error[E0277]: `Foo` cannot be sent between threads safely --> $DIR/no_send-struct.rs:15:5 | LL | bar(x); | ^^^ `Foo` cannot be sent between threads safely | = help: the trait `std::marker::Send` is not implemented for `Foo` note: required by `bar` --> $DIR/no_send-struct.rs:11:1 | LL | fn bar(_: T) {} | ^^^^^^^^^^^^^^^^^^^^^ error: aborting due to previous error For more information about this error, try `rustc --explain E0277`.