defaultDefaultTys = [integerTy, doubleTy]
mkImpInstEnv :: DynFlags -> ExternalPackageState -> HomePackageTable -> InstEnv
+-- At the moment we (wrongly) build an instance environment from all the
+-- modules we have already compiled:
+-- (a) eps_inst_env from the external package state
+-- (b) all the md_insts in the home package table
+-- We should really only get instances from modules below us in the
+-- module import tree.
mkImpInstEnv dflags eps hpt
= foldModuleEnv (add . md_insts . hm_details)
(eps_inst_env eps)