#10598: DeriveAnyClass and GND don't work well together -------------------------------------+------------------------------------- Reporter: osa1 | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.11 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: None/Unknown | Unknown/Multiple Blocked By: | Test Case: Related Tickets: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- Comment (by goldfire): I'm a little confused here. Why is `DeriveAnyClass` failing here? From the user manual, it seems `DeriveAnyClass` should ''always'' succeed. I think the first step in understanding this all is to figure that out. I've hunted around (wiki:Commentary/Compiler/GenericDeriving#Usingstandardderivingforgenericfunctions and #5462) but I haven't found a proper specification of the feature. It certainly isn't in the user manual. Between those two links, one says that ''any'' class can be derived, and the other requires a default. Perhaps it's the latter. Does anyone out there know? Or do you want to go spelunking through the code? One way or the other, we should disentangle this and write up a specification. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10598#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler