[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):

 I just checked on HEAD, and the panic is not there anymore (with or
 without the fix to #14075). For the tip of the `8.2` branch, the panic is
 there with or without the fix to #14075.

 Interestingly, the panic when building `gi-gio` originally reported in
 #13803 is gone in HEAD if I include the fix to #14075 (otherwise it is
 still present). This is great!

 So I wonder if it is possible to backport to the `8.2` branch whatever
 fixed this in HEAD? Or alternatively, can you see any way of working
 around the panic reported above with `8.2`?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14080#comment:3>
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