[GHC] #15646: ghci takes super long time to find the type of large fractional number

[GHC]

#15646: ghci takes super long time to find the type of large fractional number
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        Reporter:  Johannkokos       |                Owner:
                                     |  JulianLeviston
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  GHCi              |              Version:  8.4.3
      Resolution:                    |             Keywords:  newcomer
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #5692             |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by JulianLeviston):

 As discussed on IRC, I encountered an issue where moving the code into
 `GHC.Real` doesn't help because Stage 1 is not using *that* `GHC.Real`,
 it's using the module from the GHC being used to compile the target GHC
 rather than the target GHC itself.

 So, what I'm going to do is spend a little bit of time to summarize my
 understanding of exactly what my attempt is currently and how to
 understand the code I've written so that we're all on the same page and
 others can help me more easily. Stay tuned :)

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15646#comment:65>
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