#11056: Need to generate Typable info for promoted data constructors -------------------------------------+------------------------------------- Reporter: simonpj | Owner: Type: bug | Status: new Priority: high | Milestone: 8.0.1 Component: Compiler | Version: 7.10.2 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Trac #10052 isn't relevant for HEAD, because HEAD generates implicit `Typeable` bindings for everything. But in testing {{{ {-# LANGUAGE PolyKinds, DataKinds #-} module Foo where import Data.Typeable data T = A | B Int bar :: TypeRep bar = typeRep (Proxy :: Proxy '[True]) }}} I discovered that we aren't generating tycon-rep bindings for promoted data constructors. As a result we get {{{ GHC error in desugarer lookup in Foo: Can't find interface-file declaration for variable tc'[] Probable cause: bug in .hi-boot file, or inconsistent .hi file Use -ddump-if-trace to get an idea of which file caused the error }}} In particular `TcTypeable.mkTypeableBinds` doesn't generate the bindings for the `tc'[]` and `tc':`. It's not hard to fix this, but it will add more top-level declarations for each data type decl. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11056 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler