diff --git a/clash-ghc/src-ghc/Clash/GHC/Evaluator/Primitive.hs b/clash-ghc/src-ghc/Clash/GHC/Evaluator/Primitive.hs
index 90a122e084..45ec683114 100644
--- a/clash-ghc/src-ghc/Clash/GHC/Evaluator/Primitive.hs
+++ b/clash-ghc/src-ghc/Clash/GHC/Evaluator/Primitive.hs
@@ -4369,7 +4369,7 @@ ghcPrimStep tcm isSubj pInfo tys args mach = case primName pInfo of
     , _ : p : f : z : xs : _ <- args
     , DC _ vArgs <- xs
     , Right k' <- runExcept (tyNatSize tcm kTy)
-    -> case k'  of
+    -> error "DO WE EVER TEST THIS?" {-case k'  of
          0 -> reduce (valToTerm z)
          _ -> let (tyArgs,_)  = splitFunForallTy ty
                   (tyArgs',_) = splitFunForallTy (Either.rights tyArgs !! 2)
@@ -4405,7 +4405,7 @@ ghcPrimStep tcm isSubj pInfo tys args mach = case primName pInfo of
                                        ,Left (valToTerm z)
                                        ,Left (Either.lefts vArgs !! 2)
                                        ])
-                         ]
+                         ] -}
     where
       is0 = mScopeNames mach
   "Clash.Sized.Vector.dtfold"