diff --git a/include/llvm/ADT/DepthFirstIterator.h b/include/llvm/ADT/DepthFirstIterator.h
index c5f246c33e9..5f2df2a17e4 100644
--- a/include/llvm/ADT/DepthFirstIterator.h
+++ b/include/llvm/ADT/DepthFirstIterator.h
@@ -34,7 +34,6 @@
 #define LLVM_ADT_DEPTHFIRSTITERATOR_H
 
 #include "llvm/ADT/GraphTraits.h"
-#include "llvm/ADT/iterator.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/PointerIntPair.h"
 #include <set>
@@ -63,9 +62,11 @@ public:
 template<class GraphT,
 class SetType = llvm::SmallPtrSet<typename GraphTraits<GraphT>::NodeType*, 8>,
          bool ExtStorage = false, class GT = GraphTraits<GraphT> >
-class df_iterator : public forward_iterator<typename GT::NodeType, ptrdiff_t>,
+class df_iterator : public std::iterator<std::forward_iterator_tag,
+                                         typename GT::NodeType, ptrdiff_t>,
                     public df_iterator_storage<SetType, ExtStorage> {
-  typedef forward_iterator<typename GT::NodeType, ptrdiff_t> super;
+  typedef std::iterator<std::forward_iterator_tag,
+                        typename GT::NodeType, ptrdiff_t> super;
 
   typedef typename GT::NodeType          NodeType;
   typedef typename GT::ChildIteratorType ChildItTy;
diff --git a/include/llvm/ADT/EquivalenceClasses.h b/include/llvm/ADT/EquivalenceClasses.h
index 6e00a217beb..766d0c8a781 100644
--- a/include/llvm/ADT/EquivalenceClasses.h
+++ b/include/llvm/ADT/EquivalenceClasses.h
@@ -15,7 +15,6 @@
 #ifndef LLVM_ADT_EQUIVALENCECLASSES_H
 #define LLVM_ADT_EQUIVALENCECLASSES_H
 
-#include "llvm/ADT/iterator.h"
 #include "llvm/Support/DataTypes.h"
 #include <set>
 
@@ -234,8 +233,8 @@ public:
     return L1;
   }
 
-  class member_iterator : public forward_iterator<ElemTy, ptrdiff_t> {
-    typedef forward_iterator<const ElemTy, ptrdiff_t> super;
+  class member_iterator : public std::iterator<std::forward_iterator_tag, ElemTy, ptrdiff_t> {
+    typedef std::iterator<std::forward_iterator_tag, ElemTy, ptrdiff_t> super;
     const ECValue *Node;
     friend class EquivalenceClasses;
   public:
@@ -249,7 +248,7 @@ public:
 
     reference operator*() const {
       assert(Node != 0 && "Dereferencing end()!");
-      return Node->getData();
+      return const_cast<reference>(Node->getData()); // FIXME
     }
     reference operator->() const { return operator*(); }
 
diff --git a/include/llvm/ADT/PostOrderIterator.h b/include/llvm/ADT/PostOrderIterator.h
index 227472b2dd7..5760b2b552c 100644
--- a/include/llvm/ADT/PostOrderIterator.h
+++ b/include/llvm/ADT/PostOrderIterator.h
@@ -17,7 +17,6 @@
 #define LLVM_ADT_POSTORDERITERATOR_H
 
 #include "llvm/ADT/GraphTraits.h"
-#include "llvm/ADT/iterator.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include <set>
 #include <stack>
@@ -43,9 +42,9 @@ template<class GraphT,
   class SetType = llvm::SmallPtrSet<typename GraphTraits<GraphT>::NodeType*, 8>,
   bool ExtStorage = false,
   class GT = GraphTraits<GraphT> >
-class po_iterator : public forward_iterator<typename GT::NodeType, ptrdiff_t>,
+class po_iterator : public std::iterator<std::forward_iterator_tag, typename GT::NodeType, ptrdiff_t>,
                     public po_iterator_storage<SetType, ExtStorage> {
-  typedef forward_iterator<typename GT::NodeType, ptrdiff_t> super;
+  typedef std::iterator<std::forward_iterator_tag, typename GT::NodeType, ptrdiff_t> super;
   typedef typename GT::NodeType          NodeType;
   typedef typename GT::ChildIteratorType ChildItTy;
 
