error[E0658]: `format_args_nl` is only for internal language use and is subject to change
  --> $DIR/feature-gate-format_args_nl.rs:12:5
   |
LL |     format_args_nl!(""); //~ ERROR `format_args_nl` is only for internal language use
   |     ^^^^^^^^^^^^^^^^^^^^
   |
   = help: add #![feature(format_args_nl)] to the crate attributes to enable

error: aborting due to previous error

For more information about this error, try `rustc --explain E0658`.