[GHC] #10515: ghc: panic: tyThingTyCon Identifier ‘$fStencil:.a(,,,,)7’

[GHC]

#10515: ghc: panic: tyThingTyCon Identifier ‘$fStencil:.a(,,,,)7’
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              Reporter:  yongqli     |             Owner:
                  Type:  bug         |            Status:  new
              Priority:  normal      |         Milestone:
             Component:  Compiler    |           Version:  7.10.1
              Keywords:              |  Operating System:  Unknown/Multiple
          Architecture:              |   Type of failure:  None/Unknown
  Unknown/Multiple                   |        Blocked By:
             Test Case:              |   Related Tickets:
              Blocking:              |
Differential Revisions:              |
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 Has anyone seen something like this?

 {{{
 <no location info>:
     ghc: panic! (the 'impossible' happened)
   (GHC version 7.10.1.20150519 for x86_64-unknown-linux):
         tyThingTyCon Identifier ‘$fStencil:.a(,,,,)7’
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10515>
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