Fix build failure on FreeBSD, due to useless annotations.

[dcci]

This patch tries to fix a failure I hit while trying to build rust on FreeBSD.

Example:

src/libcore/result.rs:253:54: 253:56 error: This stability annotation is useless
src/libcore/result.rs:253     Ok(#[stable(feature = "rust1", since = "1.0.0")] T),
                                                                               ^~
src/libcore/result.rs:257:55: 257:57 error: This stability annotation is useless
src/libcore/result.rs:257     Err(#[stable(feature = "rust1", since = "1.0.0")] E)
                                                                                ^~

I'm not terribly sure this is correct as this is my first contribution to rust, but still i thougth it was worth a try. Also, isn't the annotation highlighting the wrong piece? (T and E instead of #[stable ...]).

Thanks!

Davide

[sfackler]

Those annotations are supposed to be there. You may be building with an out of date snapshot?

[dcci]

Hmm, not really, c9629d6

[sfackler]

It looks like the most recent snapshot hasn't been built for freebsd, which would cause this error: https://github.com/rust-lang/rust/blob/master/src/snapshots.txt#L1

[dcci]

Thanks! I'm not terribly familiar with that -- is there something that can be done to get this moving forward?

[alexcrichton]

Ah yeah these are currently required and we just need some new FreeBSD snapshots. It should be possible to check out the snapshot revision, and then run make snap-stage3, and then we can upload the resulting tarball.

[dcci]

@alexcrichton OK, I'm going to run that. Should I upload them somewhere and then open another pull request, or something else? Thanks!

[alexcrichton]

Yeah feel free to just send me a link to the snapshot when it's done and I can upload it.

[dcci]

@alexcrichton Here it is.
http://people.freebsd.org/~davide/rust/rust-stage0-2016-02-17-4d3eebf-freebsd-x86_64-f38991fbb81c1cd8d0bbda396f98f13a55b42804.tar.bz2

[alexcrichton]

Thanks @dcci! This actually also ended up being independently produced by @andoriyu in #32197, and I've uploaded that snapshot so once the PR lands FreeBSD should be good to go!