platforms.nix: Separate 32-bit and 64-bit PCs

With this, stdenv.platform.kernelArch can be used by the kernel builder
for PC platforms too.

Signed-off-by: Shea Levy <shea@shealevy.com>

pkgs/top-level/all-packages.nix

@@ -84,7 +84,9 @@ let
       if system == "armv6l-linux" then platforms.raspberrypi
       else if system == "armv5tel-linux" then platforms.sheevaplug
       else if system == "mips64el-linux" then platforms.fuloong2f_n32
-      else platforms.pc;
+      else if system == "x86_64-linux" then platforms.pc64
+      else if system == "i686-linux" then platforms.pc32
+      else platforms.pcBase;
 
   platform = if platform_ != null then platform_
     else config.platform or platformAuto;

pkgs/top-level/platforms.nix

@@ -1,15 +1,12 @@
 rec {
-  pc = {
+  pcBase = {
     name = "pc";
     uboot = null;
     kernelHeadersBaseConfig = "defconfig";
     kernelBaseConfig = "defconfig";
     # Build whatever possible as a module, if not stated in the extra config.
     kernelAutoModules = true;
     kernelTarget = "bzImage";
-    # Currently ignored - it should be set according to 'system' once it is
-    # not ignored. This is for stdenv-updates.
-    kernelArch = "i386";
     kernelExtraConfig =
       ''
         # Virtualisation (KVM, Xen...).
@@ -24,7 +21,15 @@ rec {
       '';
   };
 
-  pc_simplekernel = pc // {
+  pc64 = pcBase // { kernelArch = "x86_64"; };
+
+  pc32 = pcBase // { kernelArch = "i386"; };
+
+  pc32_simplekernel = pc32 // {
+    kernelAutoModules = false;
+  };
+
+  pc64_simplekernel = pc64 // {
     kernelAutoModules = false;
   };
 

pkgs/top-level/release-cross.nix

@@ -192,7 +192,7 @@ let
     arch = "i586";
     float = "hard";
     withTLS = true;
-    platform = pkgs.platforms.pc;
+    platform = pkgs.platforms.pc32;
     libc = "glibc";
     openssl.system = "hurd-x86";  # Nix depends on OpenSSL.
   };