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diff --git a/third_party/bazel/rules_haskell/examples/primitive/Data/Primitive/Ptr.hs b/third_party/bazel/rules_haskell/examples/primitive/Data/Primitive/Ptr.hs
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+{-# LANGUAGE CPP #-}
+{-# LANGUAGE MagicHash #-}
+{-# LANGUAGE UnboxedTuples #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+
+-- |
+-- Module      : Data.Primitive.Ptr
+-- Copyright   : (c) Roman Leshchinskiy 2009-2012
+-- License     : BSD-style
+--
+-- Maintainer  : Roman Leshchinskiy <rl@cse.unsw.edu.au>
+-- Portability : non-portable
+--
+-- Primitive operations on machine addresses
+--
+-- @since 0.6.4.0
+
+module Data.Primitive.Ptr (
+  -- * Types
+  Ptr(..),
+
+  -- * Address arithmetic
+  nullPtr, advancePtr, subtractPtr,
+
+  -- * Element access
+  indexOffPtr, readOffPtr, writeOffPtr,
+
+  -- * Block operations
+  copyPtr, movePtr, setPtr
+
+#if __GLASGOW_HASKELL__ >= 708
+  , copyPtrToMutablePrimArray
+#endif
+) where
+
+import Control.Monad.Primitive
+import Data.Primitive.Types
+#if __GLASGOW_HASKELL__ >= 708
+import Data.Primitive.PrimArray (MutablePrimArray(..))
+#endif
+
+import GHC.Base ( Int(..) )
+import GHC.Prim
+
+import GHC.Ptr
+import Foreign.Marshal.Utils
+
+
+-- | Offset a pointer by the given number of elements.
+advancePtr :: forall a. Prim a => Ptr a -> Int -> Ptr a
+{-# INLINE advancePtr #-}
+advancePtr (Ptr a#) (I# i#) = Ptr (plusAddr# a# (i# *# sizeOf# (undefined :: a)))
+
+-- | Subtract a pointer from another pointer. The result represents
+--   the number of elements of type @a@ that fit in the contiguous
+--   memory range bounded by these two pointers.
+subtractPtr :: forall a. Prim a => Ptr a -> Ptr a -> Int
+{-# INLINE subtractPtr #-}
+subtractPtr (Ptr a#) (Ptr b#) = I# (quotInt# (minusAddr# a# b#) (sizeOf# (undefined :: a)))
+
+-- | Read a value from a memory position given by a pointer and an offset.
+-- The memory block the address refers to must be immutable. The offset is in
+-- elements of type @a@ rather than in bytes.
+indexOffPtr :: Prim a => Ptr a -> Int -> a
+{-# INLINE indexOffPtr #-}
+indexOffPtr (Ptr addr#) (I# i#) = indexOffAddr# addr# i#
+
+-- | Read a value from a memory position given by an address and an offset.
+-- The offset is in elements of type @a@ rather than in bytes.
+readOffPtr :: (Prim a, PrimMonad m) => Ptr a -> Int -> m a
+{-# INLINE readOffPtr #-}
+readOffPtr (Ptr addr#) (I# i#) = primitive (readOffAddr# addr# i#)
+
+-- | Write a value to a memory position given by an address and an offset.
+-- The offset is in elements of type @a@ rather than in bytes.
+writeOffPtr :: (Prim a, PrimMonad m) => Ptr a -> Int -> a -> m ()
+{-# INLINE writeOffPtr #-}
+writeOffPtr (Ptr addr#) (I# i#) x = primitive_ (writeOffAddr# addr# i# x)
+
+-- | Copy the given number of elements from the second 'Ptr' to the first. The
+-- areas may not overlap.
+copyPtr :: forall m a. (PrimMonad m, Prim a)
+  => Ptr a -- ^ destination pointer
+  -> Ptr a -- ^ source pointer
+  -> Int -- ^ number of elements
+  -> m ()
+{-# INLINE copyPtr #-}
+copyPtr (Ptr dst#) (Ptr src#) n
+  = unsafePrimToPrim $ copyBytes (Ptr dst#) (Ptr src#) (n * sizeOf (undefined :: a))
+
+-- | Copy the given number of elements from the second 'Ptr' to the first. The
+-- areas may overlap.
+movePtr :: forall m a. (PrimMonad m, Prim a)
+  => Ptr a -- ^ destination address
+  -> Ptr a -- ^ source address
+  -> Int -- ^ number of elements
+  -> m ()
+{-# INLINE movePtr #-}
+movePtr (Ptr dst#) (Ptr src#) n
+  = unsafePrimToPrim $ moveBytes (Ptr dst#) (Ptr src#) (n * sizeOf (undefined :: a))
+
+-- | Fill a memory block with the given value. The length is in
+-- elements of type @a@ rather than in bytes.
+setPtr :: (Prim a, PrimMonad m) => Ptr a -> Int -> a -> m ()
+{-# INLINE setPtr #-}
+setPtr (Ptr addr#) (I# n#) x = primitive_ (setOffAddr# addr# 0# n# x)
+
+
+#if __GLASGOW_HASKELL__ >= 708
+-- | Copy from a pointer to a mutable primitive array.
+-- The offset and length are given in elements of type @a@.
+-- This function is only available when building with GHC 7.8
+-- or newer.
+copyPtrToMutablePrimArray :: forall m a. (PrimMonad m, Prim a)
+  => MutablePrimArray (PrimState m) a -- ^ destination array
+  -> Int -- ^ destination offset
+  -> Ptr a -- ^ source pointer
+  -> Int -- ^ number of elements
+  -> m ()
+{-# INLINE copyPtrToMutablePrimArray #-}
+copyPtrToMutablePrimArray (MutablePrimArray ba#) (I# doff#) (Ptr addr#) (I# n#) = 
+  primitive_ (copyAddrToByteArray# addr# ba# (doff# *# siz#) (n# *# siz#))
+  where
+  siz# = sizeOf# (undefined :: a)
+#endif