Add enableDWARF and useLLVM

builder/comp-builder.nix

@@ -61,6 +61,10 @@ let self =
 
 # Debug
 , enableDebugRTS ? false
+, enableDWARF ? false
+
+# LLVM
+, useLLVM ? ghc.useLLVM
 }@drvArgs:
 
 let
@@ -139,6 +143,10 @@ let
       ++ configureFlags
       ++ (ghc.extraConfigureFlags or [])
       ++ lib.optional enableDebugRTS "--ghc-option=-debug"
+      ++ lib.optional enableDWARF "--ghc-option=-g"
+      ++ lib.optionals useLLVM [
+        "--ghc-option=-fPIC" "--gcc-option=-fPIC"
+        ]
     );
 
   setupGhcOptions = lib.optional (package.ghcOptions != null) '' --ghc-options="${package.ghcOptions}"'';

compiler/ghc/default.nix

@@ -305,6 +305,7 @@ stdenv.mkDerivation (rec {
 
     inherit llvmPackages;
     inherit enableShared;
+    inherit useLLVM;
 
     # Our Cabal compiler name
     haskellCompilerName = "ghc-${version}";

overlays/bootstrap.nix

@@ -362,6 +362,7 @@ in {
                 # with the current use of env and exact Deps.
                 (builtins.mapAttrs
                     (_: v: v // {
+                        useLLVM = false;
                         isHaskellNixBootCompiler = true;
                     })
           ({
@@ -571,6 +572,7 @@ in {
             v.overrideAttrs (drv: {
               postInstall = (drv.postInstall or "") + installDeps "";
             }) // {
+              useLLVM = false;
               isHaskellNixBootCompiler = true;
             }
           )