message: fixed CID#1447618
diff: @@ -482,7 +482,7 @@ static sw_inline int php_swoole_is_callable(zval *callback TSRMLS_DC)
  return SW_FALSE;
  }
  char *func_name = NULL;
  - if (sw_zend_is_callable(callback, 0, &func_name TSRMLS_CC) < 0)
  + if (!sw_zend_is_callable(callback, 0, &func_name TSRMLS_CC))
  {
  swoole_php_fatal_error(E_WARNING, "Function '%s' is not callable", func_name);
  efree(func_name);
  