[GHC] #7965: The 'impossible' happened!

[GHC]

#7965: The 'impossible' happened!
-------------------------------+--------------------------------------------
Reporter:  adit                |          Owner:                
    Type:  bug                 |         Status:  new           
Priority:  normal              |      Component:  Compiler      
 Version:  7.4.1               |       Keywords:                
      Os:  MacOS X             |   Architecture:  x86_64 (amd64)
 Failure:  Compile-time crash  |      Blockedby:                
Blocking:                      |        Related:                
-------------------------------+--------------------------------------------

Comment(by adit):

 Ok, I was able to narrow it down to two lines:

     data Color = Red | Blue deriving (show)
     main = print Red

 see that `deriving (show)` with `show` lowercase? That's what's causing
 the bug. I haven't tried this with 7.6, so apologies if it was already
 fixed.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7965#comment:1>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler