[GHC] #13803: Panic while forcing the thunk for TyThing IsFile (regression)

[GHC]

#13803: Panic while forcing the thunk for TyThing IsFile (regression)
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        Reporter:  inaki             |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.1-rc2
      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:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 It also means that less work is done (and perhaps even fewer interface
 files read, which is big) if the axiom is never actually needed.  So it
 might be ''more'' efficient.   Not reading interface files too eagerly is
 one of the original reasons for the whole `forkM` story in `TcIface`.

 Would you like to try?

 Please comment the change, with a reference to this ticket.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13803#comment:13>
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