[GHC] #15670: FloatFnInverses seems to show some weird rounding/precision issues.

[GHC]

#15670: FloatFnInverses seems to show some weird rounding/precision issues.
----------------------------------------+---------------------------------
           Reporter:  Phyx-             |             Owner:  (none)
               Type:  bug               |            Status:  new
           Priority:  normal            |         Milestone:  8.6.1
          Component:  Compiler          |           Version:  8.4.3
           Keywords:                    |  Operating System:  Windows
       Architecture:  Unknown/Multiple  |   Type of failure:  None/Unknown
          Test Case:                    |        Blocked By:
           Blocking:                    |   Related Tickets:
Differential Rev(s):                    |         Wiki Page:
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 There seems to be a rounding issue with math functions on Windows.  We
 likely need a crt update to fix this. Or maybe check the round mode if
 it's being set correctly.

 {{{
 ---
 numeric/should_run/FloatFnInverses.run/FloatFnInverses.stdout.normalised
 2018-09-23 17:26:01.581150200 +0100
 +++
 numeric/should_run/FloatFnInverses.run/FloatFnInverses.run.stdout.normalised
 2018-09-23 17:26:01.583146400 +0100
 @@ -8,8 +8,8 @@
 [0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0]
  [0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0]
  [0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0]
 -[0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0]
 -[0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0]
 +[Infinity,Infinity,Infinity,Infinity,Infinity,Infinity,Infinity,Infinity,Infinity,Infinity,Infinity,Infinity,Infinity,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,-Infinity,-Infinity,-Infinity,-Infinity,-Infinity,-Infinity,-Infinity,-Infinity,-Infinity,-Infinity,-Infinity,-Infinity,-Infinity]
 +[7.788445287802241e33,7.788445287802241e33,7.788445287802241e33,7.788445287802241e33,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,-7.788445287802241e33,-7.788445287802241e33,-7.788445287802241e33,-7.788445287802241e33,-7.788445287802241e33]
 [0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0]
  [0.0,0.0,0.0,0.0,0.0,0.0]
  [0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0]
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15670>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler