Fix GHCJS 8.4/8.2 in sandboxed builds (#41411)

pkgs/development/compilers/ghcjs-ng/configured-ghcjs-src.nix

@@ -6,6 +6,8 @@
 , cabal-install
 , gmp
 , runCommand
+, lib
+, stdenv
 
 , ghc
 , happy
@@ -20,15 +22,18 @@ runCommand "configured-ghcjs-src" {
     autoconf
     automake
     python3
-    gcc
     ghc
     happy
     alex
     cabal-install
+  ] ++ lib.optionals stdenv.isDarwin [
+    gcc # https://github.com/ghcjs/ghcjs/issues/663
   ];
   inherit ghcjsSrc;
 } ''
   export HOME=$(pwd)
+  mkdir $HOME/.cabal
+  touch $HOME/.cabal/config
   cp -r "$ghcjsSrc" "$out"
   chmod -R +w "$out"
   cd "$out"

pkgs/development/compilers/ghcjs-ng/default.nix

@@ -50,13 +50,10 @@ let
   };
 
   bootGhcjs = haskellLib.justStaticExecutables passthru.bootPkgs.ghcjs;
-  libexec =
+  libexec = "${bootGhcjs}/libexec/${builtins.replaceStrings ["darwin"] ["osx"] stdenv.system}-${passthru.bootPkgs.ghc.name}/${bootGhcjs.name}";
-    if builtins.compareVersions bootGhcjs.version "8.3" <= 0
-      then "${bootGhcjs}/bin"
-      else "${bootGhcjs}/libexec/${builtins.replaceStrings ["darwin"] ["osx"] stdenv.system}-${passthru.bootPkgs.ghc.name}/${bootGhcjs.name}";
 
 in stdenv.mkDerivation {
-    name = "ghcjs";
+    name = bootGhcjs.name;
     src = passthru.configuredSrc;
     nativeBuildInputs = [
       bootGhcjs
@@ -73,6 +70,8 @@ in stdenv.mkDerivation {
     phases = ["unpackPhase" "buildPhase"];
     buildPhase = ''
       export HOME=$TMP
+      mkdir $HOME/.cabal
+      touch $HOME/.cabal/config
       cd lib/boot
 
       mkdir -p $out/bin