error[E0308]: mismatched types
  --> $DIR/mismatched-types-numeric-from.rs:2:18
   |
LL |     let _: u32 = i32::from(0_u8);
   |                  ^^^^^^^^^^^^^^^ expected u32, found i32

error: aborting due to previous error

For more information about this error, try `rustc --explain E0308`.