error[E0390]: only a single inherent implementation marked with `#[lang = "mut_ptr"]` is allowed for the `*mut T` primitive --> $DIR/E0390.rs:15:1 | LL | impl *mut Foo {} //~ ERROR E0390 | ^^^^^^^^^^^^^^^^ | help: consider using a trait to implement these methods --> $DIR/E0390.rs:15:1 | LL | impl *mut Foo {} //~ ERROR E0390 | ^^^^^^^^^^^^^^^^ error: aborting due to previous error For more information about this error, try `rustc --explain E0390`.