[GHC] #15577: TypeApplications-related infinite loop (GHC 8.6+ only)

[GHC]

#15577: TypeApplications-related infinite loop (GHC 8.6+ only)
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        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.6.1
       Component:  Compiler (Type    |              Version:  8.5
  checker)                           |             Keywords:
      Resolution:                    |  TypeApplications, TypeInType
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 OK, I've committed a fix -- worth merging.

 BUT '''please leave the ticket open'''.  Richard, Ningning: could you
 possibly look at whether there's a simple change to `flatten_args` that
 would eliminate these giant coercions ''in the case where there is
 literally no flattening to be done?''.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15577#comment:5>
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