error[E0428]: the name `test_async_fn_async` is defined multiple times
  --> tests/ui/test_fail/03-async-gt2.rs:16:1
   |
16 | async fn test_async_fn() {
   | ^^^^^^^^^^^^^^^^^^^^^^^^
   | |
   | `test_async_fn_async` redefined here
   | previous definition of the value `test_async_fn_async` here
   |
   = note: `test_async_fn_async` must be defined only once in the value namespace of this module