[php-src] Issue #7917: preg_match and preg_match_all both do not set $matches on regex fail, leaving as it was set prior to call

Issue: https://github.com/php/php-src/issues/7917 Comment Author: iluuu1994 The best behavior for PHP would probably be to throw an exception so your program never accesses $matches when providing an invalid regex in the first place. That's something worth discussing for PHP 9.