Generate the empty type for State types.

diff --git a/cλash/CLasH/VHDL/VHDLTools.hs b/cλash/CLasH/VHDL/VHDLTools.hs
index ed4d7f6b3bc4608e0a0699102eb576d50c3da642..4b728e858af6f67f0af5c3ee41d3b5719daa8121 100644 (file)
--- a/cλash/CLasH/VHDL/VHDLTools.hs
+++ b/cλash/CLasH/VHDL/VHDLTools.hs
@@ -317,6 +317,8 @@ vhdl_ty_either ty = do
 -- Construct a new VHDL type for the given Haskell type. Returns an error
 -- message or the resulting typemark and typedef.
 construct_vhdl_ty :: Type.Type -> TypeSession (Either String (Maybe (AST.TypeMark, Either AST.TypeDef AST.SubtypeIn)))
+-- State types don't generate VHDL
+construct_vhdl_ty ty | isStateType ty = return $ Right Nothing
 construct_vhdl_ty ty = do
   case Type.splitTyConApp_maybe ty of
     Just (tycon, args) -> do