error: casting character literal to u8. `char`s are 4 bytes wide in rust, so casting to u8 truncates them --> char_lit_as_u8.rs:7:13 | 7 | let c = 'a' as u8; | ^^^^^^^^^ | = note: `-D char-lit-as-u8` implied by `-D warnings` = help: Consider using a byte literal instead: b'a' error: aborting due to previous error To learn more, run the command again with --verbose.