error[E0053]: method `jumbo` has an incompatible type for trait --> $DIR/impl-method-mismatch.rs:7:5 | LL | unsafe fn jumbo(&self, x: &usize) { *self + *x; } | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected normal fn, found unsafe fn | note: type in trait --> $DIR/impl-method-mismatch.rs:2:5 | LL | fn jumbo(&self, x: &usize) -> usize; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ = note: expected signature `fn(&usize, &usize) -> usize` found signature `unsafe fn(&usize, &usize)` error: aborting due to previous error For more information about this error, try `rustc --explain E0053`.