error[E0277]: the trait bound `*mut (): Trait<'_>` is not satisfied --> $DIR/issue-101623.rs:21:21 | LL | Trait::do_stuff({ fun(&mut *inner) }); | --------------- ^^----------------^^ | | | | | the trait `Trait<'_>` is not implemented for `*mut ()` | required by a bound introduced by this call | = help: the trait `Trait<'_>` is not implemented for `*mut ()` but it is implemented for `()` = help: for that trait implementation, expected `()`, found `*mut ()` error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0277`.