llvm 6: init

[dtzWill]

Motivation for this change

Start building and testing LLVM 6, currently on RC1.

Helps ensure release doesn't have bugs re:NixOS / our projects, and hopefully enables us to at least make LLVM 6 available after final release and update the default shortly after.

Anyway, test test please! :)

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option build-use-sandbox in nix.conf on non-NixOS)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nox --run "nox-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Fits CONTRIBUTING.md.

---

[grahamc]

I introduced a failure in the evaluator today, sorry about that. Testing for a fix:

@GrahamcOfBorg eval

[dtzWill]

@GrahamcOfBorg build clang_6 lld_6 lldb_6

[GrahamcOfBorg]

Failure on aarch64-linux (full log)

Partial log (click to expand)

Apply anyway? [n]
Skipping patch.
2 out of 2 hunks ignored -- saving rejects to file lib/Support/Unix/Memory.inc.rej
builder for '/nix/store/i92fqldk238rl07g26bkjqxvkv94fra8-llvm-6.0.0rc1.drv' failed with exit code 1
cannot build derivation '/nix/store/b5jrr1h8b46ygimw9lp4drcnxn87hw8h-clang-6.0.0rc1.drv': 1 dependencies couldn't be built
cannot build derivation '/nix/store/irx1p6ad17rd4lnjzipyxk3m1d8209fm-clang-manpages-6.0.0rc1.drv': 1 dependencies couldn't be built
cannot build derivation '/nix/store/y1a9xzcngy03br51sbprglql0i5nb8ly-lld-6.0.0rc1.drv': 1 dependencies couldn't be built
cannot build derivation '/nix/store/6gz68lw4cxn3hdn07rx5k7darl2xw61p-clang-wrapper-6.0.0rc1.drv': 2 dependencies couldn't be built
cannot build derivation '/nix/store/8r11d5hv3rqxv17038nj2fwkhw9n8wqx-lldb-6.0.0rc1.drv': 2 dependencies couldn't be built
error: build of '/nix/store/6gz68lw4cxn3hdn07rx5k7darl2xw61p-clang-wrapper-6.0.0rc1.drv', '/nix/store/8r11d5hv3rqxv17038nj2fwkhw9n8wqx-lldb-6.0.0rc1.drv', '/nix/store/y1a9xzcngy03br51sbprglql0i5nb8ly-lld-6.0.0rc1.drv' failed

[GrahamcOfBorg]

Failure on x86_64-darwin (full log)

Partial log (click to expand)

[ 19%] Building CXX object lib/Analysis/CMakeFiles/LLVMAnalysis.dir/InstructionSimplify.cpp.o
[ 19%] Building CXX object lib/Analysis/CMakeFiles/LLVMAnalysis.dir/Interval.cpp.o
[ 19%] Building CXX object lib/Analysis/CMakeFiles/LLVMAnalysis.dir/IntervalPartition.cpp.o
building of '/nix/store/6sxf163jcv8cam64iv64dj0pc5jhz0g3-llvm-6.0.0rc1.drv' timed out after 1800 seconds
cannot build derivation '/nix/store/pkkf8vz9gxjbd064w8jz3z5mhc5zx2y0-clang-6.0.0rc1.drv': 1 dependencies couldn't be built
cannot build derivation '/nix/store/66swviph1yyx87n8kp0wg43d2s105lyj-clang-manpages-6.0.0rc1.drv': 1 dependencies couldn't be built
cannot build derivation '/nix/store/x3i2pb5vn93bc3alvj5rg6vhavpi5l8g-lld-6.0.0rc1.drv': 1 dependencies couldn't be built
cannot build derivation '/nix/store/1dfaybl6hm8p12mqbids4lz6aqbivg42-clang-wrapper-6.0.0rc1.drv': 2 dependencies couldn't be built
cannot build derivation '/nix/store/nkx8mn730kg13wx16vqf7wfp13javjwg-lldb-6.0.0rc1.drv': 2 dependencies couldn't be built
error: build of '/nix/store/1dfaybl6hm8p12mqbids4lz6aqbivg42-clang-wrapper-6.0.0rc1.drv', '/nix/store/nkx8mn730kg13wx16vqf7wfp13javjwg-lldb-6.0.0rc1.drv', '/nix/store/x3i2pb5vn93bc3alvj5rg6vhavpi5l8g-lld-6.0.0rc1.drv' failed

[GrahamcOfBorg]

Failure on x86_64-linux (full log)

Partial log (click to expand)

[ 40%] Building CXX object lib/Target/AMDGPU/CMakeFiles/LLVMAMDGPUCodeGen.dir/AMDGPULibCalls.cpp.o
[ 40%] Building CXX object lib/Target/AMDGPU/CMakeFiles/LLVMAMDGPUCodeGen.dir/AMDGPULibFunc.cpp.o
[ 40%] Building CXX object lib/Target/AMDGPU/CMakeFiles/LLVMAMDGPUCodeGen.dir/AMDGPULowerIntrinsics.cpp.o
building of ‘/nix/store/03ikphp5a22crk0m6vmy231ydwy8qpq1-llvm-6.0.0rc1.drv’ timed out after 3600 seconds
cannot build derivation ‘/nix/store/4w3r4s8s4yy93sd3745yy68xzx0n3h83-clang-6.0.0rc1.drv’: 1 dependencies couldn't be built
cannot build derivation ‘/nix/store/77h0vadd54g207r22m5rjzqaapvsgbg4-clang-manpages-6.0.0rc1.drv’: 1 dependencies couldn't be built
cannot build derivation ‘/nix/store/aaarl8abw7dz2lpj193wamv6s9hz16kg-lld-6.0.0rc1.drv’: 1 dependencies couldn't be built
cannot build derivation ‘/nix/store/4cigd5f184c80nr3sdq7fyzfh383xk7v-clang-wrapper-6.0.0rc1.drv’: 2 dependencies couldn't be built
cannot build derivation ‘/nix/store/3w8gb4v5bia2wlg4c037cimk1lmssiyk-lldb-6.0.0rc1.drv’: 2 dependencies couldn't be built
error: build of ‘/nix/store/3w8gb4v5bia2wlg4c037cimk1lmssiyk-lldb-6.0.0rc1.drv’, ‘/nix/store/4cigd5f184c80nr3sdq7fyzfh383xk7v-clang-wrapper-6.0.0rc1.drv’, ‘/nix/store/aaarl8abw7dz2lpj193wamv6s9hz16kg-lld-6.0.0rc1.drv’ failed

[LnL7]

Everything builds on darwin.

[LnL7]

Does this need something similar to #33871 to get python out of the closure?

[dtzWill]

Good call. Added.

[LnL7]

Should we keep exposing all of these top-level?

[LnL7]

I cleaned this up on a test branch recently, let me see if I can find it.

[dtzWill]

These all need to be refactored, was thinking of starting with refactoring 5 and 6 (possibly 4 and earlier) since they especially are so similar.

Soon (tm)!

EDIT: err, but that's not to say cleanup would be very welcome in the meantime! 👍

[dtzWill]

rc2 has been tagged, but appears they don't upload the source tarballs until the "release testers" all build and upload binaries, so should be available in a few days. Not worth bothering with grabbing off of SVN in the meantime, IMO.

[dtzWill]

rc2 has been out for a bit, but I haven't gotten to updating this yet, sorry!

[LnL7]

I don't think this is urgent since the build works.

[dtzWill]

rebased and fixed merge conflicts. Added testing variants like we have for other versions.

Will be adding musl compat fixes too, now that they're in master as well 👍.

[dtzWill]

Postponing musl fixes here while resolving discussion about musl ...

EDIT: nevermind, useful enough for my own purposes to justify :D.

[dtzWill]

rebased, rc2 -> rc3 \o/

[dtzWill]

Hold on to your lugnuts! LLVM 6 final has been tagged:

http://lists.llvm.org/pipermail/release-testers/2018-March/000667.html

Will be a few more days for them to prepare the release and official source tarballs but .... soon!!

[LnL7]

Great!

[dtzWill]

Release notes: http://releases.llvm.org/6.0.0/docs/ReleaseNotes.html

Note this adds support for "retpolines", which may be of interest to those using clang-based stdenv's.

[data-man]

Sorry, but how do I use the clang 6?
I just started using the NixOS.

[dtzWill]

I don't think it's hit any channels yet, so in the meantime you can use something like this:

$ NIX_PATH=nixpkgs=https://github.com/NixOS/nixpkgs/archive/master.tar.gz nix-shell -p clang_6

and use clang within that shell. Note that "installing" clang generally doesn't work as you may expect, there's an issue discussing this.