#15164: Slowdown in ghc compile times from GHC 8.0.2 to GHC 8.2.1 when doing Called arity analysis -------------------------------------+------------------------------------- Reporter: flip101 | Owner: (none) Type: bug | Status: new Priority: highest | Milestone: 8.6.1 Component: Compiler | Version: 8.2.1 Resolution: | Keywords: Operating System: Linux | Architecture: x86_64 Type of failure: Compile-time | (amd64) performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by sgraf): The `-ddump-simpl-iterations` of Level4 in 8.4.2 has 89,000 terms and contains one gigantic top-level recursive binding. The output for 8.0.2 has 3,055 terms and more, manageable recursive top-level bindigns. That's huge. There's already a huge difference in compile-time for 8.4.2 with `-fno- call-arity` vs. 8.0.2 proper (>60s vs. 3s). -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15164#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler