From: tater at potatoe dot com
Operating system: OS X 10.2
PHP version: 4.3.3RC1
PHP Bug Type: Scripting Engine problem
Bug description: extract with EXTR_REFS makes weird references
Description:
------------
If you create an array by assigning its elements the value of a scalar
variable (or, in PHP5, by using array_combine() with an array of keys and
an array built with array_fill() or array_pad()), then extract(array,
EXTR_REFS) will make that scalar into a reference, as well as making all
the array elements references to the same... location? I don't know, they
all end up pointing to the same thing, so that changing any one of them
changes all of them.
This tests the same on the current PHP4 release and the latest CVS PHP5
code.
Reproduce code:
---------------
<?php
function trap()
{
$tick = 0;
$x = array('x1'=>$tick, 'x2'=>$tick, 'x3'=>0, 'x4'=>0);
$y = array('y1'=>$tick, 'y2'=>$tick, 'y3'=>0, 'y4'=>0);
var_dump(get_defined_vars());
foreach ($x as $k => $v)
$$k =& $x[$k];
extract($y, EXTR_REFS);
var_dump(get_defined_vars());
$x1 = 1;
$y1 = 2;
$y3 = 4;
var_dump(get_defined_vars());
$tick = 5;
var_dump(get_defined_vars());
}
trap();
?>
Expected result:
----------------
Changing $y1 should only change it and y['y1'].
Changing $tick should only change $tick.
Actual result:
--------------
Changing $y1 or $tick changes the other as well.
--
Edit bug report at http://bugs.php.net/?id=24630&edit=1
--
Try a CVS snapshot (php4): http://bugs.php.net/fix.php?id=24630&r=trysnapshot4
Try a CVS snapshot (php5): http://bugs.php.net/fix.php?id=24630&r=trysnapshot5
Fixed in CVS: http://bugs.php.net/fix.php?id=24630&r=fixedcvs
Fixed in release: http://bugs.php.net/fix.php?id=24630&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=24630&r=needtrace
Try newer version: http://bugs.php.net/fix.php?id=24630&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=24630&r=support
Expected behavior: http://bugs.php.net/fix.php?id=24630&r=notwrong
Not enough info: http://bugs.php.net/fix.php?id=24630&r=notenoughinfo
Submitted twice: http://bugs.php.net/fix.php?id=24630&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=24630&r=globals
PHP 3 support discontinued: http://bugs.php.net/fix.php?id=24630&r=php3
Daylight Savings: http://bugs.php.net/fix.php?id=24630&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=24630&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=24630&r=gnused
