error[E0277]: `*mut &'a isize` cannot be sent between threads safely --> $DIR/kindck-send-unsafe.rs:6:19 | LL | assert_send::<*mut &'a isize>(); | ^^^^^^^^^^^^^^ `*mut &'a isize` cannot be sent between threads safely | = help: the trait `Send` is not implemented for `*mut &'a isize` note: required by a bound in `assert_send` --> $DIR/kindck-send-unsafe.rs:3:18 | LL | fn assert_send() { } | ^^^^ required by this bound in `assert_send` error: aborting due to previous error For more information about this error, try `rustc --explain E0277`.