adding openbsd snapshot

[dhuseby]

@alexcrichton please upload this snapshot when landing:

https://github.com/dhuseby/rust-manual-snapshots/raw/master/rust-stage0-2015-08-11-1af31d4-openbsd-x86_64-9cae790c4ca19b1b29a048605ce249fe1c20a498.tar.bz2

BTW, this is the snapshot that @semarie has published on his website for use in the OpenBSD port for rust. Credit goes to him.

[rust-highfive]

r? @brson

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[alexcrichton]

@bors: r+ 2425b9d

Thanks @dhuseby and @semarie!

[dhuseby]

@semarie I have started setting up an OpenBSD buildbot. You can see it's status here:
http://buildbot.rust-lang.org/buildslaves/openbsd-64-opt
I was looking at your port and it appears that the configure scripts need some plumbing work done around egcc vs gcc so that it detects gcc 4.9 instead of the default gcc 4.2. If you've got suggestions/patches, that would be awesome. Otherwise, I can figure it out.

My ultimate plan is to have the buildbot building snapshots for both rust and cargo since I can successfully bootstrap cargo on pretty much any platform rust compiles on.

[semarie]

@dhuseby thanks for you work !

For building rust from git under openbsd, you could see the README at http://semarie.free.fr/rust/. (The openbsd ports have implicit PATH that change one thing or two for using gcc-4.9).

The current "limitation" is really the need to use gcc from ports (4.9). All the teaks are for that (even the jemalloc force_tls="0" that is detected differently with base gcc or ports gcc, if I recall well).

gcc-4.9 is need: at configure, at build, at target linking.

I don't known what would be the better method: it could be configured in the buildbot with specific environment variable I think.

I have also a local patch for generating openbsd snapshot, in order to include system-libraries needed for stage0. I will see to make a PR for it.

[semarie]

oh and I omit a file edition for linking with libestdc++ instead of libstdc++ (src/etc/mklldeps.py) . This one fill be more complex to deal with it, I think.

[bors]

⌛ Testing commit 2425b9d with merge a8b1bf7...

[bors]

💔 Test failed - auto-linux-32-nopt-t

[alexcrichton]

@bors: retry

[bors]

⌛ Testing commit 2425b9d with merge 8115b39...

[bors]

☀️ Test successful - auto-linux-32-nopt-t, auto-linux-32-opt, auto-linux-64-nopt-t, auto-linux-64-opt, auto-linux-64-x-android-t, auto-mac-32-opt, auto-mac-64-nopt-t, auto-mac-64-opt, auto-win-gnu-32-nopt-t, auto-win-gnu-32-opt, auto-win-gnu-64-nopt-t, auto-win-gnu-64-opt, auto-win-msvc-32-opt, auto-win-msvc-64-opt