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diff --git a/testsuite/tests/typecheck/should_run/tcrun040.hs b/testsuite/tests/typecheck/should_run/tcrun040.hs
new file mode 100644
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+++ b/testsuite/tests/typecheck/should_run/tcrun040.hs
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+-- Sven Panne found this example; a mistake in typechecking 
+-- lazy patterns made functions too strict in a version of
+-- GHC 6.7
+
+module Main where
+
+import Foreign
+
+-- Strangely enough, this works if newtype is used...
+data Elem a = Elem a
+
+instance Storable a => Storable (Elem a) where
+   sizeOf ~(Elem r) = 3 * sizeOf r
+   alignment ~(Elem r) = alignment r
+   peek ptr = do r <- peekElemOff (castPtr ptr) 0; return (Elem r)
+   poke ptr (Elem r) = poke (castPtr ptr) r
+
+main :: IO ()
+main = do
+   putStrLn "*** main 1"
+   allocaBytes 100 $ \buf -> do
+      poke buf (Elem 12345)
+      putStrLn "*** main 2"
+      Elem x <- peekElemOff buf 0
+      print (x :: Int)
+      putStrLn "*** main 3"
+