#8173: GHC uses nub -------------------------------------+------------------------------------- Reporter: nh2 | Owner: leroux Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.6.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Unknown/Multiple Type of failure: Compile-time | Difficulty: Moderate (less performance bug | than a day) Test Case: | Blocked By: Blocking: | Related Tickets: -------------------------------------+------------------------------------- Comment (by simonpj): You don't want to compare the performance of the compiled nofib programs. After all, they should be bit-for-bit identical whether GHC internally uses `nub` or `nubOrd`! What you want to compare is the compile time! The compile times are in the nofib logs, and `nofib-analyse` should compare them, but in the log you attach it says `(no modules compiled)`. I don't know why. In any case, the differences in compile times will probably be mostly noise (a tiny difference in a large number, measured to only 0.1s precision or whatever). You might instead want to focus on the amount of space allocated by GHC as it compiles. That is at least precise and repeatable. I'm not sure if the nofib infrastructure measures these. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8173#comment:8 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler