1 files changed, 7 insertions, 3 deletions
diff --git a/include/clang/Analysis/Analyses/PostOrderCFGView.h b/include/clang/Analysis/Analyses/PostOrderCFGView.h
index 4e3244e7b7ca..91bf51cd613f 100644
--- a/include/clang/Analysis/Analyses/PostOrderCFGView.h
+++ b/include/clang/Analysis/Analyses/PostOrderCFGView.h
@@ -52,7 +52,7 @@ public:
       // make sure that Block is non-null.  Moreover, the CFGBlock iterator will
       // occasionally hand out null pointers for pruned edges, so we catch those
       // here.
-      if (Block == 0)
+      if (!Block)
         return false;  // if an edge is trivially false.
       if (VisitedBlockIDs.test(Block->getBlockID()))
         return false;
@@ -76,14 +76,18 @@ private:
   BlockOrderTy BlockOrder;
 
 public:
-  typedef std::vector<const CFGBlock*>::reverse_iterator iterator;
+  typedef std::vector<const CFGBlock *>::reverse_iterator iterator;
+  typedef std::vector<const CFGBlock *>::const_reverse_iterator const_iterator;
 
   PostOrderCFGView(const CFG *cfg);
 
   iterator begin() { return Blocks.rbegin(); }
   iterator end()   { return Blocks.rend(); }
 
-  bool empty() { return begin() == end(); }
+  const_iterator begin() const { return Blocks.rbegin(); }
+  const_iterator end() const { return Blocks.rend(); }
+
+  bool empty() const { return begin() == end(); }
 
   struct BlockOrderCompare;
   friend struct BlockOrderCompare;