1 files changed, 29 insertions, 0 deletions
diff --git a/testsuite/tests/codeGen/should_run/3207.hs b/testsuite/tests/codeGen/should_run/3207.hs
new file mode 100644
index 0000000000..4738fca343
--- /dev/null
+++ b/testsuite/tests/codeGen/should_run/3207.hs
@@ -0,0 +1,29 @@
+module Main where
+
+import Control.Monad.ST.Lazy
+import Data.STRef.Lazy
+import Data.Array.ST
+import Data.Int
+import Debug.Trace
+
+data Refs s = Refs
+    { memory    :: STArray s Int8 Int8
+    , pc        :: STRef s Int8
+    }
+
+main :: IO ()
+main = do
+    print $ runST m
+  where
+    m = do
+      m <- newArray_ (0,30)
+      p <- newSTRef 0
+      let r = Refs m p
+      writeArray m 0 0x4
+      v <- readSTRef p
+      modifySTRef p (+1)
+--      trace ("v: " ++ show v) $ return ()
+      op <- readArray m v
+      case {- trace ("v: " ++ show v) $ -} op of
+          0x4 -> modifySTRef p (+100) -- should run this
+          n   -> error ("should never match this: " ++ show n)