error[E0724]: `#[ffi_returns_twice]` may only be used on foreign functions
  --> $DIR/ffi_returns_twice.rs:4:1
   |
LL | #[ffi_returns_twice]
   | ^^^^^^^^^^^^^^^^^^^^

error[E0724]: `#[ffi_returns_twice]` may only be used on foreign functions
  --> $DIR/ffi_returns_twice.rs:7:1
   |
LL | #[ffi_returns_twice]
   | ^^^^^^^^^^^^^^^^^^^^

error[E0724]: `#[ffi_returns_twice]` may only be used on foreign functions
  --> $DIR/ffi_returns_twice.rs:13:5
   |
LL |     #[ffi_returns_twice]
   |     ^^^^^^^^^^^^^^^^^^^^

error: aborting due to 3 previous errors

For more information about this error, try `rustc --explain E0724`.