diff --git libstdc++-v3/include/bits/stl_algo.h libstdc++-v3/include/bits/stl_algo.h
index c90f479..6037044 100644
--- libstdc++-v3/include/bits/stl_algo.h
+++ libstdc++-v3/include/bits/stl_algo.h
@@ -1735,12 +1735,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 		      _RandomAccessIterator __result_first,
 		      _RandomAccessIterator __result_last)
     {
+#ifdef _GLIBCXX_CONCEPT_CHECKS
       typedef typename iterator_traits<_InputIterator>::value_type
 	_InputValueType;
       typedef typename iterator_traits<_RandomAccessIterator>::value_type
 	_OutputValueType;
-      typedef typename iterator_traits<_RandomAccessIterator>::difference_type
-	_DistanceType;
+#endif
 
       // concept requirements
       __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
@@ -1786,12 +1786,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 		      _RandomAccessIterator __result_last,
 		      _Compare __comp)
     {
+#ifdef _GLIBCXX_CONCEPT_CHECKS
       typedef typename iterator_traits<_InputIterator>::value_type
 	_InputValueType;
       typedef typename iterator_traits<_RandomAccessIterator>::value_type
 	_OutputValueType;
-      typedef typename iterator_traits<_RandomAccessIterator>::difference_type
-	_DistanceType;
+#endif
 
       // concept requirements
       __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
@@ -2020,13 +2020,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     lower_bound(_ForwardIterator __first, _ForwardIterator __last,
 		const _Tp& __val, _Compare __comp)
     {
-      typedef typename iterator_traits<_ForwardIterator>::value_type
-	_ValueType;
-
       // concept requirements
       __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
       __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
-				  _ValueType, _Tp>)
+	typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
       __glibcxx_requires_partitioned_lower_pred(__first, __last,
 						__val, __comp);
       __glibcxx_requires_irreflexive_pred2(__first, __last, __comp);
@@ -2078,12 +2075,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     upper_bound(_ForwardIterator __first, _ForwardIterator __last,
 		const _Tp& __val)
     {
-      typedef typename iterator_traits<_ForwardIterator>::value_type
-	_ValueType;
-
       // concept requirements
       __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
-      __glibcxx_function_requires(_LessThanOpConcept<_Tp, _ValueType>)
+      __glibcxx_function_requires(_LessThanOpConcept<
+	_Tp, typename iterator_traits<_ForwardIterator>::value_type>)
       __glibcxx_requires_partitioned_upper(__first, __last, __val);
       __glibcxx_requires_irreflexive2(__first, __last);
 
@@ -2111,13 +2106,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     upper_bound(_ForwardIterator __first, _ForwardIterator __last,
 		const _Tp& __val, _Compare __comp)
     {
-      typedef typename iterator_traits<_ForwardIterator>::value_type
-	_ValueType;
-
       // concept requirements
       __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
       __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
-				  _Tp, _ValueType>)
+	_Tp, typename iterator_traits<_ForwardIterator>::value_type>)
       __glibcxx_requires_partitioned_upper_pred(__first, __last,
 						__val, __comp);
       __glibcxx_requires_irreflexive_pred2(__first, __last, __comp);
@@ -2186,13 +2178,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     equal_range(_ForwardIterator __first, _ForwardIterator __last,
 		const _Tp& __val)
     {
-      typedef typename iterator_traits<_ForwardIterator>::value_type
-	_ValueType;
-
       // concept requirements
       __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
-      __glibcxx_function_requires(_LessThanOpConcept<_ValueType, _Tp>)
-      __glibcxx_function_requires(_LessThanOpConcept<_Tp, _ValueType>)
+      __glibcxx_function_requires(_LessThanOpConcept<
+	typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
+      __glibcxx_function_requires(_LessThanOpConcept<
+	_Tp, typename iterator_traits<_ForwardIterator>::value_type>)
       __glibcxx_requires_partitioned_lower(__first, __last, __val);
       __glibcxx_requires_partitioned_upper(__first, __last, __val);
       __glibcxx_requires_irreflexive2(__first, __last);
@@ -2224,15 +2215,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     equal_range(_ForwardIterator __first, _ForwardIterator __last,
 		const _Tp& __val, _Compare __comp)
     {
-      typedef typename iterator_traits<_ForwardIterator>::value_type
-	_ValueType;
-
       // concept requirements
       __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
       __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
-				  _ValueType, _Tp>)
+	typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
       __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
-				  _Tp, _ValueType>)
+	_Tp, typename iterator_traits<_ForwardIterator>::value_type>)
       __glibcxx_requires_partitioned_lower_pred(__first, __last,
 						__val, __comp);
       __glibcxx_requires_partitioned_upper_pred(__first, __last,
@@ -2261,12 +2249,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     binary_search(_ForwardIterator __first, _ForwardIterator __last,
                   const _Tp& __val)
     {
-      typedef typename iterator_traits<_ForwardIterator>::value_type
-	_ValueType;
-
       // concept requirements
       __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
-      __glibcxx_function_requires(_LessThanOpConcept<_Tp, _ValueType>)
+      __glibcxx_function_requires(_LessThanOpConcept<
+	_Tp, typename iterator_traits<_ForwardIterator>::value_type>)
       __glibcxx_requires_partitioned_lower(__first, __last, __val);
       __glibcxx_requires_partitioned_upper(__first, __last, __val);
       __glibcxx_requires_irreflexive2(__first, __last);
@@ -2297,13 +2283,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     binary_search(_ForwardIterator __first, _ForwardIterator __last,
                   const _Tp& __val, _Compare __comp)
     {
-      typedef typename iterator_traits<_ForwardIterator>::value_type
-	_ValueType;
-
       // concept requirements
       __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>)
       __glibcxx_function_requires(_BinaryPredicateConcept<_Compare,
-				  _Tp, _ValueType>)
+	_Tp, typename iterator_traits<_ForwardIterator>::value_type>)
       __glibcxx_requires_partitioned_lower_pred(__first, __last,
 						__val, __comp);
       __glibcxx_requires_partitioned_upper_pred(__first, __last,
diff --git libstdc++-v3/include/bits/stl_heap.h libstdc++-v3/include/bits/stl_heap.h
index f5e0ed3..58b9bfe 100644
--- libstdc++-v3/include/bits/stl_heap.h
+++ libstdc++-v3/include/bits/stl_heap.h
@@ -264,13 +264,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     inline void
     pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last)
     {
-      typedef typename iterator_traits<_RandomAccessIterator>::value_type
-	_ValueType;
-
       // concept requirements
       __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept<
 	    _RandomAccessIterator>)
-      __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>)
+      __glibcxx_function_requires(_LessThanComparableConcept<
+	typename iterator_traits<_RandomAccessIterator>::value_type>)
       __glibcxx_requires_non_empty_range(__first, __last);
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive(__first, __last);