Cross-compilation of Haskell packages with custom setup program

[bgamari]

Issue description

Currently cross-compilation is broken as Setup.hs is built against host packages, rather than build packages (buildHaskellPackages) as it should be.

Steps to reproduce

$ git clone git@github.com:nixos/nixpkgs
$ git -C nixpkgs checkout 51a345c6bb5010fda083ed7e1467b1b5e267fe4e
$ cat <<EOF >default.nix
let
  config_module = {config, lib, pkgs, ... }: {
    environment.systemPackages = with pkgs; [
      perlXMLParser
      haskellPackages.heaps
    ];
    nixpkgs.crossSystem = {
      config = "armv7l-unknown-linux-gnueabihf";
      arch = "armv7l";
      float = "hard";
      fpu = "vfpv3-d16";
      withTLS = true;
      openssl.system = "linux-armv4";
      platform = pkgs.platforms.armv7l-hf-multiplatform // {
        kernelBaseConfig = "xilinx_zynq_defconfig";
        kernelTarget = "uImage";
        kernelMakeFlags = [ "LOADADDR=0x0200000" ];
        uboot = pkgs.ubootMicrozed;
      };
    };

    boot.loader.grub.enable = false;
    boot.loader.generic-extlinux-compatible.enable = true;
    boot.kernelPackages = pkgs.linuxPackagesFor pkgs.linux;
    boot.kernelParams = [];
    boot.supportedFilesystems = [ "vfat" ];
  };

  nixos = import ./nixpkgs/nixos {
    configuration = {
      imports = [ config_module ];

      environment.noXlibs = true;
      documentation.info.enable = false;
      fonts.fontconfig.enable = false;
      security.polkit.enable = false;
      security.rngd.enable = false;
      system.autoUpgrade.enable = false;
      services.udisks2.enable = false;
      services.nixosManual.enable = false;
      services.bind.enable = false;

      #nixpkgs.overlays = [ (import ./overlay) ];
      nixpkgs.config.allowBroken = true;

      fileSystems."/".device = "/dev/mmcblk0p2";

      # FIXME: this probably should be in installation-device.nix
      users.extraUsers.root.initialHashedPassword = "";
    };
  };

in
  nixos
EOF
$ nix build -f . pkgs.haskellPackages.heaps
...
  compileBuildDriverPhase
  setupCompileFlags: -package-db=/tmp/nix-build-heaps-0.3.6-armv7l-unknown-linux-gnueabihf.drv-0/package.conf.d -j16 -threaded
  [1 of 1] Compiling Main             ( Setup.lhs, /tmp/nix-build-heaps-0.3.6-armv7l-unknown-linux-gnueabihf.drv-0/Main.o )

  Setup.lhs:12:1: error:
      Bad interface file: /nix/store/k2cmlas0kjj1zbh7yzy4lv3y5v544zf1-cabal-doctest-1.0.6-armv7l-unknown-linux-gnueabihf/lib/ghc-8.2.2/cabal-doctest-1.0.6/Distribution/Extra/Doctest.hi
          magic number mismatch: old/corrupt interface file? (wanted 33214052, got 129742)
     |
  12 | import Distribution.Extra.Doctest ( defaultMainWithDoctests )
     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Technical details

Please run nix-shell -p nix-info --run "nix-info -m" and paste the
results.

[bgamari]

It's possible that @angerman fixes this in #37254.

[Ericson2314]

Isn't this fixed now?

[stale]

Thank you for your contributions.

This has been automatically marked as stale because it has had no activity for 180 days.

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