    public static function getErrorMessage ($pcreConstant) {
        $definedConstants = get_defined_constants (true);
        $pcreConstantsByErrorCodes = array_flip ($definedConstants['pcre']);
        return isset ($pcreConstantsByErrorCodes[$pcreConstant]) ?
            $pcreConstantsByErrorCodes[$pcreConstant] : '';
    }
The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.