[GHC] #7174: panic when using function in 'deriving' data declaration

[GHC]

#7174: panic when using function in 'deriving' data declaration
--------------------------------+-------------------------------------------
 Reporter:  shapeshifter        |          Owner:                  
     Type:  bug                 |         Status:  new             
 Priority:  normal              |      Component:  Compiler        
  Version:  7.4.2               |       Keywords:                  
       Os:  Linux               |   Architecture:  Unknown/Multiple
  Failure:  Compile-time crash  |       Testcase:                  
Blockedby:                      |       Blocking:                  
  Related:                      |  
--------------------------------+-------------------------------------------
 Hello. I haven't found any matching bugs for this. To reproduce:

 1) Start up ghci

 2) Enter something like the following, which contains a typo 'show'
 instead of 'Show'.

 {{{
 data Test = Yes | No deriving (show, Eq)
 }}}



 3) ghci will panic saying:

 {{{
 Prelude> data Test = Yes | No deriving (show, Eq)
 ghc: panic! (the 'impossible' happened)
   (GHC version 7.4.2 for i386-unknown-linux):
         nameModule show{tv aa0}
 }}}

 Notes:


  * The 'show' can be substituted with any other function name
  * It also happens on x86_64.
  * It also happens when putting such a line into a .hs file and trying to
 compile it

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7174>
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