Add NFData instances

src/Builder.hs

@@ -111,3 +111,4 @@ fixAbsolutePathOnWindows path = do
 -- Instances for storing in the Shake database
 instance Binary Builder
 instance Hashable Builder
+instance NFData Builder

src/Package.hs

@@ -49,3 +49,4 @@ instance Ord Package where
 instance Binary Package
 instance Hashable Package where
     hashWithSalt salt = hashWithSalt salt . show
+instance NFData Package

src/Stage.hs

@@ -13,3 +13,4 @@ instance Show Stage where
 -- Instances for storing in the Shake database
 instance Binary Stage
 instance Hashable Stage
+instance NFData Stage

src/Way.hs

@@ -169,3 +169,6 @@ instance Binary Way where
 
 instance Hashable Way where
     hashWithSalt salt = hashWithSalt salt . show
+
+instance NFData Way where
+    rnf (Way s) = s `seq` ()