From: cdragon at draconic dot com
Operating system: Windows 2000 Server
PHP version: 4CVS-2003-09-30 (stable)
PHP Bug Type: Variables related
Bug description: extract($GLOBALS, EXTR_REFS); can corrupt the $GLOBALS array.
Description:
------------
Using extract($GLOBALS, EXTR_REFS); can cause the left hand side of two
globals set "by-value" equal to one-another to become corrupted in the
$GLOBALS array. Hard to explain in English, but easier to see in the code
below.
Reproduce code:
---------------
$sortColumn = "Affinity";
// Using "$lastSortColumn = substr($sortColumn, 0);" fixes the bug
$lastSortColumn = $sortColumn;
print "sort=" . $GLOBALS['sortColumn'] . " lastsort=" .
$GLOBALS['lastSortColumn'] . "<p>";
extractGlobs();
print "sort=" . $GLOBALS['sortColumn'] . " lastsort=" .
$GLOBALS['lastSortColumn'] . "<p>";
function extractGlobs()
{
// Commenting out the line below fixes the bug. So does not using the
EXTR_REFS flag.
extract($GLOBALS, EXTR_REFS);
}
Expected result:
----------------
sort=Affinity lastsort=Affinity
sort=Affinity lastsort=Affinity
Actual result:
--------------
sort=Affinity lastsort=Affinity
sort=Affinity lastsort=
or, randomly, you get an access violation instead:
PHP has encountered an Access Violation at 02CFF32F
(the 02CFF32F is variable)
--
Edit bug report at http://bugs.php.net/?id=25708&edit=1
--
Try a CVS snapshot (php4): http://bugs.php.net/fix.php?id=25708&r=trysnapshot4
Try a CVS snapshot (php5): http://bugs.php.net/fix.php?id=25708&r=trysnapshot5
Fixed in CVS: http://bugs.php.net/fix.php?id=25708&r=fixedcvs
Fixed in release: http://bugs.php.net/fix.php?id=25708&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=25708&r=needtrace
Try newer version: http://bugs.php.net/fix.php?id=25708&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=25708&r=support
Expected behavior: http://bugs.php.net/fix.php?id=25708&r=notwrong
Not enough info: http://bugs.php.net/fix.php?id=25708&r=notenoughinfo
Submitted twice: http://bugs.php.net/fix.php?id=25708&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=25708&r=globals
PHP 3 support discontinued: http://bugs.php.net/fix.php?id=25708&r=php3
Daylight Savings: http://bugs.php.net/fix.php?id=25708&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=25708&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=25708&r=gnused
Floating point limitations: http://bugs.php.net/fix.php?id=25708&r=float
