tests/ui/traits/new-solver/runaway-impl-candidate-selection.rs

   1 // compile-flags: -Ztrait-solver=next
   2
   3 // In the new solver, we are trying to select `<?0 as Iterator>::Item: Debug`,
   4 // which, naively can be unified with every impl of `Debug` if we're not careful.
   5 // This test makes sure that we treat projections with inference var substs as
   6 // placeholders during fast reject.
   7
   8 fn iter<T: Iterator>() -> <T as Iterator>::Item {
   9     todo!()
  10 }
  11
  12 fn main() {
  13     println!("{:?}", iter::<_>());
  14     //~^ ERROR type annotations needed
  15 }