warning: any use of this value will cause an error
  --> $DIR/const-err.rs:11:17
   |
LL | const FOO: u8 = [5u8][1];
   | ----------------^^^^^^^^-
   |                 |
   |                 index out of bounds: the length is 1 but the index is 1
   |
note: the lint level is defined here
  --> $DIR/const-err.rs:5:9
   |
LL | #![warn(const_err)]
   |         ^^^^^^^^^
   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
   = note: for more information, see issue #71800 <https://github.com/rust-lang/rust/issues/71800>

error[E0080]: erroneous constant used
  --> $DIR/const-err.rs:16:16
   |
LL |     black_box((FOO, FOO));
   |                ^^^ referenced constant has errors

error[E0080]: erroneous constant used
  --> $DIR/const-err.rs:16:21
   |
LL |     black_box((FOO, FOO));
   |                     ^^^ referenced constant has errors

error: aborting due to 2 previous errors; 1 warning emitted

For more information about this error, try `rustc --explain E0080`.
Future incompatibility report: Future breakage diagnostic:
warning: any use of this value will cause an error
  --> $DIR/const-err.rs:11:17
   |
LL | const FOO: u8 = [5u8][1];
   | ----------------^^^^^^^^-
   |                 |
   |                 index out of bounds: the length is 1 but the index is 1
   |
note: the lint level is defined here
  --> $DIR/const-err.rs:5:9
   |
LL | #![warn(const_err)]
   |         ^^^^^^^^^
   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
   = note: for more information, see issue #71800 <https://github.com/rust-lang/rust/issues/71800>