#11246: Regression typechecking type synonym which includes `Any`. -------------------------------------+------------------------------------- Reporter: mpickering | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.3 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: | -------------------------------------+------------------------------------- Old description:
{{{ module Foo where
import GHC.Exts
type Key a = Any }}}
produces the error message on HEAD but compiles on 7.8.3 and 7.10.1 (thanks to Reid for testing).
{{{unsafeany.hs:5:1: error: • The type family ‘Any’ should have no arguments, but has been given none • In the type synonym declaration for ‘Key’ Failed, modules loaded: none. }}}
New description: {{{ module Foo where import GHC.Exts type Key a = Any }}} produces the error message on HEAD but compiles on 7.8.3 and 7.10.1 (thanks to Reid for testing). {{{ unsafeany.hs:5:1: error: • The type family ‘Any’ should have no arguments, but has been given none • In the type synonym declaration for ‘Key’ Failed, modules loaded: none. }}} -- Comment (by mpickering): Omer comments that the bug could be caused by levity polymorphism.
mpickering: I don't quite understand what changes need to be made, but if you look at anyTyCon in TysPrim.hs you'll see that it's not updated after Richard's patch. I'm just guessing that this may be the reason because tuple tycons are changed to update the kind arguments, for example.
-- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11246#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler