.
Reproduce code:
---------------
<?php
function trace()
{
global $trace;
$trace[] = debug_backtrace();
}
function foo(&$pos)
{
trace();
$pos++;
}
$pos = 0;
foo($pos);
echo "error #1\n----------\n";
var_export($trace);
echo "\n\nerror #2\n----------\n";
foo($pos);
var_export($trace);
?>
Expected result:
----------------
error #1
----------
array (
0 =>
array (
0 =>
array (
'file' =>
'D:\\Data\\dev\\i18n-unicodnorm\\trunk\\I18N\\tests\\bug.php',
'line' => 11,
'function' => 'trace',
'args' =>
array (
),
),
1 =>
array (
'file' =>
'D:\\Data\\dev\\i18n-unicodnorm\\trunk\\I18N\\tests\\bug.php',
'line' => 16,
'function' => 'foo',
'args' =>
array (
0 => 0,
),
),
),
)
error #2
----------
array (
0 =>
array (
0 =>
array (
'file' =>
'D:\\Data\\dev\\i18n-unicodnorm\\trunk\\I18N\\tests\\bug.php',
'line' => 11,
'function' => 'trace',
'args' =>
array (
),
),
1 =>
array (
'file' =>
'D:\\Data\\dev\\i18n-unicodnorm\\trunk\\I18N\\tests\\bug.php',
'line' => 16,
'function' => 'foo',
'args' =>
array (
0 => 0,
),
),
),
1 =>
array (
0 =>
array (
'file' =>
'D:\\Data\\dev\\i18n-unicodnorm\\trunk\\I18N\\tests\\bug.php',
'line' => 11,
'function' => 'trace',
'args' =>
array (
),
),
1 =>
array (
'file' =>
'D:\\Data\\dev\\i18n-unicodnorm\\trunk\\I18N\\tests\\bug.php',
'line' => 20,
'function' => 'foo',
'args' =>
array (
0 => 1,
),
),
),
)
Actual result:
--------------
error #1
----------
array (
0 =>
array (
0 =>
array (
'file' =>
'D:\\Data\\dev\\i18n-unicodnorm\\trunk\\I18N\\tests\\bug.php',
'line' => 11,
'function' => 'trace',
'args' =>
array (
),
),
1 =>
array (
'file' =>
'D:\\Data\\dev\\i18n-unicodnorm\\trunk\\I18N\\tests\\bug.php',
'line' => 16,
'function' => 'foo',
'args' =>
array (
0 => 1,
),
),
),
)
error #2
----------
array (
0 =>
array (
0 =>
array (
'file' =>
'D:\\Data\\dev\\i18n-unicodnorm\\trunk\\I18N\\tests\\bug.php',
'line' => 11,
'function' => 'trace',
'args' =>
array (
),
),
1 =>
array (
'file' =>
'D:\\Data\\dev\\i18n-unicodnorm\\trunk\\I18N\\tests\\bug.php',
'line' => 16,
'function' => 'foo',
'args' =>
array (
0 => 2,
),
),
),
1 =>
array (
0 =>
array (
'file' =>
'D:\\Data\\dev\\i18n-unicodnorm\\trunk\\I18N\\tests\\bug.php',
'line' => 11,
'function' => 'trace',
'args' =>
array (
),
),
1 =>
array (
'file' =>
'D:\\Data\\dev\\i18n-unicodnorm\\trunk\\I18N\\tests\\bug.php',
'line' => 20,
'function' => 'foo',
'args' =>
array (
0 => 2,
),
),
),
--
Edit bug report at http://bugs.php.net/?id=42058&edit=1
--
Try a CVS snapshot (PHP 4.4): http://bugs.php.net/fix.php?id=42058&r=trysnapshot44
Try a CVS snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=42058&r=trysnapshot52
Try a CVS snapshot (PHP 6.0): http://bugs.php.net/fix.php?id=42058&r=trysnapshot60
Fixed in CVS: http://bugs.php.net/fix.php?id=42058&r=fixedcvs
Fixed in release: http://bugs.php.net/fix.php?id=42058&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=42058&r=needtrace
Need Reproduce Script: http://bugs.php.net/fix.php?id=42058&r=needscript
Try newer version: http://bugs.php.net/fix.php?id=42058&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=42058&r=support
Expected behavior: http://bugs.php.net/fix.php?id=42058&r=notwrong
Not enough info: http://bugs.php.net/fix.php?id=42058&r=notenoughinfo
Submitted twice: http://bugs.php.net/fix.php?id=42058&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=42058&r=globals
PHP 3 support discontinued: http://bugs.php.net/fix.php?id=42058&r=php3
Daylight Savings: http://bugs.php.net/fix.php?id=42058&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=42058&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=42058&r=gnused
Floating point limitations: http://bugs.php.net/fix.php?id=42058&r=float
No Zend Extensions: http://bugs.php.net/fix.php?id=42058&r=nozend
MySQL Configuration Error: http://bugs.php.net/fix.php?id=42058&r=mysqlcfg