warning: any use of this value will cause an error
  --> $DIR/pub_const_err.rs:6:20
   |
LL | pub const Z: u32 = 0 - 1;
   | ----------------   ^^^^^ attempt to compute `0_u32 - 1_u32`, which would overflow
   |
note: the lint level is defined here
  --> $DIR/pub_const_err.rs:2:9
   |
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>

warning: 1 warning emitted

Future incompatibility report: Future breakage diagnostic:
warning: any use of this value will cause an error
  --> $DIR/pub_const_err.rs:6:20
   |
LL | pub const Z: u32 = 0 - 1;
   | ----------------   ^^^^^ attempt to compute `0_u32 - 1_u32`, which would overflow
   |
note: the lint level is defined here
  --> $DIR/pub_const_err.rs:2:9
   |
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>