Bug #76662 [NEW]: Issue sorting when values are equal

From: panin dot alexei at gmail dot com Operating system: OSX and UBUNTU PHP version: 7.0.31 Package: *General Issues Bug Type: Bug Bug description:Issue sorting when values are equal Description: ------------ --- From manual page: http://www.php.net/function.usort --- Even when values are equal, they are mixed. The resulting / sorted array should be identical with initial array, it;s not the case. Test script: --------------- <?php $array = [ ["1", 1], ["2", 1], ["3", 1], ["4", 1], ["5", 1], ["6", 1], ["7", 1], ["8", 1], ["9", 1], ["10", 1], ["11", 1], ["12", 1], ["13", 1], ["14", 1], ["15", 1], ["16", 1], ["17", 1], ["18", 1], ["19", 1], ["20", 1], ["21", 1], ["22", 1], ["23", 1], ["24", 1], ["25", 1], ["26", 1], ["27", 1], ["28", 1], ["29", 1], ["30", 1], ["31", 1], ["32", 1], ["33", 1], ["34", 1], ["35", 1], ["36", 1] ]; usort($array, function($a, $b){ return $a[1] <=> $b[1]; }); print_r($array); Expected result: ---------------- array should bot be altered Actual result: -------------- array is sorted -- Edit bug report at https://bugs.php.net/bug.php?id=76662&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=76662&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=76662&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=76662&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=76662&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=76662&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=76662&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=76662&r=needscript Try newer version: https://bugs.php.net/fix.php?id=76662&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=76662&r=support Expected behavior: https://bugs.php.net/fix.php?id=76662&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=76662&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=76662&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=76662&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=76662&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=76662&r=dst IIS Stability: https://bugs.php.net/fix.php?id=76662&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=76662&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=76662&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=76662&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=76662&r=mysqlcfg