Compiling playground v0.0.1 (/playground)
error[E0308]: mismatched types
 --> src/lib.rs:2:5
  |
1 | pub fn f<T>(a: &T) -> *const T {
  |          -            -------- expected `*const T` because of return type
  |          |
  |          this type parameter
2 |     &1 as *const i32
  |     ^^^^^^^^^^^^^^^^ expected type parameter `T`, found `i32`
  |
  = note: expected raw pointer `*const T`
             found raw pointer `*const i32`

error: aborting due to previous error

For more information about this error, try `rustc --explain E0308`.
error: could not compile `playground`

To learn more, run the command again with --verbose.