diff --git a/src/Cryptol/TypeCheck/Infer.hs b/src/Cryptol/TypeCheck/Infer.hs
index 0eb0a625..bb083142 100644
--- a/src/Cryptol/TypeCheck/Infer.hs
+++ b/src/Cryptol/TypeCheck/Infer.hs
@@ -27,7 +27,7 @@ import           Cryptol.TypeCheck.Kind(checkType,checkSchema,checkTySyn,
                                           checkNewtype)
 import           Cryptol.TypeCheck.Instantiate
 import           Cryptol.TypeCheck.Depends
-import           Cryptol.TypeCheck.Subst (listSubst,apSubst,fvs,(@@))
+import           Cryptol.TypeCheck.Subst (listSubst,apSubst,(@@))
 import           Cryptol.TypeCheck.Solver.InfNat(genLog)
 import           Cryptol.Utils.Ident
 import           Cryptol.Utils.Panic(panic)
diff --git a/src/Cryptol/TypeCheck/InferTypes.hs b/src/Cryptol/TypeCheck/InferTypes.hs
index b3f237e3..0f8c7ff9 100644
--- a/src/Cryptol/TypeCheck/InferTypes.hs
+++ b/src/Cryptol/TypeCheck/InferTypes.hs
@@ -20,7 +20,6 @@ module Cryptol.TypeCheck.InferTypes where
 
 import           Cryptol.TypeCheck.AST
 import           Cryptol.TypeCheck.Subst
-import           Cryptol.TypeCheck.TypeMap
 import           Cryptol.Parser.Position
 import qualified Cryptol.Parser.AST as P
 import           Cryptol.Utils.PP
diff --git a/src/Cryptol/TypeCheck/Sanity.hs b/src/Cryptol/TypeCheck/Sanity.hs
index afe48038..7d2d35bb 100644
--- a/src/Cryptol/TypeCheck/Sanity.hs
+++ b/src/Cryptol/TypeCheck/Sanity.hs
@@ -16,11 +16,11 @@ module Cryptol.TypeCheck.Sanity
 
 
 import Cryptol.TypeCheck.AST
-import Cryptol.TypeCheck.Subst(apSubst, fvs, singleSubst)
+import Cryptol.TypeCheck.Subst (apSubst, singleSubst)
 import Cryptol.Utils.Ident
 
 import qualified Data.Set as Set
-import Data.List(sort, sortBy)
+import Data.List (sort, sortBy)
 import Data.Function (on)
 import MonadLib
 import qualified Control.Applicative as A
diff --git a/src/Cryptol/TypeCheck/SimpType.hs b/src/Cryptol/TypeCheck/SimpType.hs
index c7ee58ff..9e5f8275 100644
--- a/src/Cryptol/TypeCheck/SimpType.hs
+++ b/src/Cryptol/TypeCheck/SimpType.hs
@@ -3,7 +3,7 @@ module Cryptol.TypeCheck.SimpType where
 
 import Control.Applicative((<|>))
 import Cryptol.TypeCheck.Type hiding
-  (tAdd,tSub,tMul,tDiv,tMod,tExp,tMin,tMax,tWidth,tLenFromThen,tLenFromThenTo)
+  (tSub,tMul,tDiv,tMod,tExp,tMin,tWidth,tLenFromThen,tLenFromThenTo)
 import Cryptol.TypeCheck.TypePat
 import Cryptol.TypeCheck.Solver.InfNat
 import Control.Monad(msum,guard)
diff --git a/src/Cryptol/TypeCheck/SimpleSolver.hs b/src/Cryptol/TypeCheck/SimpleSolver.hs
index bc3714bc..eb6520ac 100644
--- a/src/Cryptol/TypeCheck/SimpleSolver.hs
+++ b/src/Cryptol/TypeCheck/SimpleSolver.hs
@@ -2,7 +2,7 @@
 module Cryptol.TypeCheck.SimpleSolver ( simplify , simplifyStep) where
 
 import Cryptol.TypeCheck.Type hiding
-  ( tAdd, tSub, tMul, tDiv, tMod, tExp, tMin, tMax, tWidth
+  ( tSub, tMul, tDiv, tMod, tExp, tMin, tWidth
   , tLenFromThen, tLenFromThenTo)
 import Cryptol.TypeCheck.Solver.Types
 import Cryptol.TypeCheck.Solver.Numeric.Fin(cryIsFinType)
diff --git a/src/Cryptol/TypeCheck/Solve.hs b/src/Cryptol/TypeCheck/Solve.hs
index 21db5809..d9a40301 100644
--- a/src/Cryptol/TypeCheck/Solve.hs
+++ b/src/Cryptol/TypeCheck/Solve.hs
@@ -21,7 +21,7 @@ import           Cryptol.TypeCheck.PP(pp)
 import           Cryptol.TypeCheck.AST
 import           Cryptol.TypeCheck.Monad
 import           Cryptol.TypeCheck.Subst
-                    (apSubst,fvs,singleSubst, isEmptySubst, substToList,
+                    (apSubst, singleSubst, isEmptySubst, substToList,
                           emptySubst,Subst,listSubst, (@@), Subst,
                            apSubstMaybe, substBinds)
 import qualified Cryptol.TypeCheck.SimpleSolver as Simplify
@@ -358,7 +358,7 @@ computeImprovements s gs =
                   Right ints <- Num.getIntervals s
                   return (Just (ints,su))
      case res of
-       Just (ints,su) -> return (Right su) -- ?
+       Just (_ints, su) -> return (Right su) -- ?
 {-
          | isEmptySubst su
          , (x,t) : _ <- mapMaybe (improveByDefn ints) gs ->