diff --git a/include/llvm/ADT/SCCIterator.h b/include/llvm/ADT/SCCIterator.h
index fde735d1015..9ca0f1c00e7 100644
--- a/include/llvm/ADT/SCCIterator.h
+++ b/include/llvm/ADT/SCCIterator.h
@@ -22,7 +22,6 @@
 #define LLVM_ADT_SCCITERATOR_H
 
 #include "llvm/ADT/GraphTraits.h"
-#include "llvm/ADT/iterator.h"
 #include <map>
 #include <vector>
 
@@ -35,11 +34,11 @@ namespace llvm {
 ///
 template<class GraphT, class GT = GraphTraits<GraphT> >
 class scc_iterator
-  : public forward_iterator<std::vector<typename GT::NodeType>, ptrdiff_t> {
+  : public std::iterator<std::forward_iterator_tag, std::vector<typename GT::NodeType>, ptrdiff_t> {
   typedef typename GT::NodeType          NodeType;
   typedef typename GT::ChildIteratorType ChildItTy;
   typedef std::vector<NodeType*> SccTy;
-  typedef forward_iterator<SccTy, ptrdiff_t> super;
+  typedef std::iterator<std::forward_iterator_tag, std::vector<typename GT::NodeType>, ptrdiff_t> super;
   typedef typename super::reference reference;
   typedef typename super::pointer pointer;
 
diff --git a/include/llvm/ADT/STLExtras.h b/include/llvm/ADT/STLExtras.h
index 9ac73c0c96c..6f4769260aa 100644
--- a/include/llvm/ADT/STLExtras.h
+++ b/include/llvm/ADT/STLExtras.h
@@ -19,8 +19,8 @@
 
 #include <cstddef> // for std::size_t
 #include <functional>
+#include <iterator>
 #include <utility> // for std::pair
-#include "llvm/ADT/iterator.h"
 
 namespace llvm {
 
diff --git a/include/llvm/ADT/SmallVector.h b/include/llvm/ADT/SmallVector.h
index dd3a6d00603..f3b4533b942 100644
--- a/include/llvm/ADT/SmallVector.h
+++ b/include/llvm/ADT/SmallVector.h
@@ -14,7 +14,6 @@
 #ifndef LLVM_ADT_SMALLVECTOR_H
 #define LLVM_ADT_SMALLVECTOR_H
 
-#include "llvm/ADT/iterator.h"
 #include "llvm/Support/type_traits.h"
 #include <algorithm>
 #include <cassert>
diff --git a/include/llvm/ADT/ilist.h b/include/llvm/ADT/ilist.h
index 2f35a7ad25c..4560f55e52f 100644
--- a/include/llvm/ADT/ilist.h
+++ b/include/llvm/ADT/ilist.h
@@ -38,8 +38,8 @@
 #ifndef LLVM_ADT_ILIST_H
 #define LLVM_ADT_ILIST_H
 
-#include "llvm/ADT/iterator.h"
 #include <cassert>
+#include <iterator>
 
 namespace llvm {
 
@@ -140,11 +140,11 @@ struct ilist_traits<const Ty> : public ilist_traits<Ty> {};
 //
 template<typename NodeTy>
 class ilist_iterator
-  : public bidirectional_iterator<NodeTy, ptrdiff_t> {
+  : public std::iterator<std::bidirectional_iterator_tag, NodeTy, ptrdiff_t> {
 
 public:
   typedef ilist_traits<NodeTy> Traits;
-  typedef bidirectional_iterator<NodeTy, ptrdiff_t> super;
+  typedef std::iterator<std::bidirectional_iterator_tag, NodeTy, ptrdiff_t> super;
 
