[GHC] #14080: GHC panic while forcing the thunk for TyThing IsFile (regression)

[GHC]

#14080: GHC panic while forcing the thunk for TyThing IsFile (regression)
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        Reporter:  inaki             |                Owner:  (none)
            Type:  bug               |               Status:  infoneeded
        Priority:  high              |            Milestone:  8.2.2
       Component:  Compiler          |              Version:  8.2.1
      Resolution:                    |             Keywords:  hs-boot
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #13803, #13981    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by inaki):

 That seems to be indeed the case. I cherry picked this commit (together
 with some related ones, as detailed in [ticket:13719#comment:8]) into the
 `8.2` branch. This got rid of the issue reported here, but the original
 issue in #13803, `ghc` panicking when building `gi-gio`, is still there...

 Sigh. Now I am not sure how to proceed. I can try to reduce the panic with
 the patches above applied to the `8.2` branch, and file yet another issue.
 Would that be the best way to proceed? Or should I reopen the original
 #13803?

 In either case the whole process of reducing and bisecting is extremely
 time consuming, I would really appreciate some guidance (even if it is
 just a guess).

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14080#comment:9>
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