// run-rustfix trait Trait {} impl Trait for () {} // this works fn foo() -> impl Trait { () } fn bar<T: Trait + std::marker::Sync>() -> T where T: Send, { () //~ ERROR mismatched types } fn other_bounds<T>() -> T where T: Trait, Vec<usize>: Clone, { () //~ ERROR mismatched types } fn main() { foo(); bar::<()>(); other_bounds::<()>(); }