diff --git a/pkgs/development/haskell-modules/configuration-ghc-7.6.x.nix b/pkgs/development/haskell-modules/configuration-ghc-7.6.x.nix
index d853e9265ba..5285484d2ff 100644
--- a/pkgs/development/haskell-modules/configuration-ghc-7.6.x.nix
+++ b/pkgs/development/haskell-modules/configuration-ghc-7.6.x.nix
@@ -70,4 +70,7 @@ self: super: {
   contravariant = addBuildDepend super.contravariant self.tagged;
   reflection = dontHaddock (addBuildDepend super.reflection self.tagged);
 
+  # The compat library is empty in the presence of mtl 2.2.x.
+  mtl-compat = dontHaddock super.mtl-compat;
+
 }