I am wondering why &Void is not considered an empty type, when Void is, as, IIRC, p: &Void must point to a valid value of type Void, which there cannot be.

Making this would simplify code where you pattern match on a reference of an enum of which some branches are void.

EDIT: Apparently the question was not clear enough. An empty type in Rust has nothing to do with the void type in C. I am not speaking about ZST (zero-sized types), such as (). I am speaking of types such as Infallible and !, which are defined as follows

enum Infallible {}

Being an empty type is something that propagates in Rust, for instance, consider the following

enum Void {}

struct Empty {
    foo: String,
    bar: Vec<u32>,
    boz: Void,
}

fn absurd<T>(e: Empty) -> T {
    match e {}
}

this compiles because Rust is smart enough that no value of type Empty can be created, because that would entail that there would be a value of type Void, which there isn't.

The point of the question is: why this doesn't propagate to references too.

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