Bug #53863 [NEW]: scalar reference of array element has unintended side effects

From: Operating system: CentOS 5.5 PHP version: 5.3.5 Package: Variables related Bug Type: Bug Bug description:scalar reference of array element has unintended side effects Description: ------------ Adding a scalar reference to an array element changes array assignment behavior. In a regular array assignment, elements are all copied by value. But if a scalar reference has been made to an array element, that element is copied by reference in a subsequent array assignment. The code looks exactly the same, so the behavior shouldn't change just because there's a reference floating out there somewhere. Test script: --------------- <?php $arr1 = array(1); echo "\nbefore:\n"; echo "\$arr1[0] == {$arr1[0]}\n"; $arr2 = $arr1; $arr2[0]++; echo "\nafter:\n"; echo "\$arr1[0] == {$arr1[0]}\n"; echo "\$arr2[0] == {$arr2[0]}\n"; $arr3 = array(1); $a =& $arr3[0]; echo "\nbefore:\n"; echo "\$a == $a\n"; echo "\$arr3[0] == {$arr3[0]}\n"; $arr4 = $arr3; $arr4[0]++; echo "\nafter:\n"; echo "\$a == $a\n"; echo "\$arr3[0] == {$arr3[0]}\n"; echo "\$arr4[0] == {$arr4[0]}\n"; Expected result: ---------------- before: $arr1[0] == 1 after: $arr1[0] == 1 $arr2[0] == 2 before: $a == 1 $arr3[0] == 1 after: $a == 1 $arr3[0] == 1 $arr4[0] == 2 Actual result: -------------- before: $arr1[0] == 1 after: $arr1[0] == 1 $arr2[0] == 2 before: $a == 1 $arr3[0] == 1 after: $a == 2 $arr3[0] == 2 $arr4[0] == 2 -- Edit bug report at http://bugs.php.net/bug.php?id=53863&edit=1 -- Try a snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=53863&r=trysnapshot52 Try a snapshot (PHP 5.3): http://bugs.php.net/fix.php?id=53863&r=trysnapshot53 Try a snapshot (trunk): http://bugs.php.net/fix.php?id=53863&r=trysnapshottrunk Fixed in SVN: http://bugs.php.net/fix.php?id=53863&r=fixed Fixed in SVN and need be documented: http://bugs.php.net/fix.php?id=53863&r=needdocs Fixed in release: http://bugs.php.net/fix.php?id=53863&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=53863&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=53863&r=needscript Try newer version: http://bugs.php.net/fix.php?id=53863&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=53863&r=support Expected behavior: http://bugs.php.net/fix.php?id=53863&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=53863&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=53863&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=53863&r=globals PHP 4 support discontinued: http://bugs.php.net/fix.php?id=53863&r=php4 Daylight Savings: http://bugs.php.net/fix.php?id=53863&r=dst IIS Stability: http://bugs.php.net/fix.php?id=53863&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=53863&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=53863&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=53863&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=53863&r=mysqlcfg