...with an interesting twist. I actually didn't think the following would compile:

pub mod path {
        pub use self::posix::Path_;
        pub mod posix {
                pub struct Path_;
                impl Path_ { // (1)
                        pub fn one(&self) { println!("one"); }
                }
        }
}

pub mod io {
        pub mod fs {
                use path;
                use path::Path_;
                impl path::Path_ { // (2)
                        pub fn two(&self) { println!("two"); }
                }
        }
}

fn main() {
        use path::Path_;
        Path_.one();
        Path_.two();
}

But it magically does! The twist here is that (2) used impl path::Path_ instead of impl Path_ (which would trigger a mysterious error message "found module name used as a type: impl io::fs::Path_::Path_", which is another story). Path::stat lives in (2) but rustdoc did merge its docs into (1)'s docs (with two sections). The link to (2)'s docs including Path::stat does not point the merged page, unfortunately.

This issue has worth a couple (or possibly three) of subtasks, but I wanted this issue to be described at least. Feel free to make related issues and reduce the scope of this issue.