Fix warnings

haddock-api/src/Haddock/Convert.hs

@@ -235,7 +235,6 @@ synifyTyCon coax tc
   use_gadt_syntax = any (not . isVanillaDataCon) (tyConDataCons tc)
   consRaw = map (synifyDataCon use_gadt_syntax) (tyConDataCons tc)
   cons = rights consRaw
-  dataConErrs = lefts consRaw
   -- "deriving" doesn't affect the signature, no need to specify any.
   alg_deriv = Nothing
   defn = HsDataDefn { dd_ND      = alg_nd
@@ -248,7 +247,7 @@ synifyTyCon coax tc
   [] -> return $
         DataDecl { tcdLName = name, tcdTyVars = tyvars, tcdDataDefn = defn
                  , tcdFVs = placeHolderNames }
-  ms -> Left $ unlines dataConErrs
+  dataConErrs -> Left $ unlines dataConErrs
 
 -- User beware: it is your responsibility to pass True (use_gadt_syntax)
 -- for any constructor that would be misrepresented by omitting its

haddock-api/src/Haddock/Interface/AttachInstances.hs

@@ -25,14 +25,13 @@ import Data.Function (on)
 import qualified Data.Map as Map
 import qualified Data.Set as Set
 
-import Bag (listToBag)
 import Class
 import DynFlags
 import ErrUtils
 import FamInstEnv
 import FastString
 import GHC
-import GhcMonad (withSession, logWarnings)
+import GhcMonad (withSession)
 import Id
 import InstEnv
 import MonadUtils (liftIO)

haddock-api/src/Haddock/Interface/Create.hs

@@ -620,8 +620,8 @@ hiDecl dflags t = do
       return Nothing
     Just x -> case tyThingToLHsDecl x of
       Left m -> liftErrMsg (tell [bugWarn m]) >> return Nothing
-      Right (m, t) -> liftErrMsg (tell $ map bugWarn m)
-                      >> return (Just $ noLoc t)
+      Right (m, t') -> liftErrMsg (tell $ map bugWarn m)
+                      >> return (Just $ noLoc t')
     where
       warnLine x = O.text "haddock-bug:" O.<+> O.text x O.<>
                    O.comma O.<+> O.quotes (O.ppr t) O.<+>