[GHC] #7455: ghc panic on show

[GHC]

#7455: ghc panic on show
-------------------------------+--------------------------------------------
Reporter:  fegu                |          Owner:                 
    Type:  bug                 |         Status:  new            
Priority:  normal              |      Component:  Compiler       
 Version:  7.4.1               |       Keywords:  panic show Show
      Os:  Windows             |   Architecture:  x86            
 Failure:  Compile-time crash  |      Blockedby:                 
Blocking:                      |        Related:                 
-------------------------------+--------------------------------------------
 --- ghccrash.hs
 main = do
   putStrLn "Minimal compiler bug example"

 data VariationInfo = Variation{
   somefield :: Bool
   } deriving (show) -- set small s in show to crash ghc 7.4.1

 --- OUTPUT:
 D:\Prosjekt.FE\Haskell>ghc ghccrash.hs
 [1 of 1] Compiling Main             ( ghccrash.hs, ghccrash.o )
 ghc: panic! (the 'impossible' happened)
   (GHC version 7.4.1 for i386-unknown-mingw32):
         nameModule show{tv a9M}

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

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7455>
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