[GHC] #12850: Panic with unboxed integers and ghci

[GHC]

#12850: Panic with unboxed integers and ghci
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           Reporter:  monoidal       |             Owner:
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.0.1
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  GHCi crash
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 Attempting to load the following file in ghci causes a panic in
 getIdFromTrivialExpr. Tested in GHC 8.0.1 and HEAD.

 {{{
 {-# LANGUAGE ExplicitForAll, MagicHash, KindSignatures #-}
 import GHC.Types (RuntimeRep(..), TYPE)

 f :: forall (x :: TYPE 'IntRep). x -> x
 f x = x

 g = ()
     where h = f 0#
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12850>
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