diff --git a/pkgs/lib/misc.nix b/pkgs/lib/misc.nix
index 85fa1629b0b6..91a374947446 100644
--- a/pkgs/lib/misc.nix
+++ b/pkgs/lib/misc.nix
@@ -392,4 +392,16 @@ rec {
           (eqListStrict (attrNames a) (attrNames b))
           && (eqListStrict (lib.attrValues a) (lib.attrValues b))
         else a == b; # FIXME !
+
+
+  # Check absence of non-used options
+  # Obsolete?
+  checker = x: flag: opts: config:
+    (if flag then let result=(
+      (import ../build-support/checker)
+      opts config); in
+      (if (result=="") then x else
+      abort ("Unknown option specified: " + result))
+    else x);
+
 }
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 339278300e8a..39a2016636f8 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -149,15 +149,6 @@ let
   # Return the first available value in the order: pkg.val, val, or default.
   getPkgConfig = pkg : val : default : (getConfig [ pkg val ] (getConfig [ val ] default));
 
-  # Check absence of non-used options
-  checker = x: flag: opts: config:
-    (if flag then let result=(
-      (import ../build-support/checker)
-      opts config); in
-      (if (result=="") then x else
-      abort ("Unknown option specified: " + result))
-    else x);
-
   builderDefs = lib.composedArgsAndFun (import ../build-support/builder-defs/builder-defs.nix) {
     inherit stringsWithDeps lib stdenv writeScript
       fetchurl fetchmtn fetchgit;