From: crisp at tweakers dot net Operating system: all PHP version: 4.4.2 PHP Bug Type: PCRE related Bug description: preg_match_all incorrect due to backtrack length limit?
Description: ------------ It seems that when PCRE needs to backtrack more than 20 characters in order to evaluate an OR'ed expression the results of a preg_match_all are incorrect/incomplete. See below code as an example. Reproduce code: --------------- $foo = 'foo# bar# abcdefghijklmnopqrst bla#'; echo '$foo = ', $foo, "\n"; preg_match_all('/([a-y]|z)+#/', $foo, $matches1); preg_match_all('/([a-y]+|z)+#/', $foo, $matches2); print_r($matches1[0]); print_r($matches2[0]); $foo = 'foo# bar# abcdefghijklmnopqrstu bla#'; echo '$foo = ', $foo, "\n"; preg_match_all('/([a-y]|z)+#/', $foo, $matches1); preg_match_all('/([a-y]+|z)+#/', $foo, $matches2); print_r($matches1[0]); print_r($matches2[0]); Expected result: ---------------- both expressions for both strings should give the following output: Array ( [0] => foo# [1] => bar# [2] => bla# ) Actual result: -------------- The last expression gives the following output on the last string: Array ( [0] => foo# [1] => bar# ) The last match on bla# is missing in the result for the preg_match_all -- Edit bug report at http://bugs.php.net/?id=36983&edit=1 -- Try a CVS snapshot (PHP 4.4): http://bugs.php.net/fix.php?id=36983&r=trysnapshot44 Try a CVS snapshot (PHP 5.1): http://bugs.php.net/fix.php?id=36983&r=trysnapshot51 Try a CVS snapshot (PHP 6.0): http://bugs.php.net/fix.php?id=36983&r=trysnapshot60 Fixed in CVS: http://bugs.php.net/fix.php?id=36983&r=fixedcvs Fixed in release: http://bugs.php.net/fix.php?id=36983&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=36983&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=36983&r=needscript Try newer version: http://bugs.php.net/fix.php?id=36983&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=36983&r=support Expected behavior: http://bugs.php.net/fix.php?id=36983&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=36983&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=36983&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=36983&r=globals PHP 3 support discontinued: http://bugs.php.net/fix.php?id=36983&r=php3 Daylight Savings: http://bugs.php.net/fix.php?id=36983&r=dst IIS Stability: http://bugs.php.net/fix.php?id=36983&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=36983&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=36983&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=36983&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=36983&r=mysqlcfg