tbb: adds better CMake support #70606
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This adds a FindTBB.cmake file that should help using TBB in projects that already use CMake to find dependencies
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At a first impression, I'm afraid I don't think this is something that we should add to nixpkgs itself. This seems like a file that is better suited to go into TBB upstream itself, so that all packages across distros can benefit from it widely, and the maintainers can correctly care for it. We generally try to have Nix built packages maintain "parity" across distros -- adding things like this means there's something we have that others don't, and this invariably will cause some conflicts or user issues later on (for example if some project includes a copy of this file, and we include this one in the default setupHook, which would CMake load?) "Principle of least surprise" somewhat applies here.
Futhermore, most people packaging CMake projects have an array of extra FindXXX.cmake modules they vendor themselves to handle these things, for various reasons. If upstream doesn't want to accept this kind of maintenance burden, I think the traditional route is for them to copy this file themselves and maintain it. (This file has a copyright date for 2015, so it clearly is from somewhere, like another project?) If that's what the current situation is, and for some reason this FindTBB code cannot find the Nix tbb package in a Nix build environment, we should fix that, not simply include this file into our package.
If this CMake file is widely distributed and in use by tons of other distros (and shipped by them for their packages!) then I'd reconsider this.
| postFixup = '' | ||
| substituteAll ${./FindTBB.cmake} $out/FindTBB.cmake | ||
| ''; | ||
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How is this supposed to work? If my memory serves correctly, our CMake setup hooks do not search $out but actually search some path like $out/share/cmake for all buildInputs in order to find .cmake files. You'd have to have some other workaround for this anyway, wouldn't you?
This adds a FindTBB.cmake file that should help using TBB
in projects that already use CMake to find dependencies
Motivation for this change
TBB is usually not findable by CMake, this makes it so that CMake based packages can more easily find tbb
Things done
sandboxinnix.confon non-NixOS)nix-shell -p nix-review --run "nix-review wip"./result/bin/)nix path-info -Sbefore and after)Notify maintainers
cc @thoughtpolice @DIzFer