error[E0277]: `*mut u8` cannot be sent between threads safely --> $DIR/kindck-send-owned.rs:12:19 | LL | assert_send::>(); | ^^^^^^^^^^^^ `*mut u8` cannot be sent between threads safely | = help: the trait `Send` is not implemented for `*mut u8`, which is required by `Box<*mut u8>: Send` = note: required for `Unique<*mut u8>` to implement `Send` note: required because it appears within the type `Box<*mut u8>` --> $SRC_DIR/alloc/src/boxed.rs:LL:COL note: required by a bound in `assert_send` --> $DIR/kindck-send-owned.rs:3:18 | LL | fn assert_send() { } | ^^^^ required by this bound in `assert_send` error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0277`.