#14266: AllowAmbiguousTypes doesn't play well with default class methods -------------------------------------+------------------------------------- Reporter: chris-martin | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.2 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 RyanGlScott): I'm incredibly confused. We seem to be talking about two different issues here: * The fact that `InstanceSigs`' "more-general-than" check gets confused when `AllowAmbiguousTypes` comes into play. That is indeed a perplexing issue, and I can't offer a suggestion on how to fix it. But it's a distraction, since I was only using `InstanceSigs` to motivate the original issue, which is... * `DefaultSignatures` gets confused when interacting with `AllowAmbiguousTypes`. We needn't bother with any sort of "more-general- than" check here, because `DefaultSignatures` emits code that doesn't use any instance signatures, right? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14266#comment:13 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler