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
