[GHC] #13910: Inlining a definition causes GHC to panic (repSplitTyConApp_maybe)

[GHC]

#13910: Inlining a definition causes GHC to panic (repSplitTyConApp_maybe)
-------------------------------------+-------------------------------------
        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.2.1-rc2
  checker)                           |
      Resolution:                    |             Keywords:  TypeInType
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash or panic                     |            Test Case:
      Blocked By:  14119             |             Blocking:
 Related Tickets:  #13877, #14038    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by RyanGlScott):

 Humorously enough, the panic is now different on GHC HEAD (likely due to
 commit a6c448b403dbe8720178ca82100f34baedb1f47e, `Small refactor of
 getRuntimeRep`):

 {{{
 $ ghc4/inplace/bin/ghc-stage2 --interactive Bug.hs
 GHCi, version 8.3.20170828: http://www.haskell.org/ghc/  :? for help
 Loaded GHCi configuration from /home/rgscott/.ghci
 [1 of 1] Compiling Bug              ( Bug.hs, interpreted )
 ghc-stage2: panic! (the 'impossible' happened)
   (GHC version 8.3.20170828 for x86_64-unknown-linux):
         getRuntimeRep
   (f_a5yC[sk:2] |> Sym (Sym (D:R:Funk1:->k2[0]
                                  <k1_a5n2>_N <k2_a5n3>_N) ;
 D:R:Funk1:->k2[0]
 <t1_a5yB[sk:2]>_N
                                                                 <*>_N))
 a_a5yD[sk:2] :: k2_a5n3
   Call stack:
       CallStack (from HasCallStack):
         callStackDoc, called at compiler/utils/Outputable.hs:1138:37 in
 ghc:Outputable
         pprPanic, called at compiler/types/Type.hs:1982:18 in ghc:Type
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13910#comment:3>
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