[GHC] #13071: GHCi 8.0.1 panic with PatternSynonyms

[GHC]

#13071: GHCi 8.0.1 panic with PatternSynonyms
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        Reporter:  taktoa      |                Owner:
            Type:  bug         |               Status:  new
        Priority:  normal      |            Milestone:
       Component:  GHCi        |              Version:  8.0.1
      Resolution:              |             Keywords:  PatternSynonyms
Operating System:  Linux       |         Architecture:  Unknown/Multiple
 Type of failure:  GHCi crash  |            Test Case:
      Blocked By:              |             Blocking:
 Related Tickets:              |  Differential Rev(s):
       Wiki Page:              |
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Comment (by cactus):

 We can simplify the code even further, and still have it crash GHCi:


 {{{
 {-# LANGUAGE PatternSynonyms #-}

 data D1 = MkD1
 data D2 = MkD2 D1

 pattern P1 = MkD1
 pattern P2 = MkD2 P1

 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13071#comment:1>
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