haskell infra: Fix cross as much as possible without changing hashes

pkgs/development/haskell-modules/generic-builder.nix

@@ -1,7 +1,14 @@
-{ stdenv, fetchurl, ghc, pkgconfig, glibcLocales, coreutils, gnugrep, gnused
-, jailbreak-cabal, hscolour, cpphs, nodejs, lib, removeReferencesTo
+{ stdenv, buildPackages, ghc
+, jailbreak-cabal, hscolour, cpphs, nodejs
+, buildPlatform, hostPlatform
 }:
-let isCross = (ghc.cross or null) != null; in
+
+let
+  isCross = buildPlatform != hostPlatform;
+  inherit (buildPackages)
+    fetchurl removeReferencesTo
+    pkgconfig coreutils gnugrep gnused glibcLocales;
+in
 
 { pname
 , dontStrip ? (ghc.isGhcjs or false)
@@ -20,8 +27,8 @@ let isCross = (ghc.cross or null) != null; in
 , enableLibraryProfiling ? false
 , enableExecutableProfiling ? false
 # TODO enable shared libs for cross-compiling
-, enableSharedExecutables ? !isCross && (((ghc.isGhcjs or false) || stdenv.lib.versionOlder "7.7" ghc.version))
-, enableSharedLibraries ? !isCross && (((ghc.isGhcjs or false) || stdenv.lib.versionOlder "7.7" ghc.version))
+, enableSharedExecutables ? ((ghc.isGhcjs or false) || stdenv.lib.versionOlder "7.7" ghc.version)
+, enableSharedLibraries ? ((ghc.isGhcjs or false) || stdenv.lib.versionOlder "7.7" ghc.version)
 , enableSplitObjs ? null # OBSOLETE, use enableDeadCodeElimination
 , enableDeadCodeElimination ? (!stdenv.isDarwin)  # TODO: use -dead_strip  for darwin
 , enableStaticLibraries ? true
@@ -53,7 +60,7 @@ let isCross = (ghc.cross or null) != null; in
 , shellHook ? ""
 , coreSetup ? false # Use only core packages to build Setup.hs.
 , useCpphs ? false
-, hardeningDisable ? lib.optional (ghc.isHaLVM or false) "all"
+, hardeningDisable ? stdenv.lib.optional (ghc.isHaLVM or false) "all"
 , enableSeparateDataOutput ? false
 , enableSeparateDocOutput ? doHaddock
 } @ args:
@@ -102,10 +109,10 @@ let
   enableParallelBuilding = (versionOlder "7.8" ghc.version && !hasActiveLibrary) || versionOlder "8.0.1" ghc.version;
 
   crossCabalFlags = [
-    "--with-ghc=${ghc.cross.config}-ghc"
-    "--with-ghc-pkg=${ghc.cross.config}-ghc-pkg"
-    "--with-gcc=${ghc.cc}"
-    "--with-ld=${ghc.ld}"
+    "--with-ghc=${ghc.targetPrefix}ghc"
+    "--with-ghc-pkg=${ghc.targetPrefix}ghc-pkg"
+    "--with-gcc=${stdenv.cc}/bin/${stdenv.cc.targetPrefix}cc"
+    "--with-ld=${stdenv.cc.bintools}/bin/${stdenv.cc.bintools.targetPrefix}ld"
     "--with-hsc2hs=${nativeGhc}/bin/hsc2hs"
   ] ++ (if isHaLVM then [] else ["--hsc2hs-options=--cross-compile"]);
 
@@ -135,7 +142,7 @@ let
   ] ++ optionals isGhcjs [
     "--ghcjs"
   ] ++ optionals isCross ([
-    "--configure-option=--host=${ghc.cross.config}"
+    "--configure-option=--host=${hostPlatform.config}"
   ] ++ crossCabalFlags);
 
   setupCompileFlags = [
@@ -171,8 +178,7 @@ let
   setupBuilder = if isCross then "${nativeGhc}/bin/ghc" else ghcCommand;
   setupCommand = "./Setup";
   ghcCommand' = if isGhcjs then "ghcjs" else "ghc";
-  crossPrefix = if (ghc.cross or null) != null then "${ghc.cross.config}-" else "";
-  ghcCommand = "${crossPrefix}${ghcCommand'}";
+  ghcCommand = "${ghc.targetPrefix}${ghcCommand'}";
   ghcCommandCaps= toUpper ghcCommand';
 
 in
@@ -269,6 +275,8 @@ stdenv.mkDerivation ({
     runHook postCompileBuildDriver
   '';
 
