#15385: -Wincomplete-patterns gets confused when combining GADTs and pattern guards -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: (none) Type: bug | Status: patch Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.5 Resolution: | Keywords: | PatternMatchWarnings Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D4968 Wiki Page: | -------------------------------------+------------------------------------- Changes (by RyanGlScott): * status: new => patch * differential: => Phab:D4968 Comment: It turns out that when GHC desugars patterns bound by pattern guards, it completely forgets to update the local dictionaries in scope with `addDictsDs`! I have no idea how this oversight went unnoticed for so long... In any case, I have a patch for this at Phab:D4968. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15385#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler