#11066: Inacessible branch should be warning - otherwise breaks type soundness? -------------------------------------+------------------------------------- Reporter: rrnewton | Owner: (none) Type: bug | Status: new Priority: high | Milestone: 8.6.1 Component: Compiler | Version: 7.10.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Incorrect | Unknown/Multiple warning at compile-time | Test Case: Blocked By: | Blocking: Related Tickets: #8128, #8740 | Differential Rev(s): Phab:D1454 Wiki Page: | -------------------------------------+------------------------------------- Comment (by tdammers): I've been looking at this for a little while, and AFAICT, we have two actionable points at hand here: 1. "Inaccessible code" is currently an error, but it would be more reasonable to make it a warning. 2. Programs exist that the type checker currently rejects, even though we would like them to be accepted. It seems that there is no consensus on the exact conditions for this though. I believe that #1 is easy to solve, and would produce immediate benefit, while #2 needs better understanding of the actual problem. So I would suggest we tackle #1 now, and continue the discussion on #2. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11066#comment:35 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler