* Export the original input attributes of the derivation in

‘drvAttrs’.  This will simplify the implementation of functions such
  as ‘overrideDerivation’ in Nixpkgs, which need to filter out any
  added attributes such as outPath.

corepkgs/derivation.nix

@@ -7,7 +7,10 @@ let
 
   strict = derivationStrict drvAttrs;
   
-  commonAttrs = drvAttrs // (builtins.listToAttrs outputsList) // { all = map (x: x.value) outputsList; };
+  commonAttrs = drvAttrs // (builtins.listToAttrs outputsList) //
+    { all = map (x: x.value) outputsList;
+      inherit drvAttrs;
+    };
 
   outputToAttrListElement = outputName:
     { name = outputName;