   typedef typename super::value_type value_type;
   typedef typename super::difference_type difference_type;
diff --git a/include/llvm/Analysis/AliasSetTracker.h b/include/llvm/Analysis/AliasSetTracker.h
index 82c6f392d05..793da6f6bca 100644
--- a/include/llvm/Analysis/AliasSetTracker.h
+++ b/include/llvm/Analysis/AliasSetTracker.h
@@ -20,7 +20,6 @@
 #include "llvm/Support/CallSite.h"
 #include "llvm/Support/ValueHandle.h"
 #include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/iterator.h"
 #include "llvm/ADT/ilist.h"
 #include "llvm/ADT/ilist_node.h"
 #include <vector>
@@ -159,7 +158,7 @@ public:
   void dump() const;
 
   /// Define an iterator for alias sets... this is just a forward iterator.
-  class iterator : public forward_iterator<PointerRec, ptrdiff_t> {
+  class iterator : public std::iterator<std::forward_iterator_tag, PointerRec, ptrdiff_t> {
     PointerRec *CurNode;
   public:
     explicit iterator(PointerRec *CN = 0) : CurNode(CN) {}
diff --git a/include/llvm/Analysis/ConstantsScanner.h b/include/llvm/Analysis/ConstantsScanner.h
index bac551f0492..796a942ccca 100644
--- a/include/llvm/Analysis/ConstantsScanner.h
+++ b/include/llvm/Analysis/ConstantsScanner.h
@@ -17,7 +17,6 @@
 #define LLVM_ANALYSIS_CONSTANTSSCANNER_H
 
 #include "llvm/Support/InstIterator.h"
-#include "llvm/ADT/iterator.h"
 
 namespace llvm {
 
diff --git a/include/llvm/Bitcode/BitstreamReader.h b/include/llvm/Bitcode/BitstreamReader.h
index 83d2350fe84..779ef5fa2d8 100644
--- a/include/llvm/Bitcode/BitstreamReader.h
+++ b/include/llvm/Bitcode/BitstreamReader.h
@@ -17,6 +17,7 @@
 
 #include "llvm/Bitcode/BitCodes.h"
 #include <climits>
+#include <string>
 #include <vector>
 
 namespace llvm {
diff --git a/include/llvm/CodeGen/MachineRegisterInfo.h b/include/llvm/CodeGen/MachineRegisterInfo.h
index 80c37b39ca0..0d82f4ece7c 100644
--- a/include/llvm/CodeGen/MachineRegisterInfo.h
+++ b/include/llvm/CodeGen/MachineRegisterInfo.h
@@ -16,7 +16,6 @@
 
 #include "llvm/Target/TargetRegisterInfo.h"
 #include "llvm/ADT/BitVector.h"
-#include "llvm/ADT/iterator.h"
 #include <vector>
 
 namespace llvm {
@@ -256,7 +255,7 @@ public:
   /// returns end().
   template<bool ReturnUses, bool ReturnDefs>
   class defusechain_iterator
-    : public forward_iterator<MachineInstr, ptrdiff_t> {
+    : public std::iterator<std::forward_iterator_tag, MachineInstr, ptrdiff_t> {
     MachineOperand *Op;
     explicit defusechain_iterator(MachineOperand *op) : Op(op) {
       // If the first node isn't one we're interested in, advance to one that
@@ -269,8 +268,8 @@ public:
     }
     friend class MachineRegisterInfo;
   public:
-    typedef forward_iterator<MachineInstr, ptrdiff_t>::reference reference;
-    typedef forward_iterator<MachineInstr, ptrdiff_t>::pointer pointer;
+    typedef std::iterator<std::forward_iterator_tag, MachineInstr, ptrdiff_t>::reference reference;
+    typedef std::iterator<std::forward_iterator_tag, MachineInstr, ptrdiff_t>::pointer pointer;
     
     defusechain_iterator(const defusechain_iterator &I) : Op(I.Op) {}
     defusechain_iterator() : Op(0) {}
diff --git a/include/llvm/CodeGen/ScheduleDAG.h b/include/llvm/CodeGen/ScheduleDAG.h
index f820200f99b..797c9bce95b 100644
--- a/include/llvm/CodeGen/ScheduleDAG.h
+++ b/include/llvm/CodeGen/ScheduleDAG.h
@@ -535,7 +535,7 @@ namespace llvm {
     void EmitLiveInCopies(MachineBasicBlock *MBB);
   };
 
