#13976: Defined but not used warning on records used by servant-client -------------------------------------+------------------------------------- Reporter: matthewleon | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- When generating an HTTP client through the servant-client lib (https://hackage.haskell.org/package/servant-client), if the various API record accessors go unused elsewhere, -Wunused-top-binds will generate warnings of the style "Defined but not used: `{accessor}`. I believe this is somewhat misleading, as the accessors are indeed "used" in the process of generating the client. Some sample code that will generate a warning for the `release` accessor: {{{ type API = "release" :> Capture "mbid" Mbid :> Get '[JSON] Listing type Mbid = UUID data Listing = Listing { release :: Text } deriving (Show, Generic) instance FromJSON Listing coverArtArchiveAPI :: Proxy API coverArtArchiveAPI = Proxy getListing :: Mbid -> ClientM Listing getListing = client coverArtArchiveAPI }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13976 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler