error[E0119]: conflicting implementations of trait `std::convert::From>` for type `MyError<_>`: --> $DIR/so-37347311.rs:21:1 | LL | impl From for MyError { //~ ERROR conflicting implementations | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | = note: conflicting implementation in crate `core`: - impl std::convert::From for T; error: aborting due to previous error For more information about this error, try `rustc --explain E0119`.