#41788 [Opn->Bgs]: preg_replace_callback returns NULL instead of input or error

ID: 41788 Updated by: johannes@php.net Reported By: Sjon at hortensius dot net -Status: Open +Status: Bogus Bug Type: Regexps related Operating System: linux 2.6.21.5 PHP Version: 5.2.3 New Comment: Thank you for taking the time to write to us, but this is not a bug. Please double-check the documentation available at http://www.php.net/manual/ and the instructions on how to report a bug at http://bugs.php.net/how-to-report.php See preg_last_error(). Previous Comments: ------------------------------------------------------------------------ [2007-06-24 11:44:45] Sjon at hortensius dot net Description: ------------ The preg_replace_callback manual-entry says: If matches are found, the new subject will be returned, otherwise subject will be returned unchanged. However; I have a testcase where no input is returned; and my callback isn't called either. This seems to be caused by a required pcre.backtrack_limit of 10000000 Shouldn't PHP return the input or an error giving some pointers about this limit being reached? Reproduce code: --------------- <?PHP $input = '{?value==input.value}'; $regexp = '~\{\?(?:\(?!?.+(==)?.+\)?)+\}{\1\/}~sU'; var_dump(preg_replace_callback($regexp, 'callback', $input)); function callback(){ die('called'); } Expected result: ---------------- I expect an error to be raised when pcre.backtrack_limit is reached Actual result: -------------- NULL is var_dumped ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=41788&edit=1