Update openbsd targets

[semarie]

• add a new target aarch64-unknown-openbsd
• update i686-unknown-openbsd to use lld with clang, in order to correctly link binaries with i128

[rust-highfive]

r? @pnkfelix

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[semarie]

r? @alexcrichton

[rust-highfive]

The job x86_64-gnu-llvm-3.9 of your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

[00:05:25]    Compiling ena v0.9.2
[00:05:25]    Compiling jobserver v0.1.11
[00:05:27]    Compiling parking_lot_core v0.2.14
[00:05:27]    Compiling tempdir v0.3.7
[00:05:29] error[E0432]: unresolved import `LinkerFlavor`
[00:05:29]   --> librustc_target/spec/aarch64_unknown_openbsd.rs:11:5
[00:05:29] 11 | use LinkerFlavor;
[00:05:29] 11 | use LinkerFlavor;
[00:05:29]    |     ^^^^^^^^^^^^ no `LinkerFlavor` in the root
[00:05:29] 
[00:05:29] error[E0432]: unresolved import `target`
[00:05:29]   --> librustc_target/spec/aarch64_unknown_openbsd.rs:12:5
[00:05:29]    |
[00:05:29] 12 | use target::{Target, TargetResult};
[00:05:29]    |     ^^^^^^ Maybe a missing `extern crate target;`?
[00:05:29]    Compiling rustc_apfloat v0.0.0 (file:///checkout/src/librustc_apfloat)
[00:05:30]    Compiling rls-span v0.4.0
[00:05:31] error: aborting due to 2 previous errors
[00:05:31] 
[00:05:31] 
[00:05:31] For more information about this error, try `rustc --explain E0432`.
[00:05:31] error: Could not compile `rustc_target`.
[00:05:31] 
[00:05:31] Caused by:
[00:05:31]   process didn't exit successfully: `/checkout/obj/build/bootstrap/debug/rustc --crate-name rustc_target librustc_target/lib.rs --color always --error-format json --crate-type dylib --emit=dep-info,link -C prefer-dynamic -C opt-level=3 --cfg feature="jemalloc" -C metadata=aed9d8ab86b35123 -C extra-filename=-aed9d8ab86b35123 --out-dir /checkout/obj/build/x86_64-unknown-linux-gnu/stage0-rustc/x86_64-unknown-linux-gnu/release/deps --target x86_64-unknown-linux-gnu -L dependency=/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-rustc/x86_64-unknown-linux-gnu/release/deps -L dependency=/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-rustc/release/deps --extern serialize=/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-rustc/x86_64-unknown-linux-gnu/release/deps/libserialize-946eff7380f27f57.so --extern serialize=/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-rustc/x86_64-unknown-linux-gnu/release/deps/libserialize-946eff7380f27f57.rlib --extern bitflags=/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-rustc/x86_64-unknown-linux-gnu/release/deps/libbitflags-401bddd0d1809e53.rlib --extern rustc_cratesio_shim=/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-rustc/x86_64-unknown-linux-gnu/release/deps/librustc_cratesio_shim-a7895f6d3b02c33b.so --extern log=/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-rustc/x86_64-unknown-linux-gnu/release/deps/liblog-4f0866e958f59455.rlib` (exit code: 101)
Sat, 12 May 2018 08:06:31 GMT
travis_time:end:07ffbbee:start=1526112391244265537,finish=1526112391306706563,duration=62441026

The command "date && (curl -fs --head https://google.com | grep ^Date: | sed 's/Date: //g' || true)

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

[sanxiyn]

@bors r+

[bors]

📌 Commit f430d7c has been approved by sanxiyn