haskell.compiler.ghc*: set stage 0 tools

This is easy in comparison since these tools won't end up in GHC's
settings nor need to be available at runtime, so we can use
the *_FOR_BUILD environment variables.

It is important to add buildCC to depsBuildBuild to engage the
stdenv/wrapper script machinery properly.

Co-authored-by: sternenseemann <sternenseemann@systemli.org>

pkgs/development/compilers/ghc/8.10.7.nix

@@ -1,4 +1,4 @@
-{ lib, stdenv, pkgsBuildTarget, pkgsHostTarget, targetPackages
+{ lib, stdenv, pkgsBuildTarget, pkgsHostTarget, buildPackages, targetPackages
 
 # build-tools
 , bootPkgs
@@ -134,6 +134,7 @@ let
     pkgsBuildTarget.targetPackages.stdenv.cc
   ] ++ lib.optional useLLVM buildTargetLlvmPackages.llvm;
 
+  buildCC = buildPackages.stdenv.cc;
   targetCC = builtins.head toolsForTarget;
 
   # toolPath calculates the absolute path to the name tool associated with a
@@ -299,6 +300,10 @@ stdenv.mkDerivation (rec {
     # LLVM backend on Darwin needs clang: https://downloads.haskell.org/~ghc/latest/docs/html/users_guide/codegens.html#llvm-code-generator-fllvm
     export CLANG="${buildTargetLlvmPackages.clang}/bin/${buildTargetLlvmPackages.clang.targetPrefix}clang"
   '' + ''
+    # No need for absolute paths since these tools only need to work during the build
+    export CC_STAGE0="$CC_FOR_BUILD"
+    export LD_STAGE0="$LD_FOR_BUILD"
+    export AR_STAGE0="$AR_FOR_BUILD"
 
     echo -n "${buildMK}" > mk/build.mk
     sed -i -e 's|-isysroot /Developer/SDKs/MacOSX10.5.sdk||' configure
@@ -372,6 +377,10 @@ stdenv.mkDerivation (rec {
     sphinx
   ];
 
+  # Used by the STAGE0 compiler to build stage1
+  depsBuildBuild = [
+    buildCC
+  ];
   # For building runtime libs
   depsBuildTarget = toolsForTarget;
 

pkgs/development/compilers/ghc/common-hadrian.nix

@@ -12,6 +12,7 @@
 , stdenv
 , pkgsBuildTarget
 , pkgsHostTarget
+, buildPackages
 , targetPackages
 , fetchpatch
 
@@ -265,6 +266,7 @@ let
      else pkgsBuildTarget.targetPackages.stdenv.cc)
   ] ++ lib.optional useLLVM buildTargetLlvmPackages.llvm;
 
+  buildCC = buildPackages.stdenv.cc;
   targetCC = builtins.head toolsForTarget;
 
   # toolPath calculates the absolute path to the name tool associated with a
@@ -346,6 +348,10 @@ stdenv.mkDerivation ({
     for env in $(env | grep '^TARGET_' | sed -E 's|\+?=.*||'); do
       export "''${env#TARGET_}=''${!env}"
     done
+    # No need for absolute paths since these tools only need to work during the build
+    export CC_STAGE0="$CC_FOR_BUILD"
+    export LD_STAGE0="$LD_FOR_BUILD"
+    export AR_STAGE0="$AR_FOR_BUILD"
     # GHC is a bit confused on its cross terminology, as these would normally be
     # the *host* tools.
     export CC="${toolPath "cc" targetCC}"
@@ -484,6 +490,10 @@ stdenv.mkDerivation ({
 
   # For building runtime libs
   depsBuildTarget = toolsForTarget;
+  # Used by the STAGE0 compiler to build stage1
+  depsBuildBuild = [
+    buildCC
+  ];
 
   buildInputs = [ perl bash ] ++ (libDeps hostPlatform);
 

pkgs/development/compilers/ghc/common-make-native-bignum.nix

@@ -3,7 +3,7 @@
 , url ? "https://downloads.haskell.org/ghc/${version}/ghc-${version}-src.tar.xz"
 }:
 
-{ lib, stdenv, pkgsBuildTarget, pkgsHostTarget, targetPackages
+{ lib, stdenv, pkgsBuildTarget, pkgsHostTarget, buildPackages, targetPackages
 
 # build-tools
 , bootPkgs
@@ -134,6 +134,7 @@ let
     pkgsBuildTarget.targetPackages.stdenv.cc
   ] ++ lib.optional useLLVM buildTargetLlvmPackages.llvm;
 
+  buildCC = buildPackages.stdenv.cc;
   targetCC = builtins.head toolsForTarget;
 
   # toolPath calculates the absolute path to the name tool associated with a
@@ -305,6 +306,11 @@ stdenv.mkDerivation (rec {
     export CLANG="${buildTargetLlvmPackages.clang}/bin/${buildTargetLlvmPackages.clang.targetPrefix}clang"
   ''
   + ''
+    # No need for absolute paths since these tools only need to work during the build
+    export CC_STAGE0="$CC_FOR_BUILD"
+    export LD_STAGE0="$LD_FOR_BUILD"
+    export AR_STAGE0="$AR_FOR_BUILD"
+
     echo -n "${buildMK}" > mk/build.mk
   ''
   + lib.optionalString (lib.versionOlder version "9.2" || lib.versionAtLeast version "9.4") ''
@@ -393,6 +399,10 @@ stdenv.mkDerivation (rec {
     xattr
   ];
 
+  # Used by the STAGE0 compiler to build stage1
+  depsBuildBuild = [
+    buildCC
+  ];
   # For building runtime libs
   depsBuildTarget = toolsForTarget;