[GHC] #13134: Simplifier ticks exhausted

[GHC]

#13134: Simplifier ticks exhausted
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           Reporter:  fumieval       |             Owner:
               Type:  task           |            Status:  new
           Priority:  low            |         Milestone:
          Component:  Compiler       |           Version:  8.0.2
           Keywords:                 |  Operating System:  Linux
       Architecture:  x86_64         |   Type of failure:  Compile-time
  (amd64)                            |  crash or panic
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 When compiling generics-rich code I got this panic. I had to increase
 `-fsimpl-tick-factor` to 110 to fix the problem.

 {{{
 <no location info>: error:
     ghc: panic! (the 'impossible' happened)
   (GHC version 8.0.2 for x86_64-unknown-linux):
         Simplifier ticks exhausted
   When trying UnfoldingDone f_s1dfn
   To increase the limit, use -fsimpl-tick-factor=N (default 100)
   If you need to do this, let GHC HQ know, and what factor you needed
   To see detailed counts use -ddump-simpl-stats
   Total ticks: 19189

 Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug
 }}}

 I attached the output of `-ddump-simpl-stats`.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13134>
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