+  inherit configureFlags;
+
   configurePhase = ''
     runHook preConfigure
 
@@ -402,7 +410,6 @@ stdenv.mkDerivation ({
 // optionalAttrs (postCompileBuildDriver != "") { inherit postCompileBuildDriver; }
 // optionalAttrs (preUnpack != "")      { inherit preUnpack; }
 // optionalAttrs (postUnpack != "")     { inherit postUnpack; }
-// optionalAttrs (configureFlags != []) { inherit configureFlags; }
 // optionalAttrs (patches != [])        { inherit patches; }
 // optionalAttrs (patchPhase != "")     { inherit patchPhase; }
 // optionalAttrs (preConfigure != "")   { inherit preConfigure; }
@@ -421,5 +428,5 @@ stdenv.mkDerivation ({
 // optionalAttrs (postFixup != "")      { inherit postFixup; }
 // optionalAttrs (dontStrip)            { inherit dontStrip; }
 // optionalAttrs (hardeningDisable != []) { inherit hardeningDisable; }
-// optionalAttrs (stdenv.isLinux)       { LOCALE_ARCHIVE = "${glibcLocales}/lib/locale/locale-archive"; }
+// optionalAttrs (buildPlatform.isLinux){ LOCALE_ARCHIVE = "${glibcLocales}/lib/locale/locale-archive"; }
 )

pkgs/development/haskell-modules/make-package-set.nix

@@ -1,7 +1,10 @@
 # This expression takes a file like `hackage-packages.nix` and constructs
 # a full package set out of that.
 
-{ # package-set used for non-haskell dependencies (all of nixpkgs)
+{ # package-set used for build tools (all of nixpkgs)
+  buildPackages
+
+, # package-set used for non-haskell dependencies (all of nixpkgs)
   pkgs
 
 , # stdenv to use for building haskell packages
@@ -28,19 +31,21 @@
 self:
 
 let
+  inherit (stdenv) buildPlatform hostPlatform;
 
   inherit (stdenv.lib) fix' extends makeOverridable;
   inherit (haskellLib) overrideCabal;
 
+  buildHaskellPackages = if hostPlatform != buildPlatform
+                         then self.ghc.bootPkgs
+                         else self;
+
   mkDerivationImpl = pkgs.callPackage ./generic-builder.nix {
     inherit stdenv;
-    inherit (pkgs) fetchurl pkgconfig glibcLocales coreutils gnugrep gnused;
-    nodejs = pkgs.nodejs-slim;
-    jailbreak-cabal = if (self.ghc.cross or null) != null
-      then self.ghc.bootPkgs.jailbreak-cabal
-      else self.jailbreak-cabal;
+    nodejs = buildPackages.nodejs-slim;
+    inherit (buildHaskellPackages) jailbreak-cabal;
     inherit (self) ghc;
-    hscolour = overrideCabal self.hscolour (drv: {
+    hscolour = overrideCabal buildHaskellPackages.hscolour (drv: {
       isLibrary = false;
       doHaddock = false;
       hyperlinkSource = false;      # Avoid depending on hscolour for this build.
@@ -104,13 +109,13 @@ let
   haskellSrc2nix = { name, src, sha256 ? null }:
     let
       sha256Arg = if isNull sha256 then "--sha256=" else ''--sha256="${sha256}"'';
-    in pkgs.stdenv.mkDerivation {
+    in pkgs.buildPackages.stdenv.mkDerivation {
       name = "cabal2nix-${name}";
-      buildInputs = [ pkgs.haskellPackages.cabal2nix ];
+      nativeBuildInputs = [ pkgs.buildPackages.haskellPackages.cabal2nix ];
       preferLocalBuild = true;
       phases = ["installPhase"];
       LANG = "en_US.UTF-8";
-      LOCALE_ARCHIVE = pkgs.lib.optionalString pkgs.stdenv.isLinux "${pkgs.glibcLocales}/lib/locale/locale-archive";
+      LOCALE_ARCHIVE = pkgs.lib.optionalString buildPlatform.isLinux "${buildPackages.glibcLocales}/lib/locale/locale-archive";
       installPhase = ''
         export HOME="$TMP"
         mkdir -p "$out"

pkgs/development/haskell-modules/with-packages-wrapper.nix

@@ -36,9 +36,8 @@ let
   isHaLVM       = ghc.isHaLVM or false;
   ghc761OrLater = isGhcjs || isHaLVM || lib.versionOlder "7.6.1" ghc.version;
   packageDBFlag = if ghc761OrLater then "--global-package-db" else "--global-conf";
-  ghcCommand'   = if isGhcjs then "ghcjs" else "ghc";
-  crossPrefix = if (ghc.cross or null) != null then "${ghc.cross.config}-" else "";
-  ghcCommand = "${crossPrefix}${ghcCommand'}";
+  ghcCommand'    = if isGhcjs then "ghcjs" else "ghc";
+  ghcCommand = "${ghc.targetPrefix}${ghcCommand'}";
   ghcCommandCaps= lib.toUpper ghcCommand';
   libDir        = if isHaLVM then "$out/lib/HaLVM-${ghc.version}" else "$out/lib/${ghcCommand}-${ghc.version}";
   docDir        = "$out/share/doc/ghc/html";

pkgs/os-specific/darwin/ghc-standalone-archive/default.nix

@@ -2,8 +2,7 @@
 { haskellPackages, src, deps ? p : [], name }: let
   inherit (haskellPackages) ghc ghcWithPackages;
   with-env = ghcWithPackages deps;
-  crossPrefix = if (ghc.cross or null) != null then "${ghc.cross.config}-" else "";
-  ghcName = "${crossPrefix}ghc";
+  ghcName = "${ghc.targetPrefix}ghc";
 in runCommand name { buildInputs = [ with-env cctools ]; } ''
   mkdir -p $out/lib
   mkdir -p $out/include