#15125: Typeclass instance selection depends on the optimisation level -------------------------------------+------------------------------------- Reporter: nicuveo | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.2.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj): I investigated. Turns out that this is a near-dup of #14434 -- a bug in the "short-cut solver" for type classes. Happily, it was fixed six months ago, and the fix is in 8.4. I also agree with comment:4. So I'll just close this. I don't think it's worth a new regression test. If anyone reading this has a concrete suggestion for making the user manual clearer, please do re-open and off your proposed text. The user manual can always do with improvement! -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15125#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler