llvmPackages_{12,13,14}: Disable tests on RISC-V

[zhaofengli]

Description of changes

Same rationale as #125132 😢 Not required on LLVM 15 since the test suite runs fine.

Ref: #101651

Things done

• Built on platform(s)
  • riscv64-linux
• For non-Linux: Is sandbox = true set in nix.conf? (See Nix manual)
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 23.05 Release Notes (or backporting 22.11 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
  • (Release notes changes) Ran nixos/doc/manual/md-to-db.sh to update generated release notes
• Fits CONTRIBUTING.md.

[SuperSandro2000]

Same rationale as #125132 😢

Could we add a very short comment with that?

[zhaofengli]

Marking as draft until I test out LLVM 15. Now LLD finally supports RISC-V linker relaxation so we may want to switch to that by default.

[zhaofengli]

With LLVM 15, all tests passed just fine on RISC-V 🎉 I'll build test more packages and open a separate PR to change the default LLVM version.

running tests
check flags: -j4 check-all
[1/2] Preparing lit tests
[1/2] Running all regression tests
-- Testing: 43965 tests, 4 workers --

Testing Time: 7874.56s
  Skipped          :     8
  Unsupported      :  1973
  Passed           : 48212
  Expectedly Failed:   172
checkPhase completed in 2 hours 12 minutes 0 seconds

[SeTSeR]

Which board was LLVM15 tested on? I tried to build LLVM on my visionfive2, and there is still one test failing (I don’t have a full build log at hand right now, but I’m pretty sure that was PerfEventTest). So maybe disable tests for LLVM15 too?