error[E0603]: static `TO_STDERR` is private
  --> $DIR/derive_with_visibility.rs:27:24
   |
27 |     if inner_for_test::TO_STDERR.is_present() {
   |                        ^^^^^^^^^ this static is private
   |
note: the static `TO_STDERR` is defined here
  --> $DIR/derive_with_visibility.rs:14:14
   |
14 |     #[derive(GFlags)]
   |              ^^^^^^
   = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)