#9810: encodeFloat 1 2047 = -1024.0 -------------------------------------+------------------------------------- Reporter: luite | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.9 Keywords: | Operating System: Architecture: Unknown/Multiple | Unknown/Multiple Difficulty: Unknown | Type of failure: Blocked By: | None/Unknown Related Tickets: | Test Case: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- When the following code is compiled with optimization, it prints `-1024.0`, without optimization the result is `Infinity`. {{{#!hs main = print ((encodeFloat 1 2047) :: Double) }}} I think this might be caused by changes in decoding doubles in `integer- gmp2`. While `decodeFloat` is lossy, since we can not represent exceptional values, `encodeFloat` should never give a different answer here. Also `cgrun044` now gives a different result when compiled with optimization. It was broken anyway, since it claims some values are `NaN`, while actually `Infinity` is printed (also with 7.8), but it used to give the same answer regardless of optimization with GHC 7.8 -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9810 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler