anchor.diff:      xset = linux;
     };
   
  -} ))
  +} )) // (
  +/* Test some cross builds to the Sheevaplug */
  +let
  +  crossSystem = {
  +      config = "armv5tel-unknown-linux-gnueabi";  
  +      bigEndian = false;
  +      arch = "arm";
  +      float = "soft";
  +  };
  +  nativePlatforms = linux;
  +in {
  +  crossArmLinux = mapTestOnCross crossSystem (rec {
  +    bison = nativePlatforms;
  +    uboot = nativePlatforms;
  +    uclibc = nativePlatforms;
  +    xorg = {
  +      fontadobe100dpi = nativePlatforms;
  +      fontadobe75dpi = nativePlatforms;
  +      fontbh100dpi = nativePlatforms;
  +      fontbhlucidatypewriter100dpi = nativePlatforms;
  +      fontbhlucidatypewriter75dpi = nativePlatforms;
  +      fontbhttf = nativePlatforms;
  +      fontcursormisc = nativePlatforms;
  +      fontmiscmisc = nativePlatforms;
  +      iceauth = nativePlatforms;
  +      libX11 = nativePlatforms;
  +      lndir = all;
  +      setxkbmap = nativePlatforms;
  +      xauth = nativePlatforms;
  +      xev = nativePlatforms;
  +      xf86inputkeyboard = nativePlatforms;
  +      xf86inputmouse = nativePlatforms;
  +      xf86inputevdev = nativePlatforms;
  +      xf86inputsynaptics = nativePlatforms;
  +      xf86videoati = nativePlatforms;
  +      xf86videointel = nativePlatforms;
  +      xf86videonv = nativePlatforms;
  +      xf86videovesa = nativePlatforms;
  +      xfs = nativePlatforms;
  +      xkbcomp = nativePlatforms;
  +      xmessage = nativePlatforms;
  +      xorgserver = nativePlatforms;
  +      xrandr = nativePlatforms;
  +      xrdb = nativePlatforms;
  +      xset = nativePlatforms;
  +    };
  +  gtkLibs = {
  +    gtk = nativePlatforms;
  +  };
  +  });
  +})
  
positive.code:      for the platform in question. */
    testOn = systems: f: {system ? builtins.currentSystem}:
      if pkgs.lib.elem system systems then f (allPackages {inherit system;}) else {};
  
    /* Map an attribute of the form `foo = [platforms...]'  to `testOn
       [platforms...] (pkgs: pkgs.foo)'. */
  
negative.code:           pkgs.lib.addMetaAttrs { schedulingPriority = toString job.schedulingPriority; }
            (pkgs.lib.getAttrFromPath path pkgs);
        in testOn job.systems getPkg);
  
  
    /* Similar to the testOn function, but with an additional 'crossSystem'
     * parameter for allPackages, defining the target platform for cross builds,
     * and triggering the build of the host derivation (cross built - hostDrv). */
    mapTestOnCross = crossSystem: pkgs.lib.mapAttrsRecursiveCond
      (as: !(as ? type && as.type == "job"))
      (path: value:
        let
          job = toJob value;
          getPkg = pkgs: setCrossMaintainers
            (pkgs.lib.addMetaAttrs { schedulingPriority = toString job.schedulingPriority; }
            (pkgs.lib.getAttrFromPath (path ++ ["hostDrv"]) pkgs));
        in testOnCross crossSystem job.systems getPkg);
  
    setCrossMaintainers = pkg: pkg // { meta.maintainers = crossMaintainers; };
  
    /* Find all packages that have a meta.platforms field listing the
       supported platforms. */
  