#14253: Pattern match checker mistakenly concludes pattern match on pattern synonym is unreachable -------------------------------------+------------------------------------- Reporter: bgamari | Owner: (none) Type: bug | Status: new Priority: high | Milestone: 8.4.1 Component: Compiler | Version: 8.2.1 Resolution: | Keywords: | PatternSynonyms, | PatternMatchWarnings Operating System: Unknown/Multiple | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj): I'm puzzled though. The `{-# COMPLETE MkT1 #-}` pragma seems like a manifest lie. It claims that any matching on `MkT2` is inaccessible doesn't it? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14253#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler