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GADT syntax for newtype causes tcConDecl exception

$ cat Bug.hs
{-# OPTIONS -fglasgow-exts #-}
module Bug where
newtype Bug a where Bug :: a -> Bug a

$ ghc -c Bug.hs
ghc-6.6: panic! (the 'impossible' happened)
  (GHC version 6.6 for i386-unknown-linux):
        typecheck/TcTyClsDecls.lhs:(468,0)-(524,4): Non-exhaustive patterns in function tcConDecl


Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug
Trac metadata
Trac field Value
Version 6.6
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture Unknown
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