| /// The compiler previously did not properly check the bound of `From` when it was used from type |
| /// of the dyn trait object (use in `copy_any` below). Since the associated type is under user |
| /// control in this usage, the compiler could be tricked to believe any type implemented any trait. |
| /// This would ICE, except for pure marker traits like `Copy`. It did not require providing an |
| /// instance of the dyn trait type, only name said type. |
| trait Setup { |
| type From: Copy; |
| } |
| |
| fn copy<U: Setup + ?Sized>(from: &U::From) -> U::From { |
| *from |
| } |
| |
| pub fn copy_any<T>(t: &T) -> T { |
| copy::<dyn Setup<From=T>>(t) |
| //~^ ERROR the trait bound `T: Copy` is not satisfied |
| } |
| |
| fn main() {} |