-  class SUnitIterator : public forward_iterator<SUnit, ptrdiff_t> {
+  class SUnitIterator : public std::iterator<std::forward_iterator_tag, SUnit, ptrdiff_t> {
     SUnit *Node;
     unsigned Operand;
 
diff --git a/include/llvm/CodeGen/SelectionDAGNodes.h b/include/llvm/CodeGen/SelectionDAGNodes.h
index a5fb08f32a7..af8c833ac11 100644
--- a/include/llvm/CodeGen/SelectionDAGNodes.h
+++ b/include/llvm/CodeGen/SelectionDAGNodes.h
@@ -22,7 +22,6 @@
 #include "llvm/Constants.h"
 #include "llvm/ADT/FoldingSet.h"
 #include "llvm/ADT/GraphTraits.h"
-#include "llvm/ADT/iterator.h"
 #include "llvm/ADT/ilist_node.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/STLExtras.h"
@@ -1129,14 +1128,14 @@ public:
   /// use_iterator - This class provides iterator support for SDUse
   /// operands that use a specific SDNode.
   class use_iterator
-    : public forward_iterator<SDUse, ptrdiff_t> {
+    : public std::iterator<std::forward_iterator_tag, SDUse, ptrdiff_t> {
     SDUse *Op;
     explicit use_iterator(SDUse *op) : Op(op) {
     }
     friend class SDNode;
   public:
-    typedef forward_iterator<SDUse, ptrdiff_t>::reference reference;
-    typedef forward_iterator<SDUse, ptrdiff_t>::pointer pointer;
+    typedef std::iterator<std::forward_iterator_tag, SDUse, ptrdiff_t>::reference reference;
+    typedef std::iterator<std::forward_iterator_tag, SDUse, ptrdiff_t>::pointer pointer;
 
     use_iterator(const use_iterator &I) : Op(I.Op) {}
     use_iterator() : Op(0) {}
@@ -2354,7 +2353,7 @@ public:
 };
 
 
-class SDNodeIterator : public forward_iterator<SDNode, ptrdiff_t> {
+class SDNodeIterator : public std::iterator<std::forward_iterator_tag, SDNode, ptrdiff_t> {
   SDNode *Node;
   unsigned Operand;
 
diff --git a/include/llvm/CompilerDriver/CompilationGraph.h b/include/llvm/CompilerDriver/CompilationGraph.h
index 825d4c40f8a..2579b2630b0 100644
--- a/include/llvm/CompilerDriver/CompilationGraph.h
+++ b/include/llvm/CompilerDriver/CompilationGraph.h
@@ -18,7 +18,6 @@
 
 #include "llvm/ADT/GraphTraits.h"
 #include "llvm/ADT/IntrusiveRefCntPtr.h"
-#include "llvm/ADT/iterator.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/StringSet.h"
@@ -242,7 +241,7 @@ namespace llvmc {
 
 
   /// NodeChildIterator - Another auxiliary class needed by GraphTraits.
-  class NodeChildIterator : public bidirectional_iterator<Node, ptrdiff_t> {
+  class NodeChildIterator : public std::iterator<std::bidirectional_iterator_tag, Node, ptrdiff_t> {
     typedef NodeChildIterator ThisType;
     typedef Node::container_type::iterator iterator;
 
diff --git a/include/llvm/Support/CFG.h b/include/llvm/Support/CFG.h
index b0b857bf028..ca181c519cf 100644
--- a/include/llvm/Support/CFG.h
+++ b/include/llvm/Support/CFG.h
@@ -18,7 +18,6 @@
 #include "llvm/ADT/GraphTraits.h"
 #include "llvm/Function.h"
 #include "llvm/InstrTypes.h"
-#include "llvm/ADT/iterator.h"
 
 namespace llvm {
 
@@ -27,8 +26,8 @@ namespace llvm {
 //===--------------------------------------------------------------------===//
 
 template <class _Ptr,  class _USE_iterator> // Predecessor Iterator
-class PredIterator : public forward_iterator<_Ptr, ptrdiff_t> {
-  typedef forward_iterator<_Ptr, ptrdiff_t> super;
+class PredIterator : public std::iterator<std::forward_iterator_tag, _Ptr, ptrdiff_t> {
+  typedef std::iterator<std::forward_iterator_tag, _Ptr, ptrdiff_t> super;
   _USE_iterator It;
 public:
   typedef PredIterator<_Ptr,_USE_iterator> _Self;
@@ -85,10 +84,10 @@ inline pred_const_iterator pred_end(const BasicBlock *BB) {
 //===--------------------------------------------------------------------===//
 
 template <class Term_, class BB_>           // Successor Iterator
-class SuccIterator : public bidirectional_iterator<BB_, ptrdiff_t> {
+class SuccIterator : public std::iterator<std::bidirectional_iterator_tag, BB_, ptrdiff_t> {
   const Term_ Term;
   unsigned idx;
-  typedef bidirectional_iterator<BB_, ptrdiff_t> super;
+  typedef std::iterator<std::bidirectional_iterator_tag, BB_, ptrdiff_t> super;
 public:
   typedef SuccIterator<Term_, BB_> _Self;
   typedef typename super::pointer pointer;
diff --git a/include/llvm/Support/GetElementPtrTypeIterator.h b/include/llvm/Support/GetElementPtrTypeIterator.h
index e1cda75c5f6..9430477f075 100644
--- a/include/llvm/Support/GetElementPtrTypeIterator.h
+++ b/include/llvm/Support/GetElementPtrTypeIterator.h
@@ -21,8 +21,8 @@
 namespace llvm {
   template<typename ItTy = User::const_op_iterator>
   class generic_gep_type_iterator
-    : public forward_iterator<const Type *, ptrdiff_t> {
-    typedef forward_iterator<const Type*, ptrdiff_t> super;
+    : public std::iterator<std::forward_iterator_tag, const Type *, ptrdiff_t> {
+    typedef std::iterator<std::forward_iterator_tag, const Type *, ptrdiff_t> super;
 
     ItTy OpIt;
     const Type *CurTy;
diff --git a/include/llvm/Type.h b/include/llvm/Type.h
index 94ebf1e521b..9c2fae0dfb5 100644
--- a/include/llvm/Type.h
+++ b/include/llvm/Type.h
@@ -17,7 +17,6 @@
 #include "llvm/Support/DataTypes.h"
 #include "llvm/System/Atomic.h"
 #include "llvm/ADT/GraphTraits.h"
-#include "llvm/ADT/iterator.h"
 #include <string>
 #include <vector>
 
diff --git a/include/llvm/Use.h b/include/llvm/Use.h
index 489dbc50a04..00b9c437fbb 100644
--- a/include/llvm/Use.h
+++ b/include/llvm/Use.h
@@ -26,8 +26,8 @@
 #define LLVM_USE_H
 
 #include "llvm/Support/Casting.h"
-#include "llvm/ADT/iterator.h"
 #include "llvm/ADT/PointerIntPair.h"
+#include <iterator>
 
 namespace llvm {
 
@@ -158,8 +158,8 @@ template<> struct simplify_type<const Use> {
 
 
 template<typename UserTy>  // UserTy == 'User' or 'const User'
-class value_use_iterator : public forward_iterator<UserTy*, ptrdiff_t> {
-  typedef forward_iterator<UserTy*, ptrdiff_t> super;
+class value_use_iterator : public std::iterator<std::forward_iterator_tag, UserTy*, ptrdiff_t> {
+  typedef std::iterator<std::forward_iterator_tag, UserTy*, ptrdiff_t> super;
   typedef value_use_iterator<UserTy> _Self;
 
   Use *U;