#7858: Fix definitions of abs/signum for Floats/Doubles -------------------------------------+------------------------------------- Reporter: lerkok | Owner: bernalex Type: bug | Status: patch Priority: normal | Milestone: 7.10.1 Component: | Version: 7.6.3 libraries/base | Keywords: floating point Resolution: | Architecture: Unknown/Multiple Operating System: | Difficulty: Unknown Unknown/Multiple | Blocked By: Type of failure: | Related Tickets: #9238 None/Unknown | Test Case: | Blocking: | Differential Revisions: Phab:D145 | -------------------------------------+------------------------------------- Comment (by Austin Seipp <austin@…>): In [changeset:"d9a20573f473cc7389004470999b8a318aa6b3f2/ghc"]: {{{ #!CommitTicketReference repository="ghc" revision="d9a20573f473cc7389004470999b8a318aa6b3f2" Make Prelude.signum handle -0.0 correctly (#7858) Summary: Make the `Float` and `Double` implementations of `signum` handle -0.0 correctly per IEEE-754. This, together with "Make Prelude.abs handle -0.0 correctly (#7858)", fixes Trac #7858. Depends on D145 Signed-off-by: Alexander Berntsen <alexander@plaimi.net> Test Plan: signum of (-0.0) should be (-0.0) not 0.0. Test program: main = putStrLn $ p ++ " " ++ n where f = show . signum p = f (-0.0 :: Double) n = f (0.0 :: Double) Reviewers: ekmett, hvr, rwbarton, austin Reviewed By: austin Subscribers: phaskell, simonmar, relrod, ezyang, carter Differential Revision: https://phabricator.haskell.org/D148 GHC Trac Issues: #7858 }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7858#comment:14> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler