[GHC] #9125: int-to-float conversion broken on ARM - 7.8.1-rc2

[GHC]

#9125: int-to-float conversion broken on ARM - 7.8.1-rc2
--------------------------+------------------------------------------------
       Reporter:          |             Owner:
  Ansible                 |            Status:  new
           Type:  bug     |         Milestone:
       Priority:  normal  |           Version:  7.8.1
      Component:          |  Operating System:  Linux
  Compiler                |   Type of failure:  Incorrect result at runtime
       Keywords:          |         Test Case:
   Architecture:  arm     |          Blocking:
     Difficulty:          |
  Unknown                 |
     Blocked By:          |
Related Tickets:          |
--------------------------+------------------------------------------------
 I compiled ghc on the raspberry pi.  See this bug for more about that
 build of ghc: [https://ghc.haskell.org/trac/ghc/ticket/8896 8896].

 A simple test program:


 {{{
 main = do
   mapM_ (print . (fromInteger :: Integer -> Float)) [0..100]

 }}}

 And the result:


 {{{
 0.0
 127.0
 256.0
 257.0
 516.0
 517.0
 518.0
 519.0
 1040.0
 1041.0
 1042.0
 1043.0
 1044.0
 1045.0
 1046.0
 1047.0
 2096.0
 2097.0
 2098.0
 2099.0
 2100.0
 2101.0
 2102.0
 2103.0
 2104.0
 2105.0
 2106.0
 2107.0
 2108.0
 2109.0
 2110.0
 2111.0
 4224.0
 4225.0
 4226.0
 4227.0
 4228.0
 4229.0
 4230.0
 4231.0
 4232.0
 4233.0
 4234.0
 4235.0
 4236.0
 4237.0
 4238.0
 4239.0
 4240.0
 4241.0
 4242.0
 4243.0
 4244.0
 4245.0
 4246.0
 4247.0
 4248.0
 4249.0
 4250.0
 4251.0
 4252.0
 4253.0
 4254.0
 4255.0
 8512.0
 8513.0
 8514.0
 8515.0
 8516.0
 8517.0
 8518.0
 8519.0
 8520.0
 8521.0
 8522.0
 8523.0
 8524.0
 8525.0
 8526.0
 8527.0
 8528.0
 8529.0
 8530.0
 8531.0
 8532.0
 8533.0
 8534.0
 8535.0
 8536.0
 8537.0
 8538.0
 8539.0
 8540.0
 8541.0
 8542.0
 8543.0
 8544.0
 8545.0
 8546.0
 8547.0
 8548.0
 8538.0

 }}}

 This code, however, works normally:


 {{{
 main = do
   mapM_ (print . (fromInteger :: Integer -> Double)) [0..100]
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9125>
GHC <http://www.haskell.org/ghc/>
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