[GHC] #8273: ghc: panic! (the 'impossible' happened)

[GHC]

#8273: ghc: panic! (the 'impossible' happened)
-------------------------+-------------------------------------------------
       Reporter:         |             Owner:
  ready2go               |            Status:  new
           Type:  bug    |         Milestone:
       Priority:         |           Version:  7.4.1
  normal                 |  Operating System:  Unknown/Multiple
      Component:         |   Type of failure:  None/Unknown
  Compiler               |         Test Case:  Prelude>  data Shape =
       Keywords:         |  Circle Float Float Float | Rectangle Float
   Architecture:         |  Float Float Float deriving (show)
  x86_64 (amd64)         |          Blocking:
     Difficulty:         |
  Unknown                |
     Blocked By:         |
Related Tickets:         |
-------------------------+-------------------------------------------------
 Prelude>  data Shape = Circle Float Float Float | Rectangle Float Float
 Float Float deriving (show)
 ghc: panic! (the 'impossible' happened)
   (GHC version 7.4.1 for x86_64-unknown-linux):
         nameModule show{tv a9J}

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

 My Apologies if this is a duplicate, first time I have used trac, or this
 system- reproduced fault twice from fresh start of GHCi it twice on my
 Ubuntu 12.04 LTS system, using Haskell platform from Ubuntu repository

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8273>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler