| //@ run-pass |
| |
| // rpass test for reservation impls. Not 100% required because `From` uses them, |
| // but still. |
| |
| //@ revisions: old next |
| //@[next] compile-flags: -Znext-solver |
| |
| #![feature(rustc_attrs)] |
| |
| use std::mem; |
| |
| trait MyTrait<S> { |
| fn foo(&self, s: S) -> usize; |
| } |
| |
| #[rustc_reservation_impl = "foo"] |
| impl<T> MyTrait<u64> for T { |
| fn foo(&self, _x: u64) -> usize { 0 } |
| } |
| |
| // reservation impls don't create coherence conflicts, even with |
| // non-chain overlap. |
| impl<S> MyTrait<S> for u32 { |
| fn foo(&self, _x: S) -> usize { mem::size_of::<S>() } |
| } |
| |
| fn main() { |
| // ...and the non-reservation impl gets picked.XS |
| assert_eq!(0u32.foo(0u64), mem::size_of::<u64>()); |
| } |
