[GHC] #10754: truncate /= double2Int

[GHC]

#10754: truncate /= double2Int
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        Reporter:  cblp              |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  libraries/base    |                 Version:  7.10.2
      Resolution:                    |                Keywords:  truncate,
                                     |  double2Int, rewrite, rule
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  Incorrect result  |  Unknown/Multiple
  at runtime                         |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by cblp):

 Infinity is not representable in Int. Maybe maxBound is the closest
 answer, and they both must return maxBound, maybe they both must throw an
 exception. I don't know the precise answer.

 But I know they must return the same value, or it must be documented as
 undefined behaviour. Currently this rule is invalid.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10754#comment:2>
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