rustc: emitting only metadata causes no output

[Ruin0x11]

I'm trying to obtain the rustc analysis metadata for a single .rs file, but not specifying a binary object type inside emit causes no output.

test.rs:

//! # Documentation Example
//! An example for figuring out metadata emission.

/// Begins the program.
fn main() {
    println!("Hello, world!");
}

Commands:

 » ls -a
.	..	test.rs
 » rustc --emit=metadata test.rs
 » ls -a
.	..	test.rs
 » rustc --emit=metadata,link test.rs
 » ls -a
.		..		libtest.rmeta	test		test.rs

[alexcrichton]

cc @nrc

[theishshah]

I can hop on this!

[nrc]

Thanks @theishshah - let me know if you need any help - I'm also 'nrc' on irco