1error[E0277]: the size for values of type `Self` cannot be known at compilation time 2 --> $DIR/issue-20005.rs:10:49 3 | 4LL | ) -> <Dst as From<Self>>::Result where Dst: From<Self> { 5 | ^^^^^^^^^^ doesn't have a size known at compile-time 6 | 7note: required by a bound in `From` 8 --> $DIR/issue-20005.rs:1:12 9 | 10LL | trait From<Src> { 11 | ^^^ required by this bound in `From` 12help: consider further restricting `Self` 13 | 14LL | ) -> <Dst as From<Self>>::Result where Dst: From<Self>, Self: Sized { 15 | +++++++++++++ 16help: consider relaxing the implicit `Sized` restriction 17 | 18LL | trait From<Src: ?Sized> { 19 | ++++++++ 20 21error: aborting due to previous error 22 23For more information about this error, try `rustc --explain E0277`. 24