Fix using lld in shell-for

Before we didn't actually include lld in the environment.
Let's add that to the nativeBuildInputs if the compiler is using lld.

Author: TeofilC

builder/default.nix

@@ -80,7 +80,7 @@ let
   # Same as haskellPackages.shellFor in nixpkgs.
   shellFor = haskellLib.weakCallPackage pkgs ./shell-for.nix {
     inherit hsPkgs ghcForComponent makeConfigFiles hoogleLocal haskellLib pkgsBuildBuild evalPackages compiler ghc;
-    inherit (buildPackages) glibcLocales;
+    inherit (buildPackages) glibcLocales llvmPackages;
   };
 
   # Same as haskellPackages.ghcWithPackages and ghcWithHoogle in nixpkgs.

builder/shell-for.nix

@@ -1,4 +1,4 @@
-{ lib, stdenv, mkShell, glibcLocales, ghcForComponent, makeConfigFiles, hsPkgs, hoogleLocal, haskellLib, pkgsBuildBuild, evalPackages, compiler, haskell-nix, ghc }:
+{ lib, stdenv, mkShell, glibcLocales, ghcForComponent, makeConfigFiles, hsPkgs, hoogleLocal, haskellLib, pkgsBuildBuild, evalPackages, compiler, haskell-nix, ghc, llvmPackages }:
 
 { # `packages` function selects packages that will be worked on in the shell itself.
   # These packages will not be built by `shellFor`, but their
@@ -175,6 +175,7 @@ in
       ++ nativeBuildInputs
       ++ mkDrvArgs.nativeBuildInputs or []
       ++ lib.attrValues (pkgsBuildBuild.haskell-nix.tools' evalPackages compiler.nix-name tools)
+      ++ lib.optional (ghcEnv.baseGhc.useLdLld or false) llvmPackages.bintools
       # If this shell is a cross compilation shell include
       # wrapper script for running cabal build with appropriate args.
       # Includes `--with-compiler` in case the `cabal.project` file has `with-compiler:` in it.