// For `Send` generators, suggest a `T: Sync` requirement for `&T` upvars, // and suggest a `T: Send` requirement for `&mut T` upvars. #![feature(generators)] fn assert_send(_: T) {} //~^ NOTE required by a bound in `assert_send` //~| NOTE required by this bound in `assert_send` //~| NOTE required by a bound in `assert_send` //~| NOTE required by this bound in `assert_send` fn main() { let x: &*mut () = &std::ptr::null_mut(); let y: &mut *mut () = &mut std::ptr::null_mut(); assert_send(move || { //~^ ERROR generator cannot be sent between threads safely //~| NOTE generator is not `Send` yield; let _x = x; }); //~^^ NOTE captured value is not `Send` because `&` references cannot be sent unless their referent is `Sync` //~| NOTE has type `&*mut ()` which is not `Send`, because `*mut ()` is not `Sync` assert_send(move || { //~^ ERROR generator cannot be sent between threads safely //~| NOTE generator is not `Send` yield; let _y = y; }); //~^^ NOTE captured value is not `Send` because `&mut` references cannot be sent unless their referent is `Send` //~| NOTE has type `&mut *mut ()` which is not `Send`, because `*mut ()` is not `Send` }