error[E0658]: yield syntax is experimental
  --> $DIR/feature-gate-generators.rs:2:5
   |
LL |     yield true;
   |     ^^^^^^^^^^
   |
   = note: for more information, see https://github.com/rust-lang/rust/issues/43122
   = help: add #![feature(generators)] to the crate attributes to enable

error[E0627]: yield statement outside of generator literal
  --> $DIR/feature-gate-generators.rs:2:5
   |
LL |     yield true;
   |     ^^^^^^^^^^

error: aborting due to 2 previous errors

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