warning: any use of this value will cause an error
  --> $DIR/validate_uninhabited_zsts.rs:5:14
   |
LL |     unsafe { std::mem::transmute(()) }
   |              ^^^^^^^^^^^^^^^^^^^^^^^
   |              |
   |              transmuting to uninhabited type
   |              inside `foo` at $DIR/validate_uninhabited_zsts.rs:5:14
   |              inside `FOO` at $DIR/validate_uninhabited_zsts.rs:15:26
...
LL | const FOO: [Empty; 3] = [foo(); 3];
   | -----------------------------------
   |
note: the lint level is defined here
  --> $DIR/validate_uninhabited_zsts.rs:14:8
   |
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]: it is undefined behavior to use this value
  --> $DIR/validate_uninhabited_zsts.rs:18:1
   |
LL | const BAR: [Empty; 3] = [unsafe { std::mem::transmute(()) }; 3];
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered a value of uninhabited type Empty at [0]
   |
   = note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rustc repository if you believe it should not be considered undefined behavior.

warning: the type `!` does not permit zero-initialization
  --> $DIR/validate_uninhabited_zsts.rs:5:14
   |
LL |     unsafe { std::mem::transmute(()) }
   |              ^^^^^^^^^^^^^^^^^^^^^^^
   |              |
   |              this code causes undefined behavior when executed
   |              help: use `MaybeUninit<T>` instead, and only call `assume_init` after initialization is done
   |
   = note: `#[warn(invalid_value)]` on by default
   = note: the `!` type has no valid value

warning: the type `Empty` does not permit zero-initialization
  --> $DIR/validate_uninhabited_zsts.rs:18:35
   |
LL | const BAR: [Empty; 3] = [unsafe { std::mem::transmute(()) }; 3];
   |                                   ^^^^^^^^^^^^^^^^^^^^^^^
   |                                   |
   |                                   this code causes undefined behavior when executed
   |                                   help: use `MaybeUninit<T>` instead, and only call `assume_init` after initialization is done
   |
   = note: enums with no variants have no valid value

error: aborting due to previous error; 3 warnings emitted

For more information about this error, try `rustc --explain E0080`.
