Erasing inner attributes in blocks

[bepvte]

#![allow(unused)]
struct Biz {
    field: usize,
}

fn r() -> (Biz, ()) {
    (
        Biz{
            #![cfg(unix)]
            field: 9,
        },
        Biz{
            #![cfg(not(unix))]
            field: 200,
        },
        ()
    )
}
fn main() {
    println!("Hello, world!");
}

(Playground)

Running rustfmt on this code erases the #![cfgs], and creates an invalid return type. I am not sure if the tuple is necessary but I had one when I first encountered the bug.

This occurs no matter how many fields are in the struct or block.

This seems similar to #2073, but since that issue is so old and marked as solved I felt it would be better to open a new one.

rustfmt 1.2.2-nightly (5274b49 2019-04-24)