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break003 fails with a DEBUG compiler:

$ cat Test3.hs
mymap f [] = []
mymap f (x:xs) = f x:mymap f xs

main = mapM_ putStrLn $ mymap ('a':) ["hello","bye"] 

$ ghci Test3.hs 
GHCi, version 7.4.0.20120126: http://www.haskell.org/ghc/  :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
[1 of 1] Compiling Main             ( Test3.hs, interpreted )
Ok, modules loaded: Main.
*Main> :b 2
Breakpoint 0 activated at Test3.hs:2:18-31
*Main> main
Stopped at Test3.hs:2:18-31
_result :: [a] = _
f :: t -> a = _
x :: t = _
xs :: [t] = [_]
[Test3.hs:2:18-31] *Main> f
ghc-stage2: panic! (the 'impossible' happened)
  (GHC version 7.4.0.20120126 for x86_64-apple-darwin):
        ASSERT failed! file compiler/typecheck/TcEnv.lhs line 427
( it{v am5} [lid] :: ( t{tv Im0} [rt] :: ghc-prim:GHC.Prim.*{(w) tc 34d} )
                     -> ( a{tv Im1} [rt] :: ghc-prim:GHC.Prim.*{(w) tc 34d} ) )
( t{tv Im0} [rt] :: ghc-prim:GHC.Prim.*{(w) tc 34d} )
-> ( a{tv Im1} [rt] :: ghc-prim:GHC.Prim.*{(w) tc 34d} )

Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

[Test3.hs:2:18-31] *Main>

break006 and print019 fail similarly.