[GHC] #15428: Oversaturated type family application panicks GHC (piResultTys2)

[GHC]

#15428: Oversaturated type family application panicks GHC (piResultTys2)
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        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.5
      Resolution:                    |             Keywords:  TypeInType,
                                     |  TypeFamilies
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"e1b5a1174e42e390855b153015ce5227b3251d89/ghc" e1b5a11/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="e1b5a1174e42e390855b153015ce5227b3251d89"
 Fix a nasty bug in piResultTys

 I was failing to instantiate vigorously enough in Type.piResultTys
 and in the very similar function ToIface.toIfaceAppArgsX

 This caused Trac #15428.  The fix is easy.

 See Note [Care with kind instantiation] in Type.hs
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15428#comment:4>
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