error[E0277]: the trait bound `&[i8]: From<&[u8]>` is not satisfied --> $DIR/issue-71394-no-from-impl.rs:8:25 | LL | let _: &[i8] = data.into(); | ^^^^ the trait `From<&[u8]>` is not implemented for `&[i8]` | = help: the following other types implement trait `From`: <[bool; LANES] as From>> <[T; N] as From>> <[T; 1] as From<(T,)>> <[T; 2] as From<(T, T)>> <[T; 3] as From<(T, T, T)>> <[T; 4] as From<(T, T, T, T)>> <[T; 5] as From<(T, T, T, T, T)>> <[T; 6] as From<(T, T, T, T, T, T)>> and 6 others = note: required for `&[u8]` to implement `Into<&[i8]>` error: aborting due to previous error For more information about this error, try `rustc --explain E0277`.