[GHC] #8954: Reifying the nullary unboxed tuple is broken

[GHC]

#8954: Reifying the nullary unboxed tuple is broken
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       Reporter:  goldfire          |             Owner:
           Type:  bug               |            Status:  new
       Priority:  low               |         Milestone:
      Component:  Template Haskell  |           Version:  7.8.1-rc2
       Keywords:                    |  Operating System:  Unknown/Multiple
   Architecture:  Unknown/Multiple  |   Type of failure:  None/Unknown
     Difficulty:  Unknown           |         Test Case:
     Blocked By:                    |          Blocking:
Related Tickets:                    |
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 Here is my code:
 {{{
 {-# LANGUAGE TemplateHaskell, UnboxedTuples #-}

 module Bug where

 import Language.Haskell.TH

 $( do _ <- reify ''(##)
       return [] )
 }}}

 And here is GHC's response:
 {{{
     Can't find interface-file declaration for type constructor or class
 GHC.Prim.(##)
       Probable cause: bug in .hi-boot file, or inconsistent .hi file
       Use -ddump-if-trace to get an idea of which file caused the error
 }}}

 Non-nullary unboxed tuples behave fine. This behavior is the same whether
 or not there is a space in the nullary unboxed tuple.

 Believe me -- I actually was just bit by this bug. I'm happy to fix, but
 could someone give me a pointer as to where the problem might be? I have
 the feeling someone reading this will know quite quickly.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8954>
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