#7258: Compiling DynFlags is jolly slow -------------------------------------+------------------------------------- Reporter: simonpj | Owner: simonpj Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.6.1 Resolution: | Keywords: deriving-perf Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj): Here's a mystery. * I took `t-10-getline.hs` and `t-10-getine-appl.hs` from `examples.zip` just before comment:44 * I compiled both with `-O -dshow-passes -ddump-simpl`. * Both produced ''identical'' Core. In the early stages `getline-appl` is a little bigger, but they become identical after the first run of the simplifier following specialise/float-out. (I.e. early) I am at a loss for how to reconcile these results with the dramatically worse compile times for `getline` compared with `getline-appl` reported in the graph plot in comment:43. Tobias, any ideas? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/7258#comment:49 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler