-- fixed point iteratively starting from somewhere other than bottom
-- (as in the reachability analysis done for proc points).
-class (Outputable m, Outputable l, LastNode l, Outputable (LGraph m l)) => DebugNodes m l
+class (Outputable m, Outputable l, LastNode l) => DebugNodes m l
refine_f_anal :: (DebugNodes m l, LastNode l, Outputable a) =>
FAnalysis m l a -> LGraph m l -> DFA a () -> DFA a ()