treewide: Do a number of no-op cleanups for cross and darwin

I am taking the non-invasive parts of #110914 to hopefully help out with #111988.

In particular:

 - Use `lib.makeScopeWithSplicing` to make the `darwin` package set have
   a proper `callPackage`.

 - Adjust Darwin `stdenv`'s overlays keeping things from the previous
   stage to not stick around too much.

 - Expose `binutilsNoLibc` / `darwin.binutilsNoLibc` to hopefully get us
   closer to a unified LLVM and GCC bootstrap.

7 files changed, 111 insertions, 83 deletions

diff --git a/lib/customisation.nix b/lib/customisation.nix
index 37a7951896b..c17cb0d0f8e 100644
--- a/lib/customisation.nix
+++ b/lib/customisation.nix
@@ -219,16 +219,17 @@ rec {
 
   /* Like the above, but aims to support cross compilation. It's still ugly, but
      hopefully it helps a little bit. */
-  makeScopeWithSplicing = splicePackages: newScope: otherSplices: keep: f:
+  makeScopeWithSplicing = splicePackages: newScope: otherSplices: keep: extra: f:
     let
-      spliced = splicePackages {
+      spliced0 = splicePackages {
         pkgsBuildBuild = otherSplices.selfBuildBuild;
         pkgsBuildHost = otherSplices.selfBuildHost;
         pkgsBuildTarget = otherSplices.selfBuildTarget;
         pkgsHostHost = otherSplices.selfHostHost;
         pkgsHostTarget = self; # Not `otherSplices.selfHostTarget`;
         pkgsTargetTarget = otherSplices.selfTargetTarget;
-      } // keep self;
+      };
+      spliced = extra spliced0 // spliced0 // keep self;
       self = f self // {
         newScope = scope: newScope (spliced // scope);
         callPackage = newScope spliced; # == self.newScope {};
@@ -239,6 +240,7 @@ rec {
           newScope
           otherSplices
           keep
+          extra
           (lib.fixedPoints.extends g f);
         packages = f;
       };
diff --git a/pkgs/development/interpreters/python/default.nix b/pkgs/development/interpreters/python/default.nix
index d74e017d830..5f13418aa58 100644
--- a/pkgs/development/interpreters/python/default.nix
+++ b/pkgs/development/interpreters/python/default.nix
@@ -69,6 +69,7 @@ with pkgs;
               recursivePthLoader
             ;
           };
+          extra = _: {};
           optionalExtensions = cond: as: if cond then as else [];
           python2Extension = import ../../../top-level/python2-packages.nix;
           extensions = lib.composeManyExtensions ((optionalExtensions (!self.isPy3k) [python2Extension]) ++ [ overrides ]);
@@ -77,6 +78,7 @@ with pkgs;
           pkgs.newScope
           otherSplices
           keep
+          extra
           (lib.extends extensions pythonPackagesFun))
         {
           overrides = packageOverrides;
diff --git a/pkgs/os-specific/darwin/apple-source-releases/default.nix b/pkgs/os-specific/darwin/apple-source-releases/default.nix
index 23434931542..3e431810f20 100644
--- a/pkgs/os-specific/darwin/apple-source-releases/default.nix
+++ b/pkgs/os-specific/darwin/apple-source-releases/default.nix
@@ -1,9 +1,6 @@
-{ lib, stdenv, fetchurl, fetchzip, pkgs }:
+{ lib, stdenv, stdenvNoCC, fetchurl, fetchzip, pkgs }:
 
 let
-  macosPackages_11_0_1 = import ./macos-11.0.1.nix { inherit applePackage'; };
-  developerToolsPackages_11_3_1 = import ./developer-tools-11.3.1.nix { inherit applePackage'; };
-
   # This attrset can in theory be computed automatically, but for that to work nicely we need
   # import-from-derivation to work properly. Currently it's rather ugly when we try to bootstrap
   # a stdenv out of something like this. With some care we can probably get rid of this, but for
@@ -190,17 +187,6 @@ let
     }) // (attrs.meta or {});
   });
 
-  applePackage' = namePath: version: sdkName: sha256: let
-    pname = builtins.head (lib.splitString "/" namePath);
-    appleDerivation = appleDerivation' pname version sdkName sha256;
-    callPackage = pkgs.newScope (packages // pkgs.darwin // { inherit appleDerivation; });
-  in callPackage (./. + "/${namePath}");
-
-  applePackage = namePath: sdkName: sha256: let
-    pname = builtins.head (lib.splitString "/" namePath);
-    version = versions.${sdkName}.${pname};
-  in applePackage' namePath version sdkName sha256;
-
   IOKitSpecs = {
     IOAudioFamily                        = fetchApple "osx-10.10.5" "0ggq7za3iq8g02j16rj67prqhrw828jsw3ah3bxq8a1cvr55aqnq";
     IOFireWireFamily                     = fetchApple "osx-10.10.5" "059qa1m668kwvchl90cqcx35b31zaqdg61zi11y1imn5s389y2g1";
@@ -225,11 +211,35 @@ let
 
   IOKitSrcs = lib.mapAttrs (name: value: if lib.isFunction value then value name else value) IOKitSpecs;
 
+in
+
+# darwin package set
+self:
+
+let
+  macosPackages_11_0_1 = import ./macos-11.0.1.nix { inherit applePackage'; };
+  developerToolsPackages_11_3_1 = import ./developer-tools-11.3.1.nix { inherit applePackage'; };
+
+  applePackage' = namePath: version: sdkName: sha256:
+    let
+      pname = builtins.head (lib.splitString "/" namePath);
+      appleDerivation = appleDerivation' pname version sdkName sha256;
+      callPackage = self.newScope { inherit appleDerivation; };
+    in callPackage (./. + "/${namePath}");
+
+  applePackage = namePath: sdkName: sha256: let
+    pname = builtins.head (lib.splitString "/" namePath);
+    version = versions.${sdkName}.${pname};
+  in applePackage' namePath version sdkName sha256;
+
   # Only used for bootstrapping. It’s convenient because it was the last version to come with a real makefile.
   adv_cmds-boot = applePackage "adv_cmds/boot.nix" "osx-10.5.8" "102ssayxbg9wb35mdmhswbnw0bg7js3pfd8fcbic83c5q3bqa6c6" {};
 
-  # TODO: shorten this list, we should cut down to a minimum set of bootstrap or necessary packages here.
-  stubPackages = {
+in
+
+developerToolsPackages_11_3_1 // macosPackages_11_0_1 // {
+    # TODO: shorten this list, we should cut down to a minimum set of bootstrap or necessary packages here.
+
     inherit (adv_cmds-boot) ps locale;
     architecture    = applePackage "architecture"      "osx-10.11.6"     "1pbpjcd7is69hn8y29i98ci0byik826if8gnp824ha92h90w0fq3" {};
     bsdmake         = applePackage "bsdmake"           "dev-tools-3.2.6" "11a9kkhz5bfgi1i8kpdkis78lhc6b5vxmhd598fcdgra1jw4iac2" {};
@@ -290,7 +300,4 @@ let
     # TODO(matthewbauer):
     # To be removed, once I figure out how to build a newer Security version.
     Security        = applePackage "Security/boot.nix" "osx-10.9.5"      "1nv0dczf67dhk17hscx52izgdcyacgyy12ag0jh6nl5hmfzsn8yy" {};
-  };
-
-  packages = developerToolsPackages_11_3_1 // macosPackages_11_0_1 // stubPackages;
-in packages
+}
diff --git a/pkgs/stdenv/darwin/default.nix b/pkgs/stdenv/darwin/default.nix
index 227f53b02cc..fcfab9bff5d 100644
--- a/pkgs/stdenv/darwin/default.nix
+++ b/pkgs/stdenv/darwin/default.nix
@@ -176,13 +176,13 @@ in rec {
         '';
       };
 
-      darwin = super.darwin // {
+      darwin = super.darwin.overrideScope (selfDarwin: superDarwin: {
         Libsystem = stdenv.mkDerivation {
           name = "bootstrap-stage0-Libsystem";
           buildCommand = ''
             mkdir -p $out
 
-            cp -r ${self.darwin.darwin-stubs}/usr/lib $out/lib
+            cp -r ${selfDarwin.darwin-stubs}/usr/lib $out/lib
             chmod -R +w $out/lib
             substituteInPlace $out/lib/libSystem.B.tbd --replace /usr/lib/system $out/lib/system
 
@@ -201,7 +201,7 @@ in rec {
           '';
         };
 
-        darwin-stubs = super.darwin.darwin-stubs.override { inherit (self) stdenv fetchurl; };
+        darwin-stubs = superDarwin.darwin-stubs.override { inherit (self) stdenv fetchurl; };
 
         dyld = {
           name = "bootstrap-stage0-dyld";
@@ -220,10 +220,10 @@ in rec {
           nativeTools  = false;
           nativeLibc   = false;
           inherit (self) buildPackages coreutils gnugrep;
-          libc         = self.pkgs.darwin.Libsystem;
+          libc         = selfDarwin.Libsystem;
           bintools     = { name = "bootstrap-stage0-binutils"; outPath = bootstrapTools; };
         };
-      };
+      });
 
       llvmPackages_7 = {
         clang-unwrapped = stdenv.mkDerivation {
@@ -291,12 +291,12 @@ in rec {
         });
       in { inherit tools libraries; } // tools // libraries);
 
-      darwin = super.darwin // {
+      darwin = super.darwin.overrideScope (selfDarwin: _: {
         binutils = darwin.binutils.override {
           coreutils = self.coreutils;
-          libc = self.darwin.Libsystem;
+          libc = selfDarwin.Libsystem;
         };
-      };
+      });
     };
   in with prevStage; stageFun 1 prevStage {
     extraPreHook = "export NIX_CFLAGS_COMPILE+=\" -F${bootstrapTools}/Library/Frameworks\"";
@@ -337,11 +337,11 @@ in rec {
         });
       in { inherit tools libraries; } // tools // libraries);
 
-      darwin = super.darwin // {
+      darwin = super.darwin.overrideScope (_: _: {
         inherit (darwin)
           binutils dyld Libsystem xnu configd ICU libdispatch libclosure
           launchd CF darwin-stubs;
-      };
+      });
     };
   in with prevStage; stageFun 2 prevStage {
     extraPreHook = ''
@@ -382,11 +382,11 @@ in rec {
         });
       in { inherit libraries; } // libraries);
 
-      darwin = super.darwin // {
+      darwin = super.darwin.overrideScope (_: _: {
         inherit (darwin)
           dyld Libsystem xnu configd libdispatch libclosure launchd libiconv
           locale darwin-stubs;
-      };
+      });
     };
   in with prevStage; stageFun 3 prevStage {
     shell = "${pkgs.bash}/bin/bash";
@@ -442,14 +442,14 @@ in rec {
         });
       in { inherit tools libraries; } // tools // libraries);
 
-      darwin = super.darwin // rec {
+      darwin = super.darwin.overrideScope (_: superDarwin: {
         inherit (darwin) dyld Libsystem libiconv locale darwin-stubs;
 
-        CF = super.darwin.CF.override {
+        CF = superDarwin.CF.override {
           inherit libxml2;
           python3 = prevStage.python3;
         };
-      };
+      });
     };
   in with prevStage; stageFun 4 prevStage {
     shell = "${pkgs.bash}/bin/bash";
@@ -480,11 +480,11 @@ in rec {
         });
       in { inherit tools libraries; } // tools // libraries);
 
-      darwin = super.darwin // {
+      darwin = super.darwin.overrideScope (_: _: {
         inherit (darwin) dyld ICU Libsystem libiconv;
       } // lib.optionalAttrs (super.stdenv.targetPlatform == localSystem) {
         inherit (darwin) binutils binutils-unwrapped cctools;
-      };
+      });
     } // lib.optionalAttrs (super.stdenv.targetPlatform == localSystem) {
       # Need to get rid of these when cross-compiling.
       inherit binutils binutils-unwrapped;
@@ -537,14 +537,14 @@ in rec {
     ]);
 
     overrides = lib.composeExtensions persistent (self: super: {
+      darwin = super.darwin.overrideScope (_: superDarwin: {
+        inherit (prevStage.darwin) CF darwin-stubs;
+        xnu = superDarwin.xnu.override { inherit (prevStage) python3; };
+      });
+    } // lib.optionalAttrs (super.stdenv.targetPlatform == localSystem) {
       clang = cc;
       llvmPackages = super.llvmPackages // { clang = cc; };
       inherit cc;
-
-      darwin = super.darwin // {
-        inherit (prevStage.darwin) CF darwin-stubs;
-        xnu = super.darwin.xnu.override { inherit (prevStage) python3; };
-      };
     });
   };
 
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 63de087f73f..e2fc45fe5c4 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -10395,15 +10395,7 @@ in
   # The GCC used to build libc for the target platform. Normal gccs will be
   # built with, and use, that cross-compiled libc.
   gccCrossStageStatic = assert stdenv.targetPlatform != stdenv.hostPlatform; let
-    libcCross1 =
-      if stdenv.targetPlatform.libc == "msvcrt" then targetPackages.windows.mingw_w64_headers
-      else if stdenv.targetPlatform.libc == "libSystem" then darwin.xcode
-      else if stdenv.targetPlatform.libc == "nblibc" then netbsd.headers
-      else null;
-    binutils1 = wrapBintoolsWith {
-      bintools = binutils-unwrapped;
-      libc = libcCross1;
-    };
+    libcCross1 = binutilsNoLibc.libc;
     in wrapCCWith {
       cc = gccFun {
         # copy-pasted
@@ -10416,10 +10408,10 @@ in
         crossStageStatic = true;
         langCC = false;
         libcCross = libcCross1;
-        targetPackages.stdenv.cc.bintools = binutils1;
+        targetPackages.stdenv.cc.bintools = binutilsNoLibc;
         enableShared = false;
       };
-      bintools = binutils1;
+      bintools = binutilsNoLibc;
       libc = libcCross1;
       extraPackages = [];
   };
@@ -12532,6 +12524,14 @@ in
       gold = false;
     };
   });
+  binutilsNoLibc = wrapBintoolsWith {
+    bintools = binutils-unwrapped;
+    libc =
+      /**/ if stdenv.targetPlatform.libc == "msvcrt" then targetPackages.windows.mingw_w64_headers
+      else if stdenv.targetPlatform.libc == "libSystem" then darwin.xcode
+      else if stdenv.targetPlatform.libc == "nblibc" then targetPackages.netbsdCross.headers
+      else null;
+  };
 
   bison = callPackage ../development/tools/parsing/bison { };
 
diff --git a/pkgs/top-level/darwin-packages.nix b/pkgs/top-level/darwin-packages.nix
index 3ece95c5845..5275a6f3123 100644
--- a/pkgs/top-level/darwin-packages.nix
+++ b/pkgs/top-level/darwin-packages.nix
@@ -1,27 +1,44 @@
-{ buildPackages, pkgs, targetPackages
-, darwin, stdenv, callPackage, callPackages, newScope
+{ lib
+, buildPackages, pkgs, targetPackages
+, pkgsBuildBuild, pkgsBuildHost, pkgsBuildTarget, pkgsHostHost, pkgsTargetTarget
+, stdenv, splicePackages, newScope
 }:
 
 let
-  apple-source-releases = callPackage ../os-specific/darwin/apple-source-releases { };
+  otherSplices = {
+    selfBuildBuild = pkgsBuildBuild.darwin;
+    selfBuildHost = pkgsBuildHost.darwin;
+    selfBuildTarget = pkgsBuildTarget.darwin;
+    selfHostHost = pkgsHostHost.darwin;
+    selfTargetTarget = pkgsTargetTarget.darwin or {}; # might be missing
+  };
 
-  impure-cmds = callPackage ../os-specific/darwin/impure-cmds { };
 in
 
-(impure-cmds // apple-source-releases // {
+lib.makeScopeWithSplicing splicePackages newScope otherSplices (_: {}) (spliced: spliced.apple_sdk.frameworks) (self: let
+  inherit (self) mkDerivation callPackage;
 
-  callPackage = newScope (darwin.apple_sdk.frameworks // darwin);
+  # Must use pkgs.callPackage to avoid infinite recursion.
 
-  stdenvNoCF = stdenv.override {
-    extraBuildInputs = [];
+  apple-source-releases = pkgs.callPackage ../os-specific/darwin/apple-source-releases { } self;
+
+  impure-cmds = pkgs.callPackage ../os-specific/darwin/impure-cmds { };
+
+  apple_sdk = pkgs.callPackage ../os-specific/darwin/apple-sdk {
+    inherit (buildPackages.darwin) print-reexports;
+    inherit (self) darwin-stubs;
   };
+in
+
+impure-cmds // apple-source-releases // {
 
-  apple_sdk = callPackage ../os-specific/darwin/apple-sdk {
-    inherit (darwin) darwin-stubs print-reexports;
+  inherit apple_sdk;
+
+  stdenvNoCF = stdenv.override {
+    extraBuildInputs = [];
   };
 
   binutils-unwrapped = callPackage ../os-specific/darwin/binutils {
-    inherit (darwin) cctools;
     inherit (pkgs) binutils-unwrapped;
     inherit (pkgs.llvmPackages_7) llvm clang-unwrapped;
   };
@@ -31,17 +48,21 @@ in
       if stdenv.targetPlatform != stdenv.hostPlatform
       then pkgs.libcCross
       else pkgs.stdenv.cc.libc;
-    bintools = darwin.binutils-unwrapped;
+    bintools = self.binutils-unwrapped;
+  };
+
+  binutilsNoLibc = pkgs.wrapBintoolsWith {
+    libc = null;
+    bintools = self.binutils-unwrapped;
   };
 
   cctools = callPackage ../os-specific/darwin/cctools/port.nix {
-    inherit (darwin) libobjc maloader libtapi;
     stdenv = if stdenv.isDarwin then stdenv else pkgs.libcxxStdenv;
     libcxxabi = pkgs.libcxxabi;
   };
 
   # TODO: remove alias.
-  cf-private = darwin.apple_sdk.frameworks.CoreFoundation;
+  cf-private = self.apple_sdk.frameworks.CoreFoundation;
 
   DarwinTools = callPackage ../os-specific/darwin/DarwinTools { };
 
@@ -50,15 +71,13 @@ in
   print-reexports = callPackage ../os-specific/darwin/apple-sdk/print-reexports { };
 
   maloader = callPackage ../os-specific/darwin/maloader {
-    inherit (darwin) opencflite;
   };
 
   insert_dylib = callPackage ../os-specific/darwin/insert_dylib { };
 
-  iosSdkPkgs = darwin.callPackage ../os-specific/darwin/xcode/sdk-pkgs.nix {
+  iosSdkPkgs = callPackage ../os-specific/darwin/xcode/sdk-pkgs.nix {
     buildIosSdk = buildPackages.darwin.iosSdkPkgs.sdk;
     targetIosSdkPkgs = targetPackages.darwin.iosSdkPkgs;
-    xcode = darwin.xcode;
     inherit (pkgs.llvmPackages) clang-unwrapped;
   };
 
@@ -70,13 +89,13 @@ in
 
   opencflite = callPackage ../os-specific/darwin/opencflite { };
 
-  stubs = callPackages ../os-specific/darwin/stubs { };
+  stubs = pkgs.callPackages ../os-specific/darwin/stubs { };
 
-  trash = darwin.callPackage ../os-specific/darwin/trash { };
+  trash = callPackage ../os-specific/darwin/trash { };
 
   usr-include = callPackage ../os-specific/darwin/usr-include { };
 
-  inherit (callPackages ../os-specific/darwin/xcode { })
+  inherit (pkgs.callPackages ../os-specific/darwin/xcode { })
     xcode_8_1 xcode_8_2
     xcode_9_1 xcode_9_2 xcode_9_4 xcode_9_4_1
     xcode_10_2 xcode_10_2_1 xcode_10_3
@@ -85,10 +104,10 @@ in
 
   CoreSymbolication = callPackage ../os-specific/darwin/CoreSymbolication { };
 
-  CF = callPackage ../os-specific/darwin/swift-corelibs/corefoundation.nix { inherit (darwin) objc4 ICU; };
+  CF = callPackage ../os-specific/darwin/swift-corelibs/corefoundation.nix { };
 
   # As the name says, this is broken, but I don't want to lose it since it's a direction we want to go in
-  # libdispatch-broken = callPackage ../os-specific/darwin/swift-corelibs/libdispatch.nix { inherit (darwin) apple_sdk_sierra xnu; };
+  # libdispatch-broken = callPackage ../os-specific/darwin/swift-corelibs/libdispatch.nix { };
 
   darling = callPackage ../os-specific/darwin/darling/default.nix { };
 
@@ -96,8 +115,6 @@ in
 
   ios-deploy = callPackage ../os-specific/darwin/ios-deploy {};
 
-  discrete-scroll = callPackage ../os-specific/darwin/discrete-scroll {
-    inherit (darwin.apple_sdk.frameworks) Cocoa;
-  };
+  discrete-scroll = callPackage ../os-specific/darwin/discrete-scroll { };
 
 })
diff --git a/pkgs/top-level/static.nix b/pkgs/top-level/static.nix
index e73eba8e142..32559c0e799 100644
--- a/pkgs/top-level/static.nix
+++ b/pkgs/top-level/static.nix
@@ -25,7 +25,7 @@ self: super: let
   }; in stdenv // {
     mkDerivation = args: stdenv.mkDerivation (args // {
       NIX_CFLAGS_LINK = toString (args.NIX_CFLAGS_LINK or "")
-                      + optionalString stdenv.cc.isGNU " -static-libgcc";
+                      + optionalString (stdenv_.cc.isGNU or false) " -static-libgcc";
       nativeBuildInputs = (args.nativeBuildInputs or []) ++ [ (makeSetupHook {
         substitutions = {
           libsystem = "${stdenv.cc.libc}/lib/libSystem.B.dylib";