[GHC] #11670: Can't infer type

[GHC]

#11670: Can't infer type
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        Reporter:  Iceland_jack      |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.10.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Iceland_jack):

 This also fails:

 {{{#!hs
 peek :: Ptr CTimeval -> IO CTimeval
 peek ptr = do
   s :: CLong <- peekElemOff (castPtr ptr) 0 :: IO _
   mus        <- peekElemOff (castPtr ptr) 1
   return (MkCTimeval (s :: CLong) mus)
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11670#comment:1>
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