`rustc -v` should print out linker output

[jsgf]

If I compile something with rustc -v, it doesn't show the linker invocations or anything else:

$ echo "fn main() {}" > t.rs
$ rustc -v --crate-type bin t.rs
$ ls -l t
-rwxr-xr-x. 1 jsgf users 2052670 Dec  6 17:15 t

[alexcrichton]

Currently we don't actually print anything on -v other than rustc -h -v has an extended help message. Seems reasonable to me though that we'd extend the output quite a bit (e.g. with linker invocations)

[jsgf]

It used to show the linker command lines. Was dropping that a deliberate decision?

[alexcrichton]

Oh dear I had no idea that it ever used to emit the linker command line, if that stopped working it's definitely a regression!

[retep998]

I'd really appreciate if we printed the output from the linker when using -v as sometimes linkers will print out exceptionally helpful warnings.

[Nemikolh]

I found a way to get the linker output today if you need it now. You can set the RUST_LOG environnement variable to rustc_trans=info. With the nightly rust version I am using, you should see a line that says linker output.

[shepmaster]

Copying @japaric's useful tip for those of us that need the info before the request is implemented:

FWIW, you can use rustc -Z print-link-args foo.rs to see the linker invocation.

[retep998]

-Z print-link-args only prints the arguments to the linker, not the output from the linker.

[sevki]

also...

error: the option `Z` is only accepted on the nightly compiler