Use build GHC and packages for building setup

Author: hamishmack

builder/default.nix

@@ -9,7 +9,7 @@ let
   setup-builder = haskellLib.weakCallPackage pkgs ./setup-builder.nix {
     ghc = buildGHC;
     hsPkgs = hsPkgs.buildPackages;
-    inherit haskellLib nonReinstallablePkgs makeConfigFiles;
+    inherit haskellLib nonReinstallablePkgs makeSetupConfigFiles;
   };
 
   # Wraps GHC to provide dependencies in a way that works for both the
@@ -25,6 +25,11 @@ let
   makeConfigFiles = haskellLib.weakCallPackage pkgs ./make-config-files.nix {
     inherit ghc haskellLib nonReinstallablePkgs;
   };
+  # When building setup depends we need to use the build systems GHC and Packages
+  makeSetupConfigFiles = haskellLib.weakCallPackage buildPackages ./make-config-files.nix {
+    inherit buildGHC haskellLib nonReinstallablePkgs;
+  };
+
 
   hoogleLocal = let
     nixpkgsHoogleLocal = import (pkgs.path + /pkgs/development/haskell-modules/hoogle.nix);

builder/setup-builder.nix

@@ -1,4 +1,4 @@
-{ stdenv, lib, buildPackages, haskellLib, ghc, nonReinstallablePkgs, hsPkgs, makeConfigFiles }:
+{ stdenv, lib, buildPackages, haskellLib, ghc, nonReinstallablePkgs, hsPkgs, makeSetupConfigFiles }:
 
 { setup-depends, package, name, src, flags }:
 
@@ -7,7 +7,7 @@ let
 
   includeGhcPackage = lib.any (p: p.identifier.name == "ghc") setup-depends;
 
-  configFiles = makeConfigFiles {
+  configFiles = makeSetupConfigFiles {
     inherit (package) identifier;
     inherit fullName flags;
     component = {