error: attempt to subtract with overflow --> $DIR/const-len-underflow-separate-spans.rs:17:20 | LL | const LEN: usize = ONE - TWO; | ^^^^^^^^^ | = note: #[deny(const_err)] on by default error[E0080]: constant evaluation error --> $DIR/const-len-underflow-separate-spans.rs:17:20 | LL | const LEN: usize = ONE - TWO; | ^^^^^^^^^ attempt to subtract with overflow error[E0080]: could not evaluate constant expression --> $DIR/const-len-underflow-separate-spans.rs:22:12 | LL | let a: [i8; LEN] = unimplemented!(); | ^^^^^---^ | | | referenced constant has errors error: aborting due to 3 previous errors For more information about this error, try `rustc --explain E0080`.