#12234: 'deriving Eq' on recursive datatype makes ghc eat a lot of CPU and RAM -------------------------------------+------------------------------------- Reporter: slyfox | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 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: | -------------------------------------+------------------------------------- Changes (by RyanGlScott): * cc: niteria (added) Comment: Replying to [comment:7 goldfire]:
Maybe we should use "stock" for recursive newtypes?
Maybe. But it bothers me that this used to work fine in 7.10.3. I did some git archaeology and discovered that this commit ( http://git.haskell.org/ghc.git/commit/9cb192ce4b34a472041010df9c30f5d741eb02... ) is responsible for this regression, but I don't understand why a change to the digraph code led to this. niteria, any thoughts as the author of the commit? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12234#comment:8 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler