#8979: matching type function application with type synonym application --------------------------------------------+------------------------------ Reporter: Lemming | Owner: Type: bug | Status: closed Priority: normal | Milestone: Component: Compiler (Type checker) | Version: 7.8.1 Resolution: duplicate | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: None/Unknown | Unknown/Multiple Test Case: | Difficulty: Unknown Blocking: | Blocked By: | Related Tickets: --------------------------------------------+------------------------------ Comment (by Simon Peyton Jones <simonpj@…>): In [changeset:"b8132a9d2fdb93c5d30107b1d531dd73ac27b262/ghc"]: {{{ #!CommitTicketReference repository="ghc" revision="b8132a9d2fdb93c5d30107b1d531dd73ac27b262" Fix egregious blunder in the type flattener In tidying up the flattener I introduced an error that no regression test caught, giving rise to Trac #8978, #8979. It shows up if you have a type synonym whose RHS mentions type functions, such sas type family F a type T a = (F a, a) -- This synonym isn't properly flattened The fix is easy, but sadly the bug is in the released GHC 7.8.1 }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8979#comment:3> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler