#10347: Spurious "unused constructor" warning with Coercible -------------------------------------+------------------------------------- Reporter: goldfire | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.11 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: Incorrect | Test Case: warning at compile-time | typecheck/should_compile/T10347 Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by -Jie-): We ran into the same issue in our project. Simplified version: {{{ module Test (test) where import Data.Coerce (coerce) newtype N = N Int data Test = Test N test :: Test test = Test $ coerce (0 :: Int) }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10347#comment:12 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler