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warning: the type `!` does not permit zero-initialization
--> $DIR/validate_uninhabited_zsts.rs:4:14
|
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: the `!` type has no valid value
= note: `#[warn(invalid_value)]` on by default
error[E0080]: evaluation of constant value failed
--> $DIR/validate_uninhabited_zsts.rs:4:14
|
LL | unsafe { std::mem::transmute(()) }
| ^^^^^^^^^^^^^^^^^^^^^^^ transmuting to uninhabited type
|
note: inside `foo`
--> $DIR/validate_uninhabited_zsts.rs:4:14
|
LL | unsafe { std::mem::transmute(()) }
| ^^^^^^^^^^^^^^^^^^^^^^^
note: inside `FOO`
--> $DIR/validate_uninhabited_zsts.rs:19:33
|
LL | const FOO: [empty::Empty; 3] = [foo(); 3];
| ^^^^^
error[E0080]: it is undefined behavior to use this value
--> $DIR/validate_uninhabited_zsts.rs:21:1
|
LL | const BAR: [empty::Empty; 3] = [unsafe { std::mem::transmute(()) }; 3];
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value at [0].0: encountered a value of uninhabited type empty::Void
|
= 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.
= note: the raw bytes of the constant (size: 0, align: 1) {}
warning: the type `empty::Empty` does not permit zero-initialization
--> $DIR/validate_uninhabited_zsts.rs:21:42
|
LL | const BAR: [empty::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: in this struct field
--> $DIR/validate_uninhabited_zsts.rs:16:22
|
LL | pub struct Empty(Void);
| ^^^^
note: enums with no inhabited variants have no valid value
--> $DIR/validate_uninhabited_zsts.rs:13:5
|
LL | enum Void {}
| ^^^^^^^^^
error: aborting due to 2 previous errors; 2 warnings emitted
For more information about this error, try `rustc --explain E0080`.
|
