[GHC] #7827: GHC internal error: `a' is not in scope during type checking, but it passed the renamer

[GHC]

#7827: GHC internal error: `a' is not in scope during type checking, but it passed
the renamer
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Reporter:  guest                      |          Owner:                  
    Type:  bug                        |         Status:  new             
Priority:  normal                     |      Component:  Compiler        
 Version:  7.6.2                      |       Keywords:                  
      Os:  Unknown/Multiple           |   Architecture:  Unknown/Multiple
 Failure:  GHC rejects valid program  |      Blockedby:                  
Blocking:                             |        Related:                  
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Comment(by monoidal):

 Here's a smaller version.

 {{{
 {-# LANGUAGE ScopedTypeVariables #-}
 module Main where

 bug :: a -> Int
 bug ((x :: a) :: a) = undefined
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7827#comment:3>
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