So, it appears that the one ending with 21 is the likely correct result; as opposed to 22. Is this an issue with some underlying library (glibc etc.); or an issue with GHC itself? On Sat, Jul 12, 2014 at 8:03 PM, GHC wrote:

#9304: Floating point woes; Different behavior on Mac vs Linux -------------------------------------+------------------------------------ Reporter: lerkok | Owner: Type: bug | Status: new Priority: high | Milestone: Component: Compiler | Version: 7.8.3 Resolution: | Keywords: floating point Operating System: Unknown/Multiple | Architecture: Unknown/Multiple Type of failure: None/Unknown | Difficulty: Unknown Test Case: | Blocked By: 9276 Blocking: | Related Tickets: -------------------------------------+------------------------------------

Comment (by carter):

I ran it on a 64 bit linux server i have using ghci {{{ Prelude> :set -XScopedTypeVariables Prelude> let x :: Double = -4.4 Prelude> let y :: Double = 2.4999999999999956 Prelude> decodeFloat (x*y) (-6192449487634421,-49)

}}}

so if anything, it looks like its 32bit vs 64bit

could you try running the above snippet in GHCi on your 32bit machine?

-- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9304#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler