
#8066: Compiler Panic When Using Instance Derivation With Singletons ---------------------------------------+----------------------------------- Reporter: tvynr | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.6.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time crash | Unknown/Multiple Test Case: | Difficulty: Unknown Blocking: | Blocked By: | Related Tickets: ---------------------------------------+----------------------------------- Comment (by simonpj): The HEAD gives {{{ T8066.hs:42:22: No instance for (SingE QualForm (KindOf QualForm a)) arising from the 'deriving' clause of a data type declaration Possible fix: use a standalone 'deriving instance' declaration, so you can specify the instance context yourself When deriving the instance for (Show (TVar a)) }}} Does that seem more reasonable? We've fixed lots of kind-related bugs in 7.6. If the error looks ok, can we close the ticket? Simon -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8066#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler