The difference that made me try the package-db route was that it seems (from a fair amount of experimentation) that you get checkFlag=False when
#15599: typeclass inference depends on whether a module is exposed. -------------------------------------+------------------------------------- Reporter: gleachkr | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.2.3 Component: Compiler | Version: 8.2.2 Resolution: | Keywords: Operating System: Linux | Architecture: Type of failure: Incorrect result | Unknown/Multiple at runtime | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj): the modules from GHC-Repro are not compiled by ghci, but just included, What does "just included" mean? Can you give a sequence of ghc commands that demonstrates the problem? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15599#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler