error: any use of this value will cause an error
  --> $DIR/const_panic.rs:4:19
   |
LL | pub const Z: () = panic!("cheese");
   | ------------------^^^^^^^^^^^^^^^^-
   |                   |
   |                   the evaluated program panicked at 'cheese', $DIR/const_panic.rs:4:19
   |
   = note: `#[deny(const_err)]` on by default
   = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)

error: any use of this value will cause an error
  --> $DIR/const_panic.rs:7:19
   |
LL | pub const Y: () = unreachable!();
   | ------------------^^^^^^^^^^^^^^-
   |                   |
   |                   the evaluated program panicked at 'internal error: entered unreachable code', $DIR/const_panic.rs:7:19
   |
   = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)

error: any use of this value will cause an error
  --> $DIR/const_panic.rs:10:19
   |
LL | pub const X: () = unimplemented!();
   | ------------------^^^^^^^^^^^^^^^^-
   |                   |
   |                   the evaluated program panicked at 'not yet implemented', $DIR/const_panic.rs:10:19
   |
   = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)

error: aborting due to 3 previous errors