[GHC] #8743: The impossible happened : Prelude.(!!): index too large

[GHC]

#8743: The impossible happened : Prelude.(!!): index too large
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        Reporter:  erikd               |            Owner:  nomeata
            Type:  bug                 |           Status:  new
        Priority:  highest             |        Milestone:  7.8.1
       Component:  Compiler            |          Version:  7.8.1-rc1
      Resolution:                      |         Keywords:
Operating System:  Unknown/Multiple    |     Architecture:  x86_64 (amd64)
 Type of failure:  Compile-time crash  |       Difficulty:  Unknown
       Test Case:                      |       Blocked By:
        Blocking:                      |  Related Tickets:
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Changes (by nomeata):

 * owner:   => nomeata


Comment:

 Thanks for the debugging, that is very helpful. It is likely a problem
 caused by the demand analyser ignoring coercions, so sometimes the type do
 not match up; in that the solution will be to just make the code more
 forgiving.

 Will look into it later today.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8743#comment:5>
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