-toZgraph :: String -> CmmFormals -> ListGraph CmmStmt -> UniqSM CmmGraph
-toZgraph _ _ (ListGraph []) = lgraphOfAGraph 0 emptyAGraph
+toZgraph :: String -> CmmFormals -> ListGraph CmmStmt -> UniqSM (CmmStackInfo, CmmGraph)
+toZgraph _ _ (ListGraph []) =
+ do g <- lgraphOfAGraph emptyAGraph
+ return ((0, Nothing), g)