re2: switch to CMake

[azahi]

Description of changes

• Switch to CMake
• Add myself as a maintainer
• Refactor the derivation

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• 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/)
• 22.11 Release Notes (or backporting 22.05 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.

[azahi]

Since this causes quite a lot of rebuilds, maybe we should target the staging branch here?

[risicle]

Fails to build on macos 10.15:

fixing cmake files...
mkdir: cannot create directory 'build': File exists

[Mic92]

Fails to build on macos 10.15:

fixing cmake files...
mkdir: cannot create directory 'build': File exists

This is a weird error, if you look at pkgs/development/tools/build-managers/cmake/setup-hook.sh

  if [ -z "${dontUseCmakeBuildDir-}" ]; then         
      mkdir -p "$cmakeBuildDir"                      
      cd "$cmakeBuildDir"                            
      : ${cmakeDir:=..}                              
  else                                               
      : ${cmakeDir:=.}                               
  fi                                                 

mkdir -p should not fail even if the directory exists.

Can you do preConfigure = "set -x" to confirm this is the mkdir that fails, also does dontUseCmakeBuildDir = 1; in the build fixes it?

[tobim]

Fails to build on macos 10.15:

fixing cmake files...
mkdir: cannot create directory 'build': File exists

This is a weird error, ...

mkdir -p should not fail even if the directory exists.

mkdir -p fails because the path is a regular file called BUILD, not a directory. It only happens on darwin because of the case insensitive filesystem.

[azahi]

It only happens on darwin because of the case insensitive filesystem.

I've added cmakeBuildDir = "build_dir";. Let's see if that helps.

[tobim]

Looks alright to me !

[risicle]

passthru.tests build on macos 10.15 & nixos x86_64. pkgsMusl, pkgsStatic & pkgsCross.aarch64-multiplatform variants still build.

This needs to be re-targeted at staging though.

[azahi]

Well, I've changed the target branch and now ofborg gets this:

error: building of '/nix/store/05bx6ql14syldhylnywgn3k80spsdxgv-llvm-11.1.0.drv!lib,out' from .drv file timed out after 3600 seconds

I'm not sure how to proceed from here.

[tobim]

Well, I've changed the target branch and now ofborg gets this:

error: building of '/nix/store/05bx6ql14syldhylnywgn3k80spsdxgv-llvm-11.1.0.drv!lib,out' from .drv file timed out after 3600 seconds

I'm not sure how to proceed from here.

Probably just an unrelated problem on the stating branch, nothing to worry about.

[risicle]

Ofborg frequently fails to build on the staging branch because it can't use binaries from hydra and so has often has to build a huge number of dependencies for simple packages, which frequently timeout. It's not related to this PR specifically.

[azahi]

Is there anything I can do here? I really want to get this in before the 22.11 release.

[nixos-discourse]

This pull request has been mentioned on NixOS Discourse. There might be relevant details there:

https://discourse.nixos.org/t/struggling-with-cmake-dependencies/22629/4

[nixos-discourse]

This pull request has been mentioned on NixOS Discourse. There might be relevant details there:

https://discourse.nixos.org/t/prs-already-reviewed/2617/651