[PATCH] Re-implement predefined operators

François Dumont frs.dumont@gmail.com
Mon Oct 7 17:11:35 GMT 2024


Same version but this time I can confirm that I've run all testsuite in 
C++98 and default -std modes x64 Linux.

François


On 25/09/2024 06:59, François Dumont wrote:
> Here is a refreshed version due to a conflict with recent changes.
>
> François
>
>
> On 07/08/2024 15:39, François Dumont wrote:
>> Hi
>>
>> For recall and updated patch following latest algo changes. I've also 
>> limited my changes to make the patch smaller.
>>
>> François
>>
>>
>> On 05/06/2024 18:56, François Dumont wrote:
>>> Hi
>>>
>>> With the recent fixes to std::vector implementation all 
>>> 23_containers and 25_algorithms tests are passing in C++98 and C++20 
>>> modes.
>>>
>>> libstdc++: Reimplement __gnu_cxx::__ops operators
>>>
>>> Replace functors using iterators as input to adopt functors that are
>>> matching the same Standard expectations as the ones imposed on 
>>> functor-aware
>>> algos. It forces to have iterators dereferenced at algo level and 
>>> not in the
>>> predefined functors anymore.
>>>
>>> Also make sure that in algos implementation details functors are 
>>> passed by
>>> reference rather than by copy.
>>>
>>> libstdc++-v3/ChangeLog:
>>>
>>>         * include/bits/move.h
>>>         (_GLIBCXX_FWDREF): Now substituted by a lvalue-reference in 
>>> pre-c++11 mode.
>>>         (_GLIBCXX_FWDCREF): New macro, substituted by a const lvalue 
>>> reference in
>>>         pre-c++11 mode.
>>>         * include/bits/stl_tree.h: Replace _GLIBCXX_FWDREF usage by 
>>> _GLIBCXX_FWDCREF.
>>>         * include/std/functional: Include predefined_ops.h.
>>>         (_Not_fn): Move to...
>>>         * include/bits/predefined_ops.h: ...here, and expose a version
>>>         in pre-C++14 mode.
>>>         (__not_fn): New, use latter.
>>>         (_Iter_less_iter, _Iter_less_val, _Val_less_iter, 
>>> _Iter_equal_to_iter)
>>>         (_Iter_equal_to_val, _Iter_comp_iter, _Iter_comp_val, 
>>> _Val_comp_iter)
>>>         (_Iter_equals_val, _Iter_equals_iter, _Iter_pred, 
>>> _Iter_comp_val)
>>>         (_Iter_comp_to_val, _Iter_comp_to_iter, _Iter_negate): Remove.
>>>         (__iter_less_iter, __iter_less_val, __iter_comp_val, 
>>> __val_less_iter)
>>>         (__val_comp_iter, __iter_equal_to_iter, __iter_equal_to_val, 
>>> __iter_comp_iter)
>>>         (__val_comp_iter, __iter_equals_val, __iter_comp_iter, 
>>> __pred_iter): Remove.
>>>         (_Less, _Equal_to, _Equal_to_val, _Comp_val): New.
>>>         (__less, __equal_to, __comp_val): New.
>>>         * include/bits/stl_algo.h: Adapt all algos to use new 
>>> __gnu_cxx::__ops operators.
>>>         When possible use std::move to pass predicates between 
>>> routines.
>>>         * include/bits/stl_algobase.h: Likewise.
>>>         * include/bits/stl_heap.h: Likewise.
>>>         * include/std/deque: Cleanup usage of __gnu_cxx::__ops 
>>> operators. Replace usage of
>>>         std::ref by std::move to pass predicate to std::__remove_if.
>>>         * include/std/string: Likewise.
>>>         * include/std/vector: Likewise.
>>>         * src/c++17/memory_resource.cc: Include <functional>.
>>>
>>> I'm not proud of the _GLIBCXX_FWDCREF but I'm sure you'll find a 
>>> better name !
>>>
>>> Ok to commit once I've completed the test coverage ?
>>>
>>> François
-------------- next part --------------
diff --git a/libstdc++-v3/include/bits/move.h b/libstdc++-v3/include/bits/move.h
index 8397a01b632..3300f0dcf9f 100644
--- a/libstdc++-v3/include/bits/move.h
+++ b/libstdc++-v3/include/bits/move.h
@@ -182,10 +182,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   /// @} group utilities
 
 #define _GLIBCXX_FWDREF(_Tp) _Tp&&
+#define _GLIBCXX_FWDCREF(_Tp) _Tp&&
 #define _GLIBCXX_MOVE(__val) std::move(__val)
 #define _GLIBCXX_FORWARD(_Tp, __val) std::forward<_Tp>(__val)
 #else
-#define _GLIBCXX_FWDREF(_Tp) const _Tp&
+#define _GLIBCXX_FWDREF(_Tp) _Tp&
+#define _GLIBCXX_FWDCREF(_Tp) const _Tp&
 #define _GLIBCXX_MOVE(__val) (__val)
 #define _GLIBCXX_FORWARD(_Tp, __val) (__val)
 #endif
diff --git a/libstdc++-v3/include/bits/predefined_ops.h b/libstdc++-v3/include/bits/predefined_ops.h
index f72d511210a..cb9017b6840 100644
--- a/libstdc++-v3/include/bits/predefined_ops.h
+++ b/libstdc++-v3/include/bits/predefined_ops.h
@@ -31,377 +31,523 @@
 #define _GLIBCXX_PREDEFINED_OPS_H	1
 
 #include <bits/move.h>
+#include <bits/stl_iterator_base_types.h>
+
+#if __cplusplus >= 201103L
+# include <bits/invoke.h>
+#endif
 
 namespace __gnu_cxx
 {
 namespace __ops
 {
-  struct _Iter_less_iter
+#if __cplusplus >= 201103L
+  struct _Less
   {
-    template<typename _Iterator1, typename _Iterator2>
+    template<typename _Lhs, typename _Rhs>
       _GLIBCXX14_CONSTEXPR
       bool
-      operator()(_Iterator1 __it1, _Iterator2 __it2) const
-      { return *__it1 < *__it2; }
+      operator()(_Lhs&& __lhs, _Rhs&& __rhs) const
+      noexcept( noexcept(__lhs < __rhs) )
+      { return __lhs < __rhs; }
   };
+#else
+  template<typename _Ref1, typename _Ref2>
+    struct _LessRefs
+    {
+      bool
+      operator()(_Ref1 __lhs, _Ref2 __rhs) const
+      { return __lhs < __rhs; }
 
-  _GLIBCXX14_CONSTEXPR
-  inline _Iter_less_iter
-  __iter_less_iter()
-  { return _Iter_less_iter(); }
+      bool
+      operator()(_Ref2 __lhs, _Ref1 __rhs) const
+      { return __lhs < __rhs; }
 
-  struct _Iter_less_val
-  {
-#if __cplusplus >= 201103L
-    constexpr _Iter_less_val() = default;
-#else
-    _Iter_less_val() { }
-#endif
+      bool
+      operator()(_Ref1 __lhs, _Ref1 __rhs) const
+      { return __lhs < __rhs; }
 
-    _GLIBCXX20_CONSTEXPR
-    explicit
-    _Iter_less_val(_Iter_less_iter) { }
+      bool
+      operator()(_Ref2 __lhs, _Ref2 __rhs) const
+      { return __lhs < __rhs; }
+    };
 
-    template<typename _Iterator, typename _Value>
-      _GLIBCXX20_CONSTEXPR
+  template<typename _Ref>
+    struct _LessRefs<_Ref, _Ref>
+    {
       bool
-      operator()(_Iterator __it, _Value& __val) const
-      { return *__it < __val; }
-  };
+      operator()(_Ref __lhs, _Ref __rhs) const
+      { return __lhs < __rhs; }
+    };
 
-  _GLIBCXX20_CONSTEXPR
-  inline _Iter_less_val
-  __iter_less_val()
-  { return _Iter_less_val(); }
+  template<typename _Ite1, typename _Ite2>
+    struct _Less
+    : _LessRefs<typename std::iterator_traits<_Ite1>::reference,
+		typename std::iterator_traits<_Ite2>::reference>
+    { };
+
+  template<typename _Ite>
+    struct _LessCRef
+    : _LessRefs<typename std::iterator_traits<_Ite>::reference,
+		const typename std::iterator_traits<_Ite>::value_type&>
+    { };
+#endif
 
-  _GLIBCXX20_CONSTEXPR
-  inline _Iter_less_val
-  __iter_comp_val(_Iter_less_iter)
-  { return _Iter_less_val(); }
+#if __cplusplus >= 201103L
+  template<typename _Ite1, typename _Ite2>
+    constexpr _Less
+    __less(_Ite1, _Ite2) noexcept
+    { return _Less{}; }
+
+  constexpr _Less
+  __less() noexcept
+  { return _Less{}; }
+#else
+  template<typename _Ite1, typename _Ite2>
+    inline _Less<_Ite1, _Ite2>
+    __less(_Ite1, _Ite2)
+    { return _Less<_Ite1, _Ite2>(); }
+#endif
 
-  struct _Val_less_iter
-  {
 #if __cplusplus >= 201103L
-    constexpr _Val_less_iter() = default;
+  template<typename _Ite>
+    constexpr _Less
+    __less(_Ite) noexcept
+    { return _Less{}; }
 #else
-    _Val_less_iter() { }
+  template<typename _Ite>
+    inline _LessCRef<_Ite>
+    __less(_Ite)
+    { return _LessCRef<_Ite>(); }
 #endif
 
-    _GLIBCXX20_CONSTEXPR
-    explicit
-    _Val_less_iter(_Iter_less_iter) { }
+#if __cplusplus >= 201103L
+  template<typename _Comp, typename _Ite1, typename _Ite2>
+    constexpr _Comp&&
+    __less(_Comp&& __comp, _Ite1, _Ite2) noexcept
+    { return std::forward<_Comp>(__comp); }
+#else
+  template<typename _Comp, typename _Ite1, typename _Ite2>
+    inline _Comp
+    __less(_Comp __comp, _Ite1, _Ite2)
+    { return __comp; }
+
+  template<typename _LessRef1, typename _LessRef2, typename _Ite1, typename _Ite2>
+    inline _Less<_Ite1, _Ite2>
+    __less(const _LessRefs<_LessRef1, _LessRef2>&, _Ite1, _Ite2)
+    { return _Less<_Ite1, _Ite2>(); }
+#endif
 
-    template<typename _Value, typename _Iterator>
-      _GLIBCXX20_CONSTEXPR
-      bool
-      operator()(_Value& __val, _Iterator __it) const
-      { return __val < *__it; }
-  };
+#if __cplusplus < 201103L
+  template<typename _Ite, typename _Val>
+    struct _LessVal : _LessRefs<typename std::iterator_traits<_Ite>::reference,
+			      _Val&>
+    { };
+#endif
 
-  _GLIBCXX20_CONSTEXPR
-  inline _Val_less_iter
-  __val_less_iter()
-  { return _Val_less_iter(); }
+#if __cplusplus >= 201103L
+  template<typename _Ite, typename _Val>
+    constexpr _Less
+    __less_val(_Ite, _Val&&) noexcept
+    { return _Less{}; }
+#else
+  template<typename _Ite, typename _Val>
+    inline _LessVal<_Ite, _Val>
+    __less_val(_Ite, _Val&)
+    { return _LessVal<_Ite, _Val>(); }
+#endif
 
-  _GLIBCXX20_CONSTEXPR
-  inline _Val_less_iter
-  __val_comp_iter(_Iter_less_iter)
-  { return _Val_less_iter(); }
+#if __cplusplus >= 201103L
+  template<typename _Comp, typename _Ite, typename _Val>
+    constexpr _Comp&&
+    __less_val(_Comp&& __comp, _Ite, _Val&&) noexcept
+    { return std::forward<_Comp>(__comp); }
+#else
+  template<typename _Comp, typename _Ite, typename _Val>
+    inline _Comp
+    __less_val(_Comp __comp, _Ite, _Val&)
+    { return __comp; }
+
+  template<typename _Ref1, typename _Ref2, typename _Ite, typename _Val>
+    inline _LessVal<_Ite, _Val>
+    __less_val(const _LessRefs<_Ref1, _Ref2>&, _Ite, _Val&)
+    { return _LessVal<_Ite, _Val>(); }
+#endif
 
-  struct _Iter_equal_to_iter
+#if __cplusplus >= 201103L
+  struct _EqualTo
   {
-    template<typename _Iterator1, typename _Iterator2>
+    template<typename _Lhs, typename _Rhs>
       _GLIBCXX20_CONSTEXPR
       bool
-      operator()(_Iterator1 __it1, _Iterator2 __it2) const
-      { return *__it1 == *__it2; }
+      operator()(_Lhs&& __lhs, _Rhs&& __rhs) const
+      noexcept( noexcept(__lhs == __rhs) )
+      { return __lhs == __rhs; }
   };
-
-  _GLIBCXX20_CONSTEXPR
-  inline _Iter_equal_to_iter
-  __iter_equal_to_iter()
-  { return _Iter_equal_to_iter(); }
-
-  struct _Iter_equal_to_val
-  {
-    template<typename _Iterator, typename _Value>
-      _GLIBCXX20_CONSTEXPR
+#else
+  template<typename _Ref1, typename _Ref2>
+    struct _EqualToRefs
+    {
       bool
-      operator()(_Iterator __it, _Value& __val) const
-      { return *__it == __val; }
-  };
-
-  _GLIBCXX20_CONSTEXPR
-  inline _Iter_equal_to_val
-  __iter_equal_to_val()
-  { return _Iter_equal_to_val(); }
-
-  _GLIBCXX20_CONSTEXPR
-  inline _Iter_equal_to_val
-  __iter_comp_val(_Iter_equal_to_iter)
-  { return _Iter_equal_to_val(); }
+      operator()(_Ref1 __lhs, _Ref2 __rhs) const
+      { return __lhs == __rhs; }
 
-  template<typename _Compare>
-    struct _Iter_comp_iter
-    {
-      _Compare _M_comp;
+      bool
+      operator()(_Ref2 __lhs, _Ref1 __rhs) const
+      { return __lhs == __rhs; }
 
-      explicit _GLIBCXX14_CONSTEXPR
-      _Iter_comp_iter(_Compare __comp)
-	: _M_comp(_GLIBCXX_MOVE(__comp))
-      { }
+      bool
+      operator()(_Ref1 __lhs, _Ref1 __rhs) const
+      { return __lhs == __rhs; }
 
-      template<typename _Iterator1, typename _Iterator2>
-        _GLIBCXX14_CONSTEXPR
-        bool
-        operator()(_Iterator1 __it1, _Iterator2 __it2)
-        { return bool(_M_comp(*__it1, *__it2)); }
+      bool
+      operator()(_Ref2 __lhs, _Ref2 __rhs) const
+      { return __lhs == __rhs; }
     };
 
-  template<typename _Compare>
-    _GLIBCXX14_CONSTEXPR
-    inline _Iter_comp_iter<_Compare>
-    __iter_comp_iter(_Compare __comp)
-    { return _Iter_comp_iter<_Compare>(_GLIBCXX_MOVE(__comp)); }
-
-  template<typename _Compare>
-    struct _Iter_comp_val
+  template<typename _Ref>
+    struct _EqualToRefs<_Ref, _Ref>
     {
-      _Compare _M_comp;
-
-      _GLIBCXX20_CONSTEXPR
-      explicit
-      _Iter_comp_val(_Compare __comp)
-	: _M_comp(_GLIBCXX_MOVE(__comp))
-      { }
+      bool
+      operator()(_Ref __lhs, _Ref __rhs) const
+      { return __lhs == __rhs; }
+    };
 
-      _GLIBCXX20_CONSTEXPR
-      explicit
-      _Iter_comp_val(const _Iter_comp_iter<_Compare>& __comp)
-	: _M_comp(__comp._M_comp)
-      { }
+  template<typename _Ite1, typename _Ite2>
+    struct _EqualTo
+      : _EqualToRefs<typename std::iterator_traits<_Ite1>::reference,
+		     typename std::iterator_traits<_Ite2>::reference>
+    { };
+#endif
 
 #if __cplusplus >= 201103L
-      _GLIBCXX20_CONSTEXPR
-      explicit
-      _Iter_comp_val(_Iter_comp_iter<_Compare>&& __comp)
-	: _M_comp(std::move(__comp._M_comp))
-      { }
+  template<typename _Ite1, typename _Ite2>
+    constexpr _EqualTo
+    __equal_to(_Ite1, _Ite2) noexcept
+    { return _EqualTo{}; }
+
+  constexpr _EqualTo
+  __equal_to() noexcept
+  { return _EqualTo{}; }
+#else
+  template<typename _Ite1, typename _Ite2>
+    inline _EqualTo<_Ite1, _Ite2>
+    __equal_to(_Ite1, _Ite2)
+    { return _EqualTo<_Ite1, _Ite2>(); }
 #endif
 
-      template<typename _Iterator, typename _Value>
-	_GLIBCXX20_CONSTEXPR
-	bool
-	operator()(_Iterator __it, _Value& __val)
-	{ return bool(_M_comp(*__it, __val)); }
-    };
-
-  template<typename _Compare>
-    _GLIBCXX20_CONSTEXPR
-    inline _Iter_comp_val<_Compare>
-    __iter_comp_val(_Compare __comp)
-    { return _Iter_comp_val<_Compare>(_GLIBCXX_MOVE(__comp)); }
-
-  template<typename _Compare>
-    _GLIBCXX20_CONSTEXPR
-    inline _Iter_comp_val<_Compare>
-    __iter_comp_val(_Iter_comp_iter<_Compare> __comp)
-    { return _Iter_comp_val<_Compare>(_GLIBCXX_MOVE(__comp)); }
-
-  template<typename _Compare>
-    struct _Val_comp_iter
-    {
-      _Compare _M_comp;
-
-      _GLIBCXX20_CONSTEXPR
-      explicit
-      _Val_comp_iter(_Compare __comp)
-	: _M_comp(_GLIBCXX_MOVE(__comp))
-      { }
-
-      _GLIBCXX20_CONSTEXPR
-      explicit
-      _Val_comp_iter(const _Iter_comp_iter<_Compare>& __comp)
-	: _M_comp(__comp._M_comp)
-      { }
-
 #if __cplusplus >= 201103L
-      _GLIBCXX20_CONSTEXPR
-      explicit
-      _Val_comp_iter(_Iter_comp_iter<_Compare>&& __comp)
-	: _M_comp(std::move(__comp._M_comp))
-      { }
+  template<typename _Ite>
+    constexpr _EqualTo
+    __equal_to(_Ite) noexcept
+    { return _EqualTo{}; }
+#else
+  template<typename _Ite>
+    inline _EqualTo<_Ite, _Ite>
+    __equal_to(_Ite)
+    { return _EqualTo<_Ite, _Ite>(); }
 #endif
 
-      template<typename _Value, typename _Iterator>
-	_GLIBCXX20_CONSTEXPR
-	bool
-	operator()(_Value& __val, _Iterator __it)
-	{ return bool(_M_comp(__val, *__it)); }
-    };
-
-  template<typename _Compare>
-    _GLIBCXX20_CONSTEXPR
-    inline _Val_comp_iter<_Compare>
-    __val_comp_iter(_Compare __comp)
-    { return _Val_comp_iter<_Compare>(_GLIBCXX_MOVE(__comp)); }
+#if __cplusplus < 201103L
+  template<typename _Ite, typename _Val>
+    struct _EqualToVal
+      : _EqualToRefs<typename std::iterator_traits<_Ite>::reference, _Val&>
+    { };
+#endif
 
-  template<typename _Compare>
-    _GLIBCXX20_CONSTEXPR
-    inline _Val_comp_iter<_Compare>
-    __val_comp_iter(_Iter_comp_iter<_Compare> __comp)
-    { return _Val_comp_iter<_Compare>(_GLIBCXX_MOVE(__comp)); }
+#if __cplusplus >= 201103L
+  template<typename _Comp, typename _Ite, typename _Val>
+    constexpr _Comp&&
+    __equal_to_val(_Comp&& __comp, _Ite, _Val&&) noexcept
+    { return std::forward<_Comp>(__comp); }
+#else
+  template<typename _Comp, typename _Ite, typename _Val>
+    inline _Comp
+    __equal_to_val(_Comp __comp, _Ite, _Val&)
+    { return __comp; }
+
+  template<typename _Ref1, typename _Ref2, typename _Ite, typename _Val>
+    inline _EqualToVal<_Ite, _Val>
+    __equal_to_val(const _EqualToRefs<_Ref1, _Ref2>&, _Ite, _Val&)
+    { return _EqualToVal<_Ite, _Val>(); }
+#endif
 
-  template<typename _Value>
-    struct _Iter_equals_val
+#if __cplusplus >= 201103L
+  template<typename _Val>
+    struct _EqualVal
     {
-      _Value& _M_value;
+    private:
+      _Val _M_val;
 
-      _GLIBCXX20_CONSTEXPR
-      explicit
-      _Iter_equals_val(_Value& __value)
-	: _M_value(__value)
-      { }
+    public:
+      constexpr
+      _EqualVal(_Val __val)
+      : _M_val(__val) { }
 
-      template<typename _Iterator>
+      template<typename _Lhs>
 	_GLIBCXX20_CONSTEXPR
 	bool
-	operator()(_Iterator __it)
-	{ return *__it == _M_value; }
+	operator()(_Lhs&& __lhs) const
+	noexcept( noexcept(__lhs == _M_val) )
+	{ return __lhs == _M_val; }
     };
-
-  template<typename _Value>
-    _GLIBCXX20_CONSTEXPR
-    inline _Iter_equals_val<_Value>
-    __iter_equals_val(_Value& __val)
-    { return _Iter_equals_val<_Value>(__val); }
-
-  template<typename _Iterator1>
-    struct _Iter_equals_iter
+#else
+  template<typename _Ref, typename _Val>
+    struct _EqualValRef
     {
-      _Iterator1 _M_it1;
+    private:
+      _Val _M_val;
 
-      _GLIBCXX20_CONSTEXPR
-      explicit
-      _Iter_equals_iter(_Iterator1 __it1)
-	: _M_it1(__it1)
+    public:
+      _EqualValRef(_Val __val)
+      : _M_val(__val)
       { }
 
-      template<typename _Iterator2>
-	_GLIBCXX20_CONSTEXPR
-	bool
-	operator()(_Iterator2 __it2)
-	{ return *__it2 == *_M_it1; }
+      bool
+      operator()(_Ref __lhs) const
+      { return __lhs == _M_val; }
     };
 
-  template<typename _Iterator>
-    _GLIBCXX20_CONSTEXPR
-    inline _Iter_equals_iter<_Iterator>
-    __iter_comp_iter(_Iter_equal_to_iter, _Iterator __it)
-    { return _Iter_equals_iter<_Iterator>(__it); }
-
-  template<typename _Predicate>
-    struct _Iter_pred
+  template<typename _Ite, typename _Val>
+    struct _EqualVal
+    : _EqualValRef<typename std::iterator_traits<_Ite>::reference, _Val>
     {
-      _Predicate _M_pred;
+      typedef
+      _EqualValRef<typename std::iterator_traits<_Ite>::reference, _Val> _Base;
 
-      _GLIBCXX20_CONSTEXPR
-      explicit
-      _Iter_pred(_Predicate __pred)
-	: _M_pred(_GLIBCXX_MOVE(__pred))
+      _EqualVal(_Val __val)
+      : _Base(__val)
       { }
-
-      template<typename _Iterator>
-	_GLIBCXX20_CONSTEXPR
-	bool
-	operator()(_Iterator __it)
-	{ return bool(_M_pred(*__it)); }
     };
+#endif
 
-  template<typename _Predicate>
-    _GLIBCXX20_CONSTEXPR
-    inline _Iter_pred<_Predicate>
-    __pred_iter(_Predicate __pred)
-    { return _Iter_pred<_Predicate>(_GLIBCXX_MOVE(__pred)); }
+#if __cplusplus >= 201103L
+  template<typename _Ite, typename _Val>
+    constexpr _EqualVal<const _Val&>
+    __equal_val(_Ite, const _Val& __val) noexcept
+    {return _EqualVal<const _Val&>(__val);}
+
+  template<typename _Val>
+    constexpr _EqualVal<const _Val&>
+    __equal_val(const _Val& __val) noexcept
+    {return _EqualVal<const _Val&>(__val);}
+#else
+  template<typename _Ite, typename _Val>
+    inline _EqualVal<_Ite, const _Val&>
+    __equal_val(_Ite, const _Val& __val)
+    { return _EqualVal<_Ite, const _Val&>(__val); }
+#endif
 
-  template<typename _Compare, typename _Value>
-    struct _Iter_comp_to_val
+#if __cplusplus >= 201103L
+  template<typename _BinaryPred, typename _Val>
+    struct _CompVal
     {
-      _Compare _M_comp;
-      _Value& _M_value;
-
-      _GLIBCXX20_CONSTEXPR
-      _Iter_comp_to_val(_Compare __comp, _Value& __value)
-	: _M_comp(_GLIBCXX_MOVE(__comp)), _M_value(__value)
+      template<typename _BPred>
+	constexpr
+	_CompVal(_BPred&& __pred, _Val __val)
+	: _M_binary_pred(std::forward<_BPred>(__pred))
+	, _M_val(__val)
+	{ }
+
+      _CompVal(const _CompVal&) = default;
+      _CompVal(_CompVal&&) = default;
+      ~_CompVal() = default;
+
+      // Macro to define operator() with given cv-qualifiers ref-qualifiers,
+      // forwarding _M_binary_pred and the function arguments with the same
+      // qualifiers, and deducing the return type and exception-specification.
+# define _GLIBCXX_BINARY_PRED_CALL_OP( _QUALS )				\
+      template<typename _Arg,						\
+	       typename = std::__enable_if_t<std::__is_invocable<	\
+		 _BinaryPred _QUALS, _Arg, _Val>::value>> 	\
+	_GLIBCXX20_CONSTEXPR						\
+	bool								\
+	operator()(_Arg&& __arg) _QUALS					\
+	noexcept(std::__is_nothrow_invocable<				\
+		 _BinaryPred _QUALS, _Arg, _Val>::value)		\
+	{								\
+	  return std::__invoke(						\
+		   std::forward< _BinaryPred _QUALS >(_M_binary_pred),	\
+		   std::forward<_Arg>(__arg), _M_val);			\
+	}								\
+									\
+      template<typename _Arg,						\
+	       typename = std::__enable_if_t<!std::__is_invocable<	\
+		 _BinaryPred _QUALS, _Arg, _Val>::value>>	\
+	void operator()(_Arg&&) _QUALS = delete;
+
+      _GLIBCXX_BINARY_PRED_CALL_OP( & )
+      _GLIBCXX_BINARY_PRED_CALL_OP( const & )
+      _GLIBCXX_BINARY_PRED_CALL_OP( && )
+      _GLIBCXX_BINARY_PRED_CALL_OP( const && )
+# undef _GLIBCXX_BINARY_PRED_CALL_OP
+#else
+  template<typename _BinaryPred, typename _Ite, typename _Val>
+    struct _CompVal
+    {
+      _CompVal(_BinaryPred __pred, _Val __val)
+      : _M_binary_pred(__pred), _M_val(__val)
       { }
 
-      template<typename _Iterator>
-	_GLIBCXX20_CONSTEXPR
-	bool
-	operator()(_Iterator __it)
-	{ return bool(_M_comp(*__it, _M_value)); }
+      bool
+      operator()(typename std::iterator_traits<_Ite>::reference __lhs)
+      { return bool(_M_binary_pred(__lhs, _M_val)); }
+#endif
+
+    private:
+      _BinaryPred _M_binary_pred;
+      _Val	  _M_val;
     };
 
-  template<typename _Compare, typename _Value>
-    _Iter_comp_to_val<_Compare, _Value>
-    _GLIBCXX20_CONSTEXPR
-    __iter_comp_val(_Compare __comp, _Value &__val)
+#if __cplusplus >= 201103L
+  template<typename _BPred, typename _Ite, typename _Val>
+    _GLIBCXX20_CONSTEXPR inline
+    _CompVal<std::__decay_t<_BPred>, const _Val&>
+    __comp_val(_BPred&& __pred, _Ite, const _Val& __val)
+    noexcept(std::is_nothrow_constructible<std::__decay_t<_BPred>,
+	     _BPred&&>::value)
     {
-      return _Iter_comp_to_val<_Compare, _Value>(_GLIBCXX_MOVE(__comp), __val);
+      return
+	_CompVal<std::__decay_t<_BPred>, const _Val&>
+	(std::forward<_BPred>(__pred), __val);
     }
+#else
+  template<typename _BPred, typename _Ite, typename _Val>
+    inline _CompVal<_BPred, _Ite, const _Val&>
+    __comp_val(_BPred __pred, _Ite, const _Val& __val)
+    { return _CompVal<_BPred, _Ite, const _Val&>(__pred, __val); }
+#endif
 
-  template<typename _Compare, typename _Iterator1>
-    struct _Iter_comp_to_iter
+#if __cplusplus >= 201103L
+  template<typename _BPred, typename _InIte, typename _Ite>
+    _GLIBCXX20_CONSTEXPR inline
+    _CompVal<std::__decay_t<_BPred>,
+	     typename std::iterator_traits<_Ite>::reference>
+    __equal_ite(_BPred&& __pred, _InIte, _Ite  __ite)
+    noexcept(std::is_nothrow_constructible<std::__decay_t<_BPred>,
+	     _BPred&&>::value)
     {
-      _Compare _M_comp;
-      _Iterator1 _M_it1;
-
-      _GLIBCXX20_CONSTEXPR
-      _Iter_comp_to_iter(_Compare __comp, _Iterator1 __it1)
-	: _M_comp(_GLIBCXX_MOVE(__comp)), _M_it1(__it1)
-      { }
-
-      template<typename _Iterator2>
-	_GLIBCXX20_CONSTEXPR
-	bool
-	operator()(_Iterator2 __it2)
-	{ return bool(_M_comp(*__it2, *_M_it1)); }
-    };
+      return
+	_CompVal<std::__decay_t<_BPred>,
+		 typename std::iterator_traits<_Ite>::reference>
+	(std::forward<_BPred>(__pred), *__ite);
+    }
 
-  template<typename _Compare, typename _Iterator>
-    _GLIBCXX20_CONSTEXPR
-    inline _Iter_comp_to_iter<_Compare, _Iterator>
-    __iter_comp_iter(_Iter_comp_iter<_Compare> __comp, _Iterator __it)
+  template<typename _InIte, typename _Ite>
+    _GLIBCXX20_CONSTEXPR inline
+    _EqualVal<typename std::iterator_traits<_Ite>::reference>
+    __equal_ite(_EqualTo, _InIte, _Ite __ite)
     {
-      return _Iter_comp_to_iter<_Compare, _Iterator>(
-	  _GLIBCXX_MOVE(__comp._M_comp), __it);
+      return
+	_EqualVal<typename std::iterator_traits<_Ite>::reference>(*__ite);
+    }
+#else
+  template<typename _BPred, typename _InIte, typename _Ite>
+    inline
+      _CompVal<_BPred, _InIte, typename std::iterator_traits<_Ite>::reference>
+    __equal_ite(_BPred __pred, _InIte, _Ite __ite)
+    {
+      return
+	_CompVal<_BPred, _InIte, typename std::iterator_traits<_Ite>::reference>
+	(__pred, *__ite);
     }
 
-  template<typename _Predicate>
-    struct _Iter_negate
+  template<typename _Ref1, typename _Ref2, typename _InIte, typename _Ite>
+    inline
+      _EqualVal<_InIte, typename std::iterator_traits<_Ite>::reference>
+    __equal_ite(const _EqualToRefs<_Ref1, _Ref2>&, _InIte, _Ite __ite)
     {
-      _Predicate _M_pred;
+      return
+	_EqualVal<_InIte, typename std::iterator_traits<_Ite>::reference>
+	(*__ite);
+    }
+#endif
+} // namespace __ops
+} // namespace __gnu_cxx
 
-      _GLIBCXX20_CONSTEXPR
-      explicit
-      _Iter_negate(_Predicate __pred)
-	: _M_pred(_GLIBCXX_MOVE(__pred))
-      { }
 
-      template<typename _Iterator>
-	_GLIBCXX20_CONSTEXPR
-	bool
-	operator()(_Iterator __it)
-	{ return !bool(_M_pred(*__it)); }
+namespace std _GLIBCXX_VISIBILITY(default)
+{
+_GLIBCXX_BEGIN_NAMESPACE_VERSION
+
+#if __cplusplus >= 201103L
+  /// Generalized negator.
+  template<typename _Fn>
+    class _Not_fn
+    {
+      template<typename _Fn2, typename... _Args>
+	using __inv_res_t = typename __invoke_result<_Fn2, _Args...>::type;
+
+      template<typename _Tp>
+	static decltype(!std::declval<_Tp>())
+	_S_not() noexcept(noexcept(!std::declval<_Tp>()));
+
+    public:
+      template<typename _Fn2>
+	constexpr
+	_Not_fn(_Fn2&& __fn, int)
+	: _M_fn(std::forward<_Fn2>(__fn)) { }
+
+      _Not_fn(const _Not_fn& __fn) = default;
+      _Not_fn(_Not_fn&& __fn) = default;
+      ~_Not_fn() = default;
+
+      // Macro to define operator() with given cv-qualifiers ref-qualifiers,
+      // forwarding _M_fn and the function arguments with the same qualifiers,
+      // and deducing the return type and exception-specification.
+# define _GLIBCXX_NOT_FN_CALL_OP( _QUALS )				\
+      template<typename... _Args,					\
+	       typename = __enable_if_t<__is_invocable<_Fn _QUALS, _Args...>::value>> \
+	_GLIBCXX20_CONSTEXPR						\
+	decltype(_S_not<__inv_res_t<_Fn _QUALS, _Args...>>())		\
+	operator()(_Args&&... __args) _QUALS				\
+	noexcept(__is_nothrow_invocable<_Fn _QUALS, _Args...>::value	\
+	    && noexcept(_S_not<__inv_res_t<_Fn _QUALS, _Args...>>()))	\
+	{								\
+	  return !std::__invoke(std::forward< _Fn _QUALS >(_M_fn),	\
+				std::forward<_Args>(__args)...);	\
+	}								\
+									\
+      template<typename... _Args,					\
+	       typename = __enable_if_t<!__is_invocable<_Fn _QUALS, _Args...>::value>> \
+	void operator()(_Args&&... __args) _QUALS = delete;
+
+      _GLIBCXX_NOT_FN_CALL_OP( & )
+      _GLIBCXX_NOT_FN_CALL_OP( const & )
+      _GLIBCXX_NOT_FN_CALL_OP( && )
+      _GLIBCXX_NOT_FN_CALL_OP( const && )
+# undef _GLIBCXX_NOT_FN_CALL_OP
+#else
+  /// Generalized negator.
+  template<typename _Fn, typename _Ite>
+    class _Not_fn
+    {
+    public:
+      _Not_fn(_Fn __fn)
+      : _M_fn(__fn) { }
+
+      bool
+      operator()(typename std::iterator_traits<_Ite>::reference __arg)
+      { return !bool(_M_fn(__arg)); }
+#endif
+    private:
+      _Fn _M_fn;
     };
 
-  template<typename _Predicate>
-    _GLIBCXX20_CONSTEXPR
-    inline _Iter_negate<_Predicate>
-    __negate(_Iter_pred<_Predicate> __pred)
-    { return _Iter_negate<_Predicate>(_GLIBCXX_MOVE(__pred._M_pred)); }
+  template<typename _Fn, typename _Ite>
+    inline _GLIBCXX20_CONSTEXPR
+#if __cplusplus >= 201103L
+    _Not_fn<std::__decay_t<_Fn>>
+    __not_fn(_Fn&& __fn, _Ite)
+    noexcept(std::is_nothrow_constructible<std::__decay_t<_Fn>, _Fn&&>::value)
+    { return _Not_fn<std::__decay_t<_Fn>>{std::forward<_Fn>(__fn), 0}; }
+#else
+    _Not_fn<_Fn, _Ite>
+    __not_fn(_Fn __fn, _Ite)
+    { return _Not_fn<_Fn, _Ite>(__fn); }
+#endif
 
-} // namespace __ops
-} // namespace __gnu_cxx
+_GLIBCXX_END_NAMESPACE_VERSION
+} // namespace std
 
 #endif
diff --git a/libstdc++-v3/include/bits/stl_algo.h b/libstdc++-v3/include/bits/stl_algo.h
index a1ef665506d..5eb22ed98e1 100644
--- a/libstdc++-v3/include/bits/stl_algo.h
+++ b/libstdc++-v3/include/bits/stl_algo.h
@@ -85,21 +85,21 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   template<typename _Iterator, typename _Compare>
     _GLIBCXX20_CONSTEXPR
     void
-    __move_median_to_first(_Iterator __result,_Iterator __a, _Iterator __b,
-			   _Iterator __c, _Compare __comp)
+    __move_median_to_first(_Iterator __result, _Iterator __a, _Iterator __b,
+			   _Iterator __c, _GLIBCXX_FWDREF(_Compare) __comp)
     {
-      if (__comp(__a, __b))
+      if (__comp(*__a, *__b))
 	{
-	  if (__comp(__b, __c))
+	  if (__comp(*__b, *__c))
 	    std::iter_swap(__result, __b);
-	  else if (__comp(__a, __c))
+	  else if (__comp(*__a, *__c))
 	    std::iter_swap(__result, __c);
 	  else
 	    std::iter_swap(__result, __a);
 	}
-      else if (__comp(__a, __c))
+      else if (__comp(*__a, *__c))
 	std::iter_swap(__result, __a);
-      else if (__comp(__b, __c))
+      else if (__comp(*__b, *__c))
 	std::iter_swap(__result, __c);
       else
 	std::iter_swap(__result, __b);
@@ -110,10 +110,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     _GLIBCXX20_CONSTEXPR
     inline _InputIterator
     __find_if_not(_InputIterator __first, _InputIterator __last,
-		  _Predicate __pred)
+		  _GLIBCXX_FWDREF(_Predicate) __pred)
     {
-      return std::__find_if(__first, __last,
-			    __gnu_cxx::__ops::__negate(__pred));
+      __decltype(std::__not_fn(_GLIBCXX_FORWARD(_Predicate, __pred), __first))
+	__prd = std::__not_fn(_GLIBCXX_FORWARD(_Predicate, __pred), __first);
+      return std::__find_if(__first, __last, _GLIBCXX_MOVE(__prd));
     }
 
   /// Like find_if_not(), but uses and updates a count of the
@@ -122,10 +123,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   template<typename _InputIterator, typename _Predicate, typename _Distance>
     _GLIBCXX20_CONSTEXPR
     _InputIterator
-    __find_if_not_n(_InputIterator __first, _Distance& __len, _Predicate __pred)
+    __find_if_not_n(_InputIterator __first, _Distance& __len,
+		    _GLIBCXX_FWDREF(_Predicate) __pred)
     {
       for (; __len; --__len,  (void) ++__first)
-	if (!__pred(__first))
+	if (!__pred(*__first))
 	  break;
       return __first;
     }
@@ -152,7 +154,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     _GLIBCXX20_CONSTEXPR
     _ForwardIterator
     __search_n_aux(_ForwardIterator __first, _ForwardIterator __last,
-		   _Integer __count, _UnaryPredicate __unary_pred,
+		   _Integer __count,
+		   _GLIBCXX_FWDREF(_UnaryPredicate) __unary_pred,
 		   std::forward_iterator_tag)
     {
       __first = std::__find_if(__first, __last, __unary_pred);
@@ -162,7 +165,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	    __n = __count;
 	  _ForwardIterator __i = __first;
 	  ++__i;
-	  while (__i != __last && __n != 1 && __unary_pred(__i))
+	  while (__i != __last && __n != 1 && __unary_pred(*__i))
 	    {
 	      ++__i;
 	      --__n;
@@ -185,7 +188,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     _GLIBCXX20_CONSTEXPR
     _RandomAccessIter
     __search_n_aux(_RandomAccessIter __first, _RandomAccessIter __last,
-		   _Integer __count, _UnaryPredicate __unary_pred,
+		   _Integer __count,
+		   _GLIBCXX_FWDREF(_UnaryPredicate) __unary_pred,
 		   std::random_access_iterator_tag)
     {
       typedef typename std::iterator_traits<_RandomAccessIter>::difference_type
@@ -201,7 +205,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	  // __first here is always pointing to one past the last element of
 	  // next possible match.
 	  _RandomAccessIter __backTrack = __first; 
-	  while (__unary_pred(--__backTrack))
+	  while (__unary_pred(*(--__backTrack)))
 	    {
 	      if (--__remainder == 0)
 		return (__first - __count); // Success
@@ -217,16 +221,18 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     _ForwardIterator
     __search_n(_ForwardIterator __first, _ForwardIterator __last,
 	       _Integer __count,
-	       _UnaryPredicate __unary_pred)
+	       _GLIBCXX_FWDREF(_UnaryPredicate) __unary_pred)
     {
       if (__count <= 0)
 	return __first;
 
       if (__count == 1)
-	return std::__find_if(__first, __last, __unary_pred);
+	return std::__find_if
+	  (__first, __last, _GLIBCXX_FORWARD(_UnaryPredicate, __unary_pred));
 
-      return std::__search_n_aux(__first, __last, __count, __unary_pred,
-				 std::__iterator_category(__first));
+      return std::__search_n_aux(__first, __last, __count,
+	 _GLIBCXX_FORWARD(_UnaryPredicate, __unary_pred),
+	 std::__iterator_category(__first));
     }
 
   // find_end for forward iterators.
@@ -237,7 +243,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     __find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
 	       _ForwardIterator2 __first2, _ForwardIterator2 __last2,
 	       forward_iterator_tag, forward_iterator_tag,
-	       _BinaryPredicate __comp)
+	       _GLIBCXX_FWDREF(_BinaryPredicate) __comp)
     {
       if (__first2 == __last2)
 	return __last1;
@@ -268,7 +274,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	       _BidirectionalIterator2 __first2,
 	       _BidirectionalIterator2 __last2,
 	       bidirectional_iterator_tag, bidirectional_iterator_tag,
-	       _BinaryPredicate __comp)
+	       _GLIBCXX_FWDREF(_BinaryPredicate) __comp)
     {
       // concept requirements
       __glibcxx_function_requires(_BidirectionalIteratorConcept<
@@ -283,7 +289,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       _RevIterator2 __rlast2(__first2);
       _RevIterator1 __rresult = std::__search(_RevIterator1(__last1), __rlast1,
 					      _RevIterator2(__last2), __rlast2,
-					      __comp);
+				_GLIBCXX_FORWARD(_BinaryPredicate, __comp));
 
       if (__rresult == __rlast1)
 	return __last1;
@@ -336,10 +342,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       __glibcxx_requires_valid_range(__first1, __last1);
       __glibcxx_requires_valid_range(__first2, __last2);
 
+      __decltype(__gnu_cxx::__ops::__equal_to(__first1, __first2)) __comp =
+	__gnu_cxx::__ops::__equal_to(__first1, __first2);
       return std::__find_end(__first1, __last1, __first2, __last2,
 			     std::__iterator_category(__first1),
 			     std::__iterator_category(__first2),
-			     __gnu_cxx::__ops::__iter_equal_to_iter());
+			     __comp);
     }
 
   /**
@@ -390,7 +398,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       return std::__find_end(__first1, __last1, __first2, __last2,
 			     std::__iterator_category(__first1),
 			     std::__iterator_category(__first2),
-			     __gnu_cxx::__ops::__iter_comp_iter(__comp));
+			     _GLIBCXX_MOVE(__comp));
     }
 
 #if __cplusplus >= 201103L
@@ -410,7 +418,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
     inline bool
     all_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
-    { return __last == std::find_if_not(__first, __last, __pred); }
+    { return __last == std::find_if_not(__first, __last, std::move(__pred)); }
 
   /**
    *  @brief  Checks that a predicate is false for all the elements
@@ -428,7 +436,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
     inline bool
     none_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
-    { return __last == _GLIBCXX_STD_A::find_if(__first, __last, __pred); }
+    {
+      return
+	__last == _GLIBCXX_STD_A::find_if(__first, __last, std::move(__pred));
+    }
 
   /**
    *  @brief  Checks that a predicate is true for at least one element
@@ -447,7 +458,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
     inline bool
     any_of(_InputIterator __first, _InputIterator __last, _Predicate __pred)
-    { return !std::none_of(__first, __last, __pred); }
+    { return !std::none_of(__first, __last, std::move(__pred)); }
 
   /**
    *  @brief  Find the first element in a sequence for which a
@@ -470,8 +481,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate,
 	      typename iterator_traits<_InputIterator>::value_type>)
       __glibcxx_requires_valid_range(__first, __last);
-      return std::__find_if_not(__first, __last,
-				__gnu_cxx::__ops::__pred_iter(__pred));
+      return std::__find_if_not(__first, __last, std::move(__pred));
     }
 
   /**
@@ -494,7 +504,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       if (__first == __last)
 	return true;
       ++__first;
-      return std::none_of(__first, __last, __pred);
+      return std::none_of(__first, __last, std::move(__pred));
     }
 
   /**
@@ -541,17 +551,18 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	}
       return __first;
     }
-#endif
+#endif // C++11
 
   template<typename _InputIterator, typename _OutputIterator,
 	   typename _Predicate>
     _GLIBCXX20_CONSTEXPR
     _OutputIterator
     __remove_copy_if(_InputIterator __first, _InputIterator __last,
-		     _OutputIterator __result, _Predicate __pred)
+		     _OutputIterator __result,
+		     _GLIBCXX_FWDREF(_Predicate) __pred)
     {
       for (; __first != __last; ++__first)
-	if (!__pred(__first))
+	if (!__pred(*__first))
 	  {
 	    *__result = *__first;
 	    ++__result;
@@ -587,8 +598,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	    typename iterator_traits<_InputIterator>::value_type, _Tp>)
       __glibcxx_requires_valid_range(__first, __last);
 
-      return std::__remove_copy_if(__first, __last, __result,
-	__gnu_cxx::__ops::__iter_equals_val(__value));
+      __decltype(__gnu_cxx::__ops::__equal_val(__first, __value)) __pred =
+	__gnu_cxx::__ops::__equal_val(__first, __value);
+      return std::__remove_copy_if(__first, __last, __result, __pred);
     }
 
   /**
@@ -622,7 +634,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       __glibcxx_requires_valid_range(__first, __last);
 
       return std::__remove_copy_if(__first, __last, __result,
-				   __gnu_cxx::__ops::__pred_iter(__pred));
+				   _GLIBCXX_MOVE(__pred));
     }
 
 #if __cplusplus >= 201103L
@@ -797,8 +809,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	    typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
       __glibcxx_requires_valid_range(__first, __last);
 
-      return std::__remove_if(__first, __last,
-		__gnu_cxx::__ops::__iter_equals_val(__value));
+      __decltype(__gnu_cxx::__ops::__equal_val(__first, __value)) __comp =
+	__gnu_cxx::__ops::__equal_val(__first, __value);
+      return std::__remove_if(__first, __last, __comp);
     }
 
   /**
@@ -831,22 +844,21 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	    typename iterator_traits<_ForwardIterator>::value_type>)
       __glibcxx_requires_valid_range(__first, __last);
 
-      return std::__remove_if(__first, __last,
-			      __gnu_cxx::__ops::__pred_iter(__pred));
+      return std::__remove_if(__first, __last, _GLIBCXX_MOVE(__pred));
     }
 
   template<typename _ForwardIterator, typename _BinaryPredicate>
     _GLIBCXX20_CONSTEXPR
     _ForwardIterator
     __adjacent_find(_ForwardIterator __first, _ForwardIterator __last,
-		    _BinaryPredicate __binary_pred)
+		    _GLIBCXX_FWDREF(_BinaryPredicate) __binary_pred)
     {
       if (__first == __last)
 	return __last;
       _ForwardIterator __next = __first;
       while (++__next != __last)
 	{
-	  if (__binary_pred(__first, __next))
+	  if (__binary_pred(*__first, *__next))
 	    return __first;
 	  __first = __next;
 	}
@@ -857,7 +869,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     _GLIBCXX20_CONSTEXPR
     _ForwardIterator
     __unique(_ForwardIterator __first, _ForwardIterator __last,
-	     _BinaryPredicate __binary_pred)
+	     _GLIBCXX_FWDREF(_BinaryPredicate) __binary_pred)
     {
       // Skip the beginning, if already unique.
       __first = std::__adjacent_find(__first, __last, __binary_pred);
@@ -868,7 +880,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       _ForwardIterator __dest = __first;
       ++__first;
       while (++__first != __last)
-	if (!__binary_pred(__dest, __first))
+	if (!__binary_pred(*__dest, *__first))
 	  *++__dest = _GLIBCXX_MOVE(*__first);
       return ++__dest;
     }
@@ -899,8 +911,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 		     typename iterator_traits<_ForwardIterator>::value_type>)
       __glibcxx_requires_valid_range(__first, __last);
 
-      return std::__unique(__first, __last,
-			   __gnu_cxx::__ops::__iter_equal_to_iter());
+      __decltype(__gnu_cxx::__ops::__equal_to(__first)) __comp =
+	__gnu_cxx::__ops::__equal_to(__first);
+      return std::__unique(__first, __last, __comp);
     }
 
   /**
@@ -932,8 +945,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 		typename iterator_traits<_ForwardIterator>::value_type>)
       __glibcxx_requires_valid_range(__first, __last);
 
-      return std::__unique(__first, __last,
-			   __gnu_cxx::__ops::__iter_comp_iter(__binary_pred));
+      return std::__unique(__first, __last, _GLIBCXX_MOVE(__binary_pred));
     }
 
   /**
@@ -947,7 +959,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     _GLIBCXX20_CONSTEXPR
     _OutputIterator
     __unique_copy(_ForwardIterator __first, _ForwardIterator __last,
-		  _OutputIterator __result, _BinaryPredicate __binary_pred,
+		  _OutputIterator __result,
+		  _GLIBCXX_FWDREF(_BinaryPredicate) __binary_pred,
 		  forward_iterator_tag, output_iterator_tag)
     {
       // concept requirements -- iterators already checked
@@ -958,7 +971,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       _ForwardIterator __next = __first;
       *__result = *__first;
       while (++__next != __last)
-	if (!__binary_pred(__first, __next))
+	if (!__binary_pred(*__first, *__next))
 	  {
 	    __first = __next;
 	    *++__result = *__first;
@@ -977,7 +990,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     _GLIBCXX20_CONSTEXPR
     _OutputIterator
     __unique_copy(_InputIterator __first, _InputIterator __last,
-		  _OutputIterator __result, _BinaryPredicate __binary_pred,
+		  _OutputIterator __result,
+		  _GLIBCXX_FWDREF(_BinaryPredicate) __binary_pred,
 		  input_iterator_tag, output_iterator_tag)
     {
       // concept requirements -- iterators already checked
@@ -986,12 +1000,14 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	  typename iterator_traits<_InputIterator>::value_type>)
 
       typename iterator_traits<_InputIterator>::value_type __value = *__first;
-      __decltype(__gnu_cxx::__ops::__iter_comp_val(__binary_pred))
-	__rebound_pred
-	= __gnu_cxx::__ops::__iter_comp_val(__binary_pred);
+      __decltype(__gnu_cxx::__ops::__equal_to_val
+		 (_GLIBCXX_FORWARD(_BinaryPredicate, __binary_pred),
+		  __first, __value)) __bnry_pred =
+	__gnu_cxx::__ops::__equal_to_val
+	(_GLIBCXX_FORWARD(_BinaryPredicate, __binary_pred), __first, __value);
       *__result = __value;
       while (++__first != __last)
-	if (!__rebound_pred(__first, __value))
+	if (!__bnry_pred(*__first, __value))
 	  {
 	    __value = *__first;
 	    *++__result = __value;
@@ -1010,7 +1026,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     _GLIBCXX20_CONSTEXPR
     _ForwardIterator
     __unique_copy(_InputIterator __first, _InputIterator __last,
-		  _ForwardIterator __result, _BinaryPredicate __binary_pred,
+		  _ForwardIterator __result,
+		  _GLIBCXX_FWDREF(_BinaryPredicate) __binary_pred,
 		  input_iterator_tag, forward_iterator_tag)
     {
       // concept requirements -- iterators already checked
@@ -1019,7 +1036,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	  typename iterator_traits<_InputIterator>::value_type>)
       *__result = *__first;
       while (++__first != __last)
-	if (!__binary_pred(__result, __first))
+	if (!__binary_pred(*__result, *__first))
 	  *++__result = *__first;
       return ++__result;
     }
@@ -1404,7 +1421,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     _GLIBCXX20_CONSTEXPR
     _ForwardIterator
     __partition(_ForwardIterator __first, _ForwardIterator __last,
-		_Predicate __pred, forward_iterator_tag)
+		_GLIBCXX_FWDREF(_Predicate) __pred, forward_iterator_tag)
     {
       if (__first == __last)
 	return __first;
@@ -1430,7 +1447,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     _GLIBCXX20_CONSTEXPR
     _BidirectionalIterator
     __partition(_BidirectionalIterator __first, _BidirectionalIterator __last,
-		_Predicate __pred, bidirectional_iterator_tag)
+		_GLIBCXX_FWDREF(_Predicate) __pred, bidirectional_iterator_tag)
     {
       while (true)
 	{
@@ -1468,7 +1485,8 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     _ForwardIterator
     __stable_partition_adaptive(_ForwardIterator __first,
 				_ForwardIterator __last,
-				_Predicate __pred, _Distance __len,
+				_GLIBCXX_FWDREF(_Predicate) __pred,
+				_Distance __len,
 				_Pointer __buffer,
 				_Distance __buffer_size)
     {
@@ -1487,7 +1505,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 	  ++__result2;
 	  ++__first;
 	  for (; __first != __last; ++__first)
-	    if (__pred(__first))
+	    if (__pred(*__first))
 	      {
 		*__result1 = _GLIBCXX_MOVE(*__first);
 		++__result1;
@@ -1517,7 +1535,8 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 
       if (__right_len)
 	__right_split =
-	  std::__stable_partition_adaptive(__right_split, __last, __pred,
+	  std::__stable_partition_adaptive(__right_split, __last,
+					   _GLIBCXX_FORWARD(_Predicate, __pred),
 					   __right_len,
 					   __buffer, __buffer_size);
 
@@ -1527,7 +1546,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
   template<typename _ForwardIterator, typename _Predicate>
     _ForwardIterator
     __stable_partition(_ForwardIterator __first, _ForwardIterator __last,
-		       _Predicate __pred)
+		       _GLIBCXX_FWDREF(_Predicate) __pred)
     {
       __first = std::__find_if_not(__first, __last, __pred);
 
@@ -1542,7 +1561,8 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       _Temporary_buffer<_ForwardIterator, _ValueType>
 	__buf(__first, std::distance(__first, __last));
       return
-	std::__stable_partition_adaptive(__first, __last, __pred,
+	std::__stable_partition_adaptive(__first, __last,
+					 _GLIBCXX_FORWARD(_Predicate, __pred),
 					 _DistanceType(__buf.requested_size()),
 					 __buf.begin(),
 					 _DistanceType(__buf.size()));
@@ -1578,7 +1598,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_valid_range(__first, __last);
 
       return std::__stable_partition(__first, __last,
-				     __gnu_cxx::__ops::__pred_iter(__pred));
+				     _GLIBCXX_MOVE(__pred));
     }
 #endif // HOSTED
 
@@ -1590,11 +1610,12 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     void
     __heap_select(_RandomAccessIterator __first,
 		  _RandomAccessIterator __middle,
-		  _RandomAccessIterator __last, _Compare __comp)
+		  _RandomAccessIterator __last,
+		  _GLIBCXX_FWDREF(_Compare) __comp)
     {
       std::__make_heap(__first, __middle, __comp);
       for (_RandomAccessIterator __i = __middle; __i < __last; ++__i)
-	if (__comp(__i, __first))
+	if (__comp(*__i, *__first))
 	  std::__pop_heap(__first, __middle, __i, __comp);
     }
 
@@ -1607,7 +1628,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     __partial_sort_copy(_InputIterator __first, _InputIterator __last,
 			_RandomAccessIterator __result_first,
 			_RandomAccessIterator __result_last,
-			_Compare __comp)
+			_GLIBCXX_FWDREF(_Compare) __comp)
     {
       typedef typename iterator_traits<_InputIterator>::value_type
 	_InputValueType;
@@ -1627,14 +1648,15 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       std::__make_heap(__result_first, __result_real_last, __comp);
       while (__first != __last)
 	{
-	  if (__comp(__first, __result_first))
+	  if (__comp(*__first, *__result_first))
 	    std::__adjust_heap(__result_first, _DistanceType(0),
 			       _DistanceType(__result_real_last
 					     - __result_first),
 			       _InputValueType(*__first), __comp);
 	  ++__first;
 	}
-      std::__sort_heap(__result_first, __result_real_last, __comp);
+      std::__sort_heap(__result_first, __result_real_last,
+		       _GLIBCXX_FORWARD(_Compare, __comp));
       return __result_real_last;
     }
 
@@ -1683,9 +1705,11 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_irreflexive(__first, __last);
       __glibcxx_requires_valid_range(__result_first, __result_last);
 
+      __decltype(__gnu_cxx::__ops::__less(__first, __result_first)) __comp =
+	__gnu_cxx::__ops::__less(__first, __result_first);
       return std::__partial_sort_copy(__first, __last,
 				      __result_first, __result_last,
-				      __gnu_cxx::__ops::__iter_less_iter());
+				      __comp);
     }
 
   /**
@@ -1740,23 +1764,21 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 
       return std::__partial_sort_copy(__first, __last,
 				      __result_first, __result_last,
-				__gnu_cxx::__ops::__iter_comp_iter(__comp));
+				      _GLIBCXX_MOVE(__comp));
     }
 
   /// @cond undocumented
 
   /// This is a helper function for the sort routine.
-  template<typename _RandomAccessIterator, typename _Compare>
+  template<typename _RandomAccessIterator, typename _Val, typename _Compare>
     _GLIBCXX20_CONSTEXPR
     void
-    __unguarded_linear_insert(_RandomAccessIterator __last,
-			      _Compare __comp)
+    __unguarded_linear_insert(_RandomAccessIterator __last, _Val __val,
+			      _GLIBCXX_FWDREF(_Compare) __comp)
     {
-      typename iterator_traits<_RandomAccessIterator>::value_type
-	__val = _GLIBCXX_MOVE(*__last);
       _RandomAccessIterator __next = __last;
       --__next;
-      while (__comp(__val, __next))
+      while (__comp(__val, *__next))
 	{
 	  *__last = _GLIBCXX_MOVE(*__next);
 	  __last = __next;
@@ -1770,13 +1792,14 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     _GLIBCXX20_CONSTEXPR
     void
     __insertion_sort(_RandomAccessIterator __first,
-		     _RandomAccessIterator __last, _Compare __comp)
+		     _RandomAccessIterator __last,
+		     _GLIBCXX_FWDREF(_Compare) __comp)
     {
       if (__first == __last) return;
 
       for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i)
 	{
-	  if (__comp(__i, __first))
+	  if (__comp(*__i, *__first))
 	    {
 	      typename iterator_traits<_RandomAccessIterator>::value_type
 		__val = _GLIBCXX_MOVE(*__i);
@@ -1784,8 +1807,12 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 	      *__first = _GLIBCXX_MOVE(__val);
 	    }
 	  else
-	    std::__unguarded_linear_insert(__i,
-				__gnu_cxx::__ops::__val_comp_iter(__comp));
+	    {
+	      typename iterator_traits<_RandomAccessIterator>::value_type
+		__val = _GLIBCXX_MOVE(*__i);
+	      std::__unguarded_linear_insert(__i,
+					     _GLIBCXX_MOVE(__val), __comp);
+	    }
 	}
     }
 
@@ -1794,11 +1821,16 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     _GLIBCXX20_CONSTEXPR
     inline void
     __unguarded_insertion_sort(_RandomAccessIterator __first,
-			       _RandomAccessIterator __last, _Compare __comp)
+			       _RandomAccessIterator __last,
+			       _GLIBCXX_FWDREF(_Compare) __comp)
     {
       for (_RandomAccessIterator __i = __first; __i != __last; ++__i)
-	std::__unguarded_linear_insert(__i,
-				__gnu_cxx::__ops::__val_comp_iter(__comp));
+	{
+	  typename std::iterator_traits<_RandomAccessIterator>::value_type
+	    __val = _GLIBCXX_MOVE(*__i);
+	  std::__unguarded_linear_insert(__i,
+					 _GLIBCXX_MOVE(__val), __comp);
+	}
     }
 
   /**
@@ -1812,16 +1844,18 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     _GLIBCXX20_CONSTEXPR
     void
     __final_insertion_sort(_RandomAccessIterator __first,
-			   _RandomAccessIterator __last, _Compare __comp)
+			   _RandomAccessIterator __last,
+			   _GLIBCXX_FWDREF(_Compare) __comp)
     {
       if (__last - __first > int(_S_threshold))
 	{
 	  std::__insertion_sort(__first, __first + int(_S_threshold), __comp);
 	  std::__unguarded_insertion_sort(__first + int(_S_threshold), __last,
-					  __comp);
+					  _GLIBCXX_FORWARD(_Compare, __comp));
 	}
       else
-	std::__insertion_sort(__first, __last, __comp);
+	std::__insertion_sort(__first, __last,
+			      _GLIBCXX_FORWARD(_Compare, __comp));
     }
 
   /// This is a helper function...
@@ -1830,14 +1864,15 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     _RandomAccessIterator
     __unguarded_partition(_RandomAccessIterator __first,
 			  _RandomAccessIterator __last,
-			  _RandomAccessIterator __pivot, _Compare __comp)
+			  _RandomAccessIterator __pivot,
+			  _GLIBCXX_FWDREF(_Compare) __comp)
     {
       while (true)
 	{
-	  while (__comp(__first, __pivot))
+	  while (__comp(*__first, *__pivot))
 	    ++__first;
 	  --__last;
-	  while (__comp(__pivot, __last))
+	  while (__comp(*__pivot, *__last))
 	    --__last;
 	  if (!(__first < __last))
 	    return __first;
@@ -1851,12 +1886,14 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     _GLIBCXX20_CONSTEXPR
     inline _RandomAccessIterator
     __unguarded_partition_pivot(_RandomAccessIterator __first,
-				_RandomAccessIterator __last, _Compare __comp)
+				_RandomAccessIterator __last,
+				_GLIBCXX_FWDREF(_Compare) __comp)
     {
       _RandomAccessIterator __mid = __first + (__last - __first) / 2;
       std::__move_median_to_first(__first, __first + 1, __mid, __last - 1,
 				  __comp);
-      return std::__unguarded_partition(__first + 1, __last, __first, __comp);
+      return std::__unguarded_partition(__first + 1, __last, __first,
+					_GLIBCXX_FORWARD(_Compare, __comp));
     }
 
   template<typename _RandomAccessIterator, typename _Compare>
@@ -1865,10 +1902,10 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     __partial_sort(_RandomAccessIterator __first,
 		   _RandomAccessIterator __middle,
 		   _RandomAccessIterator __last,
-		   _Compare __comp)
+		   _GLIBCXX_FWDREF(_Compare) __comp)
     {
       std::__heap_select(__first, __middle, __last, __comp);
-      std::__sort_heap(__first, __middle, __comp);
+      std::__sort_heap(__first, __middle, _GLIBCXX_FORWARD(_Compare, __comp));
     }
 
   /// This is a helper function for the sort routine.
@@ -1877,13 +1914,14 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     void
     __introsort_loop(_RandomAccessIterator __first,
 		     _RandomAccessIterator __last,
-		     _Size __depth_limit, _Compare __comp)
+		     _Size __depth_limit, _GLIBCXX_FWDREF(_Compare) __comp)
     {
       while (__last - __first > int(_S_threshold))
 	{
 	  if (__depth_limit == 0)
 	    {
-	      std::__partial_sort(__first, __last, __last, __comp);
+	      std::__partial_sort(__first, __last, __last,
+				  _GLIBCXX_FORWARD(_Compare, __comp));
 	      return;
 	    }
 	  --__depth_limit;
@@ -1900,14 +1938,15 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     _GLIBCXX20_CONSTEXPR
     inline void
     __sort(_RandomAccessIterator __first, _RandomAccessIterator __last,
-	   _Compare __comp)
+	   _GLIBCXX_FWDREF(_Compare) __comp)
     {
       if (__first != __last)
 	{
 	  std::__introsort_loop(__first, __last,
 				std::__lg(__last - __first) * 2,
 				__comp);
-	  std::__final_insertion_sort(__first, __last, __comp);
+	  std::__final_insertion_sort(__first, __last,
+				      _GLIBCXX_FORWARD(_Compare, __comp));
 	}
     }
 
@@ -1916,13 +1955,14 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     void
     __introselect(_RandomAccessIterator __first, _RandomAccessIterator __nth,
 		  _RandomAccessIterator __last, _Size __depth_limit,
-		  _Compare __comp)
+		  _GLIBCXX_FWDREF(_Compare) __comp)
     {
       while (__last - __first > 3)
 	{
 	  if (__depth_limit == 0)
 	    {
-	      std::__heap_select(__first, __nth + 1, __last, __comp);
+	      std::__heap_select(__first, __nth + 1, __last,
+				 _GLIBCXX_FORWARD(_Compare, __comp));
 	      // Place the nth largest element in its final position.
 	      std::iter_swap(__first, __nth);
 	      return;
@@ -1935,7 +1975,8 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 	  else
 	    __last = __cut;
 	}
-      std::__insertion_sort(__first, __last, __comp);
+      std::__insertion_sort(__first, __last,
+			    _GLIBCXX_FORWARD(_Compare, __comp));
     }
 
   /// @endcond
@@ -1973,14 +2014,14 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 						__val, __comp);
 
       return std::__lower_bound(__first, __last, __val,
-				__gnu_cxx::__ops::__iter_comp_val(__comp));
+				_GLIBCXX_MOVE(__comp));
     }
 
   template<typename _ForwardIterator, typename _Tp, typename _Compare>
     _GLIBCXX20_CONSTEXPR
     _ForwardIterator
     __upper_bound(_ForwardIterator __first, _ForwardIterator __last,
-		  const _Tp& __val, _Compare __comp)
+		  const _Tp& __val, _GLIBCXX_FWDREF(_Compare) __comp)
     {
       typedef typename iterator_traits<_ForwardIterator>::difference_type
 	_DistanceType;
@@ -1992,7 +2033,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 	  _DistanceType __half = __len >> 1;
 	  _ForwardIterator __middle = __first;
 	  std::advance(__middle, __half);
-	  if (__comp(__val, __middle))
+	  if (__comp(__val, *__middle))
 	    __len = __half;
 	  else
 	    {
@@ -2027,8 +2068,9 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 	_Tp, typename iterator_traits<_ForwardIterator>::value_type>)
       __glibcxx_requires_partitioned_upper(__first, __last, __val);
 
-      return std::__upper_bound(__first, __last, __val,
-				__gnu_cxx::__ops::__val_less_iter());
+      __decltype(__gnu_cxx::__ops::__less_val(__first, __val)) __comp =
+	__gnu_cxx::__ops::__less_val(__first, __val);
+      return std::__upper_bound(__first, __last, __val, __comp);
     }
 
   /**
@@ -2059,17 +2101,14 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_partitioned_upper_pred(__first, __last,
 						__val, __comp);
 
-      return std::__upper_bound(__first, __last, __val,
-				__gnu_cxx::__ops::__val_comp_iter(__comp));
+      return std::__upper_bound(__first, __last, __val, _GLIBCXX_MOVE(__comp));
     }
 
-  template<typename _ForwardIterator, typename _Tp,
-	   typename _CompareItTp, typename _CompareTpIt>
+  template<typename _ForwardIterator, typename _Tp, typename _Comp>
     _GLIBCXX20_CONSTEXPR
     pair<_ForwardIterator, _ForwardIterator>
     __equal_range(_ForwardIterator __first, _ForwardIterator __last,
-		  const _Tp& __val,
-		  _CompareItTp __comp_it_val, _CompareTpIt __comp_val_it)
+		  const _Tp& __val, _GLIBCXX_FWDREF(_Comp) __comp)
     {
       typedef typename iterator_traits<_ForwardIterator>::difference_type
 	_DistanceType;
@@ -2081,21 +2120,22 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 	  _DistanceType __half = __len >> 1;
 	  _ForwardIterator __middle = __first;
 	  std::advance(__middle, __half);
-	  if (__comp_it_val(__middle, __val))
+	  if (__comp(*__middle, __val))
 	    {
 	      __first = __middle;
 	      ++__first;
 	      __len = __len - __half - 1;
 	    }
-	  else if (__comp_val_it(__val, __middle))
+	  else if (__comp(__val, *__middle))
 	    __len = __half;
 	  else
 	    {
 	      _ForwardIterator __left
-		= std::__lower_bound(__first, __middle, __val, __comp_it_val);
+		= std::__lower_bound(__first, __middle, __val, __comp);
 	      std::advance(__first, __len);
 	      _ForwardIterator __right
-		= std::__upper_bound(++__middle, __first, __val, __comp_val_it);
+		= std::__upper_bound(++__middle, __first, __val,
+				     _GLIBCXX_FORWARD(_Comp, __comp));
 	      return pair<_ForwardIterator, _ForwardIterator>(__left, __right);
 	    }
 	}
@@ -2134,9 +2174,9 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_partitioned_lower(__first, __last, __val);
       __glibcxx_requires_partitioned_upper(__first, __last, __val);
 
-      return std::__equal_range(__first, __last, __val,
-				__gnu_cxx::__ops::__iter_less_val(),
-				__gnu_cxx::__ops::__val_less_iter());
+      __decltype(__gnu_cxx::__ops::__less_val(__first, __val)) __comp =
+	__gnu_cxx::__ops::__less_val(__first, __val);
+      return std::__equal_range(__first, __last, __val, __comp);
     }
 
   /**
@@ -2173,9 +2213,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_partitioned_upper_pred(__first, __last,
 						__val, __comp);
 
-      return std::__equal_range(__first, __last, __val,
-				__gnu_cxx::__ops::__iter_comp_val(__comp),
-				__gnu_cxx::__ops::__val_comp_iter(__comp));
+      return std::__equal_range(__first, __last, __val, _GLIBCXX_MOVE(__comp));
     }
 
   /**
@@ -2203,9 +2241,10 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_partitioned_lower(__first, __last, __val);
       __glibcxx_requires_partitioned_upper(__first, __last, __val);
 
-      _ForwardIterator __i
-	= std::__lower_bound(__first, __last, __val,
-			     __gnu_cxx::__ops::__iter_less_val());
+      __decltype(__gnu_cxx::__ops::__less_val(__first, __val)) __comp =
+	__gnu_cxx::__ops::__less_val(__first, __val);
+      _ForwardIterator __i =
+	std::__lower_bound(__first, __last, __val, __comp);
       return __i != __last && !(__val < *__i);
     }
 
@@ -2240,8 +2279,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 						__val, __comp);
 
       _ForwardIterator __i
-	= std::__lower_bound(__first, __last, __val,
-			     __gnu_cxx::__ops::__iter_comp_val(__comp));
+	= std::__lower_bound(__first, __last, __val, __comp);
       return __i != __last && !bool(__comp(__val, *__i));
     }
 
@@ -2253,11 +2291,12 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     void
     __move_merge_adaptive(_InputIterator1 __first1, _InputIterator1 __last1,
 			  _InputIterator2 __first2, _InputIterator2 __last2,
-			  _OutputIterator __result, _Compare __comp)
+			  _OutputIterator __result,
+			  _GLIBCXX_FWDREF(_Compare) __comp)
     {
       while (__first1 != __last1 && __first2 != __last2)
 	{
-	  if (__comp(__first2, __first1))
+	  if (__comp(*__first2, *__first1))
 	    {
 	      *__result = _GLIBCXX_MOVE(*__first2);
 	      ++__first2;
@@ -2282,7 +2321,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 				   _BidirectionalIterator2 __first2,
 				   _BidirectionalIterator2 __last2,
 				   _BidirectionalIterator3 __result,
-				   _Compare __comp)
+				   _GLIBCXX_FWDREF(_Compare) __comp)
     {
       if (__first1 == __last1)
 	{
@@ -2296,7 +2335,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       --__last2;
       while (true)
 	{
-	  if (__comp(__last2, __last1))
+	  if (__comp(*__last2, *__last1))
 	    {
 	      *--__result = _GLIBCXX_MOVE(*__last1);
 	      if (__first1 == __last1)
@@ -2362,19 +2401,23 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 		     _BidirectionalIterator __middle,
 		     _BidirectionalIterator __last,
 		     _Distance __len1, _Distance __len2,
-		     _Pointer __buffer, _Compare __comp)
+		     _Pointer __buffer, _GLIBCXX_FWDREF(_Compare) __comp)
     {
+      __decltype(__gnu_cxx::__ops::__less(_GLIBCXX_FORWARD(_Compare, __comp),
+					  __first, __buffer)) __cmp
+	= __gnu_cxx::__ops::__less(_GLIBCXX_FORWARD(_Compare, __comp),
+				   __first, __buffer);
       if (__len1 <= __len2)
 	{
 	  _Pointer __buffer_end = _GLIBCXX_MOVE3(__first, __middle, __buffer);
 	  std::__move_merge_adaptive(__buffer, __buffer_end, __middle, __last,
-				     __first, __comp);
+				__first, _GLIBCXX_FORWARD(_Compare, __cmp));
 	}
       else
 	{
 	  _Pointer __buffer_end = _GLIBCXX_MOVE3(__middle, __last, __buffer);
 	  std::__move_merge_adaptive_backward(__first, __middle, __buffer,
-					      __buffer_end, __last, __comp);
+	    __buffer_end, __last, _GLIBCXX_FORWARD(_Compare, __cmp));
 	}
     }
 
@@ -2386,13 +2429,15 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 			    _BidirectionalIterator __last,
 			    _Distance __len1, _Distance __len2,
 			    _Pointer __buffer, _Distance __buffer_size,
-			    _Compare __comp)
+			    _GLIBCXX_FWDREF(_Compare) __comp)
     {
       if (__len1 <= __buffer_size || __len2 <= __buffer_size)
 	std::__merge_adaptive(__first, __middle, __last,
-			      __len1, __len2, __buffer, __comp);
+	  __len1, __len2, __buffer, _GLIBCXX_FORWARD(_Compare, __comp));
       else
 	{
+	  typedef typename
+	    std::iterator_traits<_BidirectionalIterator>::value_type _Val;
 	  _BidirectionalIterator __first_cut = __first;
 	  _BidirectionalIterator __second_cut = __middle;
 	  _Distance __len11 = 0;
@@ -2401,18 +2446,18 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 	    {
 	      __len11 = __len1 / 2;
 	      std::advance(__first_cut, __len11);
+	      const _Val& __val = *__first_cut;
 	      __second_cut
-		= std::__lower_bound(__middle, __last, *__first_cut,
-				     __gnu_cxx::__ops::__iter_comp_val(__comp));
+		= std::__lower_bound(__middle, __last, __val, __comp);
 	      __len22 = std::distance(__middle, __second_cut);
 	    }
 	  else
 	    {
 	      __len22 = __len2 / 2;
 	      std::advance(__second_cut, __len22);
+	      const _Val& __val = *__second_cut;
 	      __first_cut
-		= std::__upper_bound(__first, __middle, *__second_cut,
-				     __gnu_cxx::__ops::__val_comp_iter(__comp));
+		= std::__upper_bound(__first, __middle, __val, __comp);
 	      __len11 = std::distance(__first, __first_cut);
 	    }
 
@@ -2426,7 +2471,8 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 	  std::__merge_adaptive_resize(__new_middle, __second_cut, __last,
 				       _Distance(__len1 - __len11),
 				       _Distance(__len2 - __len22),
-				       __buffer, __buffer_size, __comp);
+				       __buffer, __buffer_size,
+				       _GLIBCXX_FORWARD(_Compare, __comp));
 	}
     }
 
@@ -2438,18 +2484,20 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 			   _BidirectionalIterator __middle,
 			   _BidirectionalIterator __last,
 			   _Distance __len1, _Distance __len2,
-			   _Compare __comp)
+			   _GLIBCXX_FWDREF(_Compare) __comp)
     {
       if (__len1 == 0 || __len2 == 0)
 	return;
 
       if (__len1 + __len2 == 2)
 	{
-	  if (__comp(__middle, __first))
+	  if (__comp(*__middle, *__first))
 	    std::iter_swap(__first, __middle);
 	  return;
 	}
 
+      typedef
+	typename std::iterator_traits<_BidirectionalIterator>::value_type _Val;
       _BidirectionalIterator __first_cut = __first;
       _BidirectionalIterator __second_cut = __middle;
       _Distance __len11 = 0;
@@ -2458,18 +2506,18 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 	{
 	  __len11 = __len1 / 2;
 	  std::advance(__first_cut, __len11);
+	  const _Val& __val = *__first_cut;
 	  __second_cut
-	    = std::__lower_bound(__middle, __last, *__first_cut,
-				 __gnu_cxx::__ops::__iter_comp_val(__comp));
+	    = std::__lower_bound(__middle, __last, __val, __comp);
 	  __len22 = std::distance(__middle, __second_cut);
 	}
       else
 	{
 	  __len22 = __len2 / 2;
 	  std::advance(__second_cut, __len22);
+	  const _Val& __val = *__second_cut;
 	  __first_cut
-	    = std::__upper_bound(__first, __middle, *__second_cut,
-				 __gnu_cxx::__ops::__val_comp_iter(__comp));
+	    = std::__upper_bound(__first, __middle, __val, __comp);
 	  __len11 = std::distance(__first, __first_cut);
 	}
 
@@ -2478,7 +2526,8 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       std::__merge_without_buffer(__first, __first_cut, __new_middle,
 				  __len11, __len22, __comp);
       std::__merge_without_buffer(__new_middle, __second_cut, __last,
-				  __len1 - __len11, __len2 - __len22, __comp);
+				  __len1 - __len11, __len2 - __len22,
+				  _GLIBCXX_FORWARD(_Compare, __comp));
     }
 
   template<typename _BidirectionalIterator, typename _Compare>
@@ -2486,7 +2535,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     __inplace_merge(_BidirectionalIterator __first,
 		    _BidirectionalIterator __middle,
 		    _BidirectionalIterator __last,
-		    _Compare __comp)
+		    _GLIBCXX_FWDREF(_Compare) __comp)
     {
       typedef typename iterator_traits<_BidirectionalIterator>::value_type
 	  _ValueType;
@@ -2507,17 +2556,21 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 
       if (__builtin_expect(__buf.size() == __buf.requested_size(), true))
 	std::__merge_adaptive
-	  (__first, __middle, __last, __len1, __len2, __buf.begin(), __comp);
+	  (__first, __middle, __last, __len1, __len2, __buf.begin(),
+	   _GLIBCXX_FORWARD(_Compare, __comp));
       else if (__builtin_expect(__buf.begin() == 0, false))
 	std::__merge_without_buffer
-	  (__first, __middle, __last, __len1, __len2, __comp);
+	  (__first, __middle, __last, __len1, __len2,
+	   _GLIBCXX_FORWARD(_Compare, __comp));
       else
 	std::__merge_adaptive_resize
 	  (__first, __middle, __last, __len1, __len2, __buf.begin(),
-	   _DistanceType(__buf.size()), __comp);
+	   _DistanceType(__buf.size()),
+	   _GLIBCXX_FORWARD(_Compare, __comp));
 #else
       std::__merge_without_buffer
-	(__first, __middle, __last, __len1, __len2, __comp);
+	(__first, __middle, __last, __len1, __len2,
+	 _GLIBCXX_FORWARD(_Compare, __comp));
 #endif
     }
 
@@ -2554,8 +2607,9 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_sorted(__middle, __last);
       __glibcxx_requires_irreflexive(__first, __last);
 
-      std::__inplace_merge(__first, __middle, __last,
-			   __gnu_cxx::__ops::__iter_less_iter());
+      __decltype(__gnu_cxx::__ops::__less(__first)) __comp =
+	__gnu_cxx::__ops::__less(__first);
+      std::__inplace_merge(__first, __middle, __last, __comp);
     }
 
   /**
@@ -2597,8 +2651,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_sorted_pred(__middle, __last, __comp);
       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 
-      std::__inplace_merge(__first, __middle, __last,
-			   __gnu_cxx::__ops::__iter_comp_iter(__comp));
+      std::__inplace_merge(__first, __middle, __last, _GLIBCXX_MOVE(__comp));
     }
 
 
@@ -2608,11 +2661,11 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     _OutputIterator
     __move_merge(_InputIterator __first1, _InputIterator __last1,
 		 _InputIterator __first2, _InputIterator __last2,
-		 _OutputIterator __result, _Compare __comp)
+		 _OutputIterator __result, _GLIBCXX_FWDREF(_Compare) __comp)
     {
       while (__first1 != __last1 && __first2 != __last2)
 	{
-	  if (__comp(__first2, __first1))
+	  if (__comp(*__first2, *__first1))
 	    {
 	      *__result = _GLIBCXX_MOVE(*__first2);
 	      ++__first2;
@@ -2635,7 +2688,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     __merge_sort_loop(_RandomAccessIterator1 __first,
 		      _RandomAccessIterator1 __last,
 		      _RandomAccessIterator2 __result, _Distance __step_size,
-		      _Compare __comp)
+		      _GLIBCXX_FWDREF(_Compare) __comp)
     {
       const _Distance __two_step = 2 * __step_size;
 
@@ -2650,7 +2703,8 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __step_size = std::min(_Distance(__last - __first), __step_size);
 
       std::__move_merge(__first, __first + __step_size,
-			__first + __step_size, __last, __result, __comp);
+			__first + __step_size, __last, __result,
+			_GLIBCXX_FORWARD(_Compare, __comp));
     }
 
   template<typename _RandomAccessIterator, typename _Distance,
@@ -2659,14 +2713,16 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     void
     __chunk_insertion_sort(_RandomAccessIterator __first,
 			   _RandomAccessIterator __last,
-			   _Distance __chunk_size, _Compare __comp)
+			   _Distance __chunk_size,
+			   _GLIBCXX_FWDREF(_Compare) __comp)
     {
       while (__last - __first >= __chunk_size)
 	{
 	  std::__insertion_sort(__first, __first + __chunk_size, __comp);
 	  __first += __chunk_size;
 	}
-      std::__insertion_sort(__first, __last, __comp);
+      std::__insertion_sort
+	(__first, __last, _GLIBCXX_FORWARD(_Compare, __comp));
     }
 
   enum { _S_chunk_size = 7 };
@@ -2675,7 +2731,8 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     void
     __merge_sort_with_buffer(_RandomAccessIterator __first,
 			     _RandomAccessIterator __last,
-			     _Pointer __buffer, _Compare __comp)
+			     _Pointer __buffer,
+			     _GLIBCXX_FWDREF(_Compare) __comp)
     {
       typedef typename iterator_traits<_RandomAccessIterator>::difference_type
 	_Distance;
@@ -2702,14 +2759,16 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     __stable_sort_adaptive(_RandomAccessIterator __first,
 			   _RandomAccessIterator __middle,
 			   _RandomAccessIterator __last,
-			   _Pointer __buffer, _Compare __comp)
+			   _Pointer __buffer, _GLIBCXX_FWDREF(_Compare) __comp)
     {
-      std::__merge_sort_with_buffer(__first, __middle, __buffer, __comp);
-      std::__merge_sort_with_buffer(__middle, __last, __buffer, __comp);
+      __decltype(__gnu_cxx::__ops::__less(__comp, __first, __buffer)) __cmp
+	= __gnu_cxx::__ops::__less(__comp, __first, __buffer);
+      std::__merge_sort_with_buffer(__first, __middle, __buffer, __cmp);
+      std::__merge_sort_with_buffer(__middle, __last, __buffer, __cmp);
 
       std::__merge_adaptive(__first, __middle, __last,
 			    __middle - __first, __last - __middle,
-			    __buffer, __comp);
+			    __buffer, _GLIBCXX_FORWARD(_Compare, __comp));
     }
 
   template<typename _RandomAccessIterator, typename _Pointer,
@@ -2718,7 +2777,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     __stable_sort_adaptive_resize(_RandomAccessIterator __first,
 				  _RandomAccessIterator __last,
 				  _Pointer __buffer, _Distance __buffer_size,
-				  _Compare __comp)
+				  _GLIBCXX_FWDREF(_Compare) __comp)
     {
       const _Distance __len = (__last - __first + 1) / 2;
       const _RandomAccessIterator __middle = __first + __len;
@@ -2732,22 +2791,24 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 				       _Distance(__middle - __first),
 				       _Distance(__last - __middle),
 				       __buffer, __buffer_size,
-				       __comp);
+				       _GLIBCXX_FORWARD(_Compare, __comp));
 	}
       else
 	std::__stable_sort_adaptive(__first, __middle, __last,
-				    __buffer, __comp);
+				__buffer, _GLIBCXX_FORWARD(_Compare, __comp));
     }
 
   /// This is a helper function for the stable sorting routines.
   template<typename _RandomAccessIterator, typename _Compare>
     void
     __inplace_stable_sort(_RandomAccessIterator __first,
-			  _RandomAccessIterator __last, _Compare __comp)
+			  _RandomAccessIterator __last,
+			  _GLIBCXX_FWDREF(_Compare) __comp)
     {
       if (__last - __first < 15)
 	{
-	  std::__insertion_sort(__first, __last, __comp);
+	  std::__insertion_sort
+	    (__first, __last, _GLIBCXX_FORWARD(_Compare, __comp));
 	  return;
 	}
       _RandomAccessIterator __middle = __first + (__last - __first) / 2;
@@ -2756,7 +2817,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       std::__merge_without_buffer(__first, __middle, __last,
 				  __middle - __first,
 				  __last - __middle,
-				  __comp);
+				  _GLIBCXX_FORWARD(_Compare, __comp));
     }
 
   // stable_sort
@@ -2772,13 +2833,13 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     bool
     __includes(_InputIterator1 __first1, _InputIterator1 __last1,
 	       _InputIterator2 __first2, _InputIterator2 __last2,
-	       _Compare __comp)
+	       _GLIBCXX_FWDREF(_Compare) __comp)
     {
       while (__first1 != __last1 && __first2 != __last2)
 	{
-	  if (__comp(__first2, __first1))
+	  if (__comp(*__first2, *__first1))
 	    return false;
-	  if (!__comp(__first1, __first2))
+	  if (!__comp(*__first1, *__first2))
 	    ++__first2;
 	  ++__first1;
 	}
@@ -2824,8 +2885,9 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_irreflexive2(__first1, __last1);
       __glibcxx_requires_irreflexive2(__first2, __last2);
 
-      return std::__includes(__first1, __last1, __first2, __last2,
-			     __gnu_cxx::__ops::__iter_less_iter());
+      __decltype(__gnu_cxx::__ops::__less(__first1, __first2)) __comp =
+	__gnu_cxx::__ops::__less(__first1, __first2);
+      return std::__includes(__first1, __last1, __first2, __last2, __comp);
     }
 
   /**
@@ -2872,7 +2934,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);
 
       return std::__includes(__first1, __last1, __first2, __last2,
-			     __gnu_cxx::__ops::__iter_comp_iter(__comp));
+			     _GLIBCXX_MOVE(__comp));
     }
 
   // nth_element
@@ -2889,7 +2951,8 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     _GLIBCXX20_CONSTEXPR
     bool
     __next_permutation(_BidirectionalIterator __first,
-		       _BidirectionalIterator __last, _Compare __comp)
+		       _BidirectionalIterator __last,
+		       _GLIBCXX_FWDREF(_Compare) __comp)
     {
       if (__first == __last)
 	return false;
@@ -2904,10 +2967,10 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 	{
 	  _BidirectionalIterator __ii = __i;
 	  --__i;
-	  if (__comp(__i, __ii))
+	  if (__comp(*__i, *__ii))
 	    {
 	      _BidirectionalIterator __j = __last;
-	      while (!__comp(__i, --__j))
+	      while (!__comp(*__i, *(--__j)))
 		{}
 	      std::iter_swap(__i, __j);
 	      std::__reverse(__ii, __last,
@@ -2949,8 +3012,9 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive(__first, __last);
 
-      return std::__next_permutation
-	(__first, __last, __gnu_cxx::__ops::__iter_less_iter());
+      __decltype(__gnu_cxx::__ops::__less(__first)) __comp =
+	__gnu_cxx::__ops::__less(__first);
+      return std::__next_permutation(__first, __last, __comp);
     }
 
   /**
@@ -2983,15 +3047,15 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 
-      return std::__next_permutation
-	(__first, __last, __gnu_cxx::__ops::__iter_comp_iter(__comp));
+      return std::__next_permutation(__first, __last, _GLIBCXX_MOVE(__comp));
     }
 
   template<typename _BidirectionalIterator, typename _Compare>
     _GLIBCXX20_CONSTEXPR
     bool
     __prev_permutation(_BidirectionalIterator __first,
-		       _BidirectionalIterator __last, _Compare __comp)
+		       _BidirectionalIterator __last,
+		       _GLIBCXX_FWDREF(_Compare) __comp)
     {
       if (__first == __last)
 	return false;
@@ -3006,10 +3070,10 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 	{
 	  _BidirectionalIterator __ii = __i;
 	  --__i;
-	  if (__comp(__ii, __i))
+	  if (__comp(*__ii, *__i))
 	    {
 	      _BidirectionalIterator __j = __last;
-	      while (!__comp(--__j, __i))
+	      while (!__comp(*(--__j), *__i))
 		{}
 	      std::iter_swap(__i, __j);
 	      std::__reverse(__ii, __last,
@@ -3052,8 +3116,9 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive(__first, __last);
 
-      return std::__prev_permutation(__first, __last,
-				     __gnu_cxx::__ops::__iter_less_iter());
+      __decltype(__gnu_cxx::__ops::__less(__first)) __comp =
+	__gnu_cxx::__ops::__less(__first);
+      return std::__prev_permutation(__first, __last, __comp);
     }
 
   /**
@@ -3086,8 +3151,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 
-      return std::__prev_permutation(__first, __last,
-				__gnu_cxx::__ops::__iter_comp_iter(__comp));
+      return std::__prev_permutation(__first, __last, _GLIBCXX_MOVE(__comp));
     }
 
   // replace
@@ -3099,10 +3163,11 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     _OutputIterator
     __replace_copy_if(_InputIterator __first, _InputIterator __last,
 		      _OutputIterator __result,
-		      _Predicate __pred, const _Tp& __new_value)
+		      _GLIBCXX_FWDREF(_Predicate) __pred,
+		      const _Tp& __new_value)
     {
       for (; __first != __last; ++__first, (void)++__result)
-	if (__pred(__first))
+	if (__pred(*__first))
 	  *__result = __new_value;
 	else
 	  *__result = *__first;
@@ -3138,9 +3203,10 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 	    typename iterator_traits<_InputIterator>::value_type, _Tp>)
       __glibcxx_requires_valid_range(__first, __last);
 
+      __decltype(__gnu_cxx::__ops::__equal_val(__first, __old_value)) __pred =
+	__gnu_cxx::__ops::__equal_val(__first, __old_value);
       return std::__replace_copy_if(__first, __last, __result,
-			__gnu_cxx::__ops::__iter_equals_val(__old_value),
-					      __new_value);
+				    __pred, __new_value);
     }
 
   /**
@@ -3175,8 +3241,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_valid_range(__first, __last);
 
       return std::__replace_copy_if(__first, __last, __result,
-				__gnu_cxx::__ops::__pred_iter(__pred),
-					      __new_value);
+				    _GLIBCXX_MOVE(__pred), __new_value);
     }
 
 #if __cplusplus >= 201103L
@@ -3207,20 +3272,22 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     inline bool
     is_sorted(_ForwardIterator __first, _ForwardIterator __last,
 	      _Compare __comp)
-    { return std::is_sorted_until(__first, __last, __comp) == __last; }
+    {
+      return std::is_sorted_until(__first, __last, std::move(__comp)) == __last;
+    }
 
   template<typename _ForwardIterator, typename _Compare>
     _GLIBCXX20_CONSTEXPR
     _ForwardIterator
     __is_sorted_until(_ForwardIterator __first, _ForwardIterator __last,
-		      _Compare __comp)
+		      _Compare&& __comp)
     {
       if (__first == __last)
 	return __last;
 
       _ForwardIterator __next = __first;
       for (++__next; __next != __last; __first = __next, (void)++__next)
-	if (__comp(__next, __first))
+	if (__comp(*__next, *__first))
 	  return __next;
       return __next;
     }
@@ -3246,7 +3313,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_irreflexive(__first, __last);
 
       return std::__is_sorted_until(__first, __last,
-				    __gnu_cxx::__ops::__iter_less_iter());
+				    __gnu_cxx::__ops::__less());
     }
 
   /**
@@ -3272,8 +3339,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 
-      return std::__is_sorted_until(__first, __last,
-				    __gnu_cxx::__ops::__iter_comp_iter(__comp));
+      return std::__is_sorted_until(__first, __last, std::move(__comp));
     }
 
   /**
@@ -3318,7 +3384,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     _GLIBCXX14_CONSTEXPR
     pair<_ForwardIterator, _ForwardIterator>
     __minmax_element(_ForwardIterator __first, _ForwardIterator __last,
-		     _Compare __comp)
+		     _Compare&& __comp)
     {
       _ForwardIterator __next = __first;
       if (__first == __last
@@ -3326,7 +3392,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 	return std::make_pair(__first, __first);
 
       _ForwardIterator __min{}, __max{};
-      if (__comp(__next, __first))
+      if (__comp(*__next, *__first))
 	{
 	  __min = __next;
 	  __max = __first;
@@ -3345,25 +3411,25 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 	  __next = __first;
 	  if (++__next == __last)
 	    {
-	      if (__comp(__first, __min))
+	      if (__comp(*__first, *__min))
 		__min = __first;
-	      else if (!__comp(__first, __max))
+	      else if (!__comp(*__first, *__max))
 		__max = __first;
 	      break;
 	    }
 
-	  if (__comp(__next, __first))
+	  if (__comp(*__next, *__first))
 	    {
-	      if (__comp(__next, __min))
+	      if (__comp(*__next, *__min))
 		__min = __next;
-	      if (!__comp(__first, __max))
+	      if (!__comp(*__first, *__max))
 		__max = __first;
 	    }
 	  else
 	    {
-	      if (__comp(__first, __min))
+	      if (__comp(*__first, *__min))
 		__min = __first;
-	      if (!__comp(__next, __max))
+	      if (!__comp(*__next, *__max))
 		__max = __next;
 	    }
 
@@ -3398,7 +3464,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_irreflexive(__first, __last);
 
       return std::__minmax_element(__first, __last,
-				   __gnu_cxx::__ops::__iter_less_iter());
+				   __gnu_cxx::__ops::__less());
     }
 
   /**
@@ -3427,8 +3493,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 
-      return std::__minmax_element(__first, __last,
-				   __gnu_cxx::__ops::__iter_comp_iter(__comp));
+      return std::__minmax_element(__first, __last, std::move(__comp));
     }
 
   template<typename _Tp>
@@ -3439,7 +3504,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_irreflexive(__l.begin(), __l.end());
       pair<const _Tp*, const _Tp*> __p =
 	std::__minmax_element(__l.begin(), __l.end(),
-			      __gnu_cxx::__ops::__iter_less_iter());
+			      __gnu_cxx::__ops::__less());
       return std::make_pair(*__p.first, *__p.second);
     }
 
@@ -3450,8 +3515,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     {
       __glibcxx_requires_irreflexive_pred(__l.begin(), __l.end(), __comp);
       pair<const _Tp*, const _Tp*> __p =
-	std::__minmax_element(__l.begin(), __l.end(),
-			      __gnu_cxx::__ops::__iter_comp_iter(__comp));
+	std::__minmax_element(__l.begin(), __l.end(), std::move(__comp));
       return std::make_pair(*__p.first, *__p.second);
     }
 
@@ -3485,7 +3549,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_valid_range(__first1, __last1);
 
       return std::__is_permutation(__first1, __last1, __first2,
-				   __gnu_cxx::__ops::__iter_comp_iter(__pred));
+				   std::move(__pred));
     }
 
 #if __cplusplus > 201103L
@@ -3495,7 +3559,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
     bool
     __is_permutation(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
 		     _ForwardIterator2 __first2, _ForwardIterator2 __last2,
-		     _BinaryPredicate __pred)
+		     _BinaryPredicate&& __pred)
     {
       using _Cat1
 	= typename iterator_traits<_ForwardIterator1>::iterator_category;
@@ -3516,7 +3580,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       // have the same elements in the same order.
       for (; __first1 != __last1 && __first2 != __last2;
 	  ++__first1, (void)++__first2)
-	if (!__pred(__first1, __first2))
+	if (!__pred(*__first1, *__first2))
 	  break;
 
       if (__ra_iters)
@@ -3537,14 +3601,14 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       for (_ForwardIterator1 __scan = __first1; __scan != __last1; ++__scan)
 	{
 	  if (__scan != std::__find_if(__first1, __scan,
-			__gnu_cxx::__ops::__iter_comp_iter(__pred, __scan)))
+		__gnu_cxx::__ops::__equal_ite(__pred, __first1, __scan)))
 	    continue; // We've seen this one before.
 
 	  auto __matches = std::__count_if(__first2, __last2,
-		__gnu_cxx::__ops::__iter_comp_iter(__pred, __scan));
+	    __gnu_cxx::__ops::__equal_ite(__pred, __first2, __scan));
 	  if (0 == __matches
 	      || std::__count_if(__scan, __last1,
-			__gnu_cxx::__ops::__iter_comp_iter(__pred, __scan))
+		   __gnu_cxx::__ops::__equal_ite(__pred, __first1, __scan))
 	      != __matches)
 	    return false;
 	}
@@ -3575,7 +3639,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 
       return
 	std::__is_permutation(__first1, __last1, __first2, __last2,
-			      __gnu_cxx::__ops::__iter_equal_to_iter());
+			      __gnu_cxx::__ops::__equal_to());
     }
 
   /**
@@ -3604,7 +3668,7 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
       __glibcxx_requires_valid_range(__first2, __last2);
 
       return std::__is_permutation(__first1, __last1, __first2, __last2,
-				   __gnu_cxx::__ops::__iter_comp_iter(__pred));
+				   std::move(__pred));
     }
 #endif // C++14
 
@@ -3875,8 +3939,9 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
 	  }
 #endif
 
-      return std::__find_if(__first, __last,
-			    __gnu_cxx::__ops::__iter_equals_val(__val));
+      __decltype(__gnu_cxx::__ops::__equal_val(__first, __val)) __comp =
+	__gnu_cxx::__ops::__equal_val(__first, __val);
+      return std::__find_if(__first, __last, __comp);
     }
 
   /**
@@ -3901,8 +3966,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
 	      typename iterator_traits<_InputIterator>::value_type>)
       __glibcxx_requires_valid_range(__first, __last);
 
-      return std::__find_if(__first, __last,
-			    __gnu_cxx::__ops::__pred_iter(__pred));
+      return std::__find_if(__first, __last, _GLIBCXX_MOVE(__pred));
     }
 
   /**
@@ -4006,8 +4070,9 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
 	    typename iterator_traits<_ForwardIterator>::value_type>)
       __glibcxx_requires_valid_range(__first, __last);
 
-      return std::__adjacent_find(__first, __last,
-				  __gnu_cxx::__ops::__iter_equal_to_iter());
+      __decltype(__gnu_cxx::__ops::__equal_to(__first)) __comp =
+	__gnu_cxx::__ops::__equal_to(__first);
+      return std::__adjacent_find(__first, __last, __comp);
     }
 
   /**
@@ -4035,7 +4100,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__first, __last);
 
       return std::__adjacent_find(__first, __last,
-			__gnu_cxx::__ops::__iter_comp_iter(__binary_pred));
+				  _GLIBCXX_MOVE(__binary_pred));
     }
 
   /**
@@ -4058,8 +4123,9 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
 	    typename iterator_traits<_InputIterator>::value_type, _Tp>)
       __glibcxx_requires_valid_range(__first, __last);
 
-      return std::__count_if(__first, __last,
-			     __gnu_cxx::__ops::__iter_equals_val(__value));
+      __decltype(__gnu_cxx::__ops::__equal_val(__first, __value)) __comp =
+	__gnu_cxx::__ops::__equal_val(__first, __value);
+      return std::__count_if(__first, __last, __comp);
     }
 
   /**
@@ -4082,8 +4148,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
 	    typename iterator_traits<_InputIterator>::value_type>)
       __glibcxx_requires_valid_range(__first, __last);
 
-      return std::__count_if(__first, __last,
-			     __gnu_cxx::__ops::__pred_iter(__pred));
+      return std::__count_if(__first, __last, _GLIBCXX_MOVE(__pred));
     }
 
   /**
@@ -4127,8 +4192,9 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__first1, __last1);
       __glibcxx_requires_valid_range(__first2, __last2);
 
-      return std::__search(__first1, __last1, __first2, __last2,
-			   __gnu_cxx::__ops::__iter_equal_to_iter());
+      __decltype(__gnu_cxx::__ops::__equal_to(__first1, __first2)) __comp =
+	__gnu_cxx::__ops::__equal_to(__first1, __first2);
+      return std::__search(__first1, __last1, __first2, __last2, __comp);
     }
 
   /**
@@ -4158,8 +4224,9 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
 	    typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
       __glibcxx_requires_valid_range(__first, __last);
 
-      return std::__search_n(__first, __last, __count,
-			     __gnu_cxx::__ops::__iter_equals_val(__val));
+      __decltype(__gnu_cxx::__ops::__equal_val(__first, __val)) __comp =
+	__gnu_cxx::__ops::__equal_val(__first, __val);
+      return std::__search_n(__first, __last, __count, __comp);
     }
 
 
@@ -4194,8 +4261,12 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
 	    typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
       __glibcxx_requires_valid_range(__first, __last);
 
+      __decltype(__gnu_cxx::__ops::__comp_val
+		 (_GLIBCXX_MOVE(__binary_pred), __first, __val)) __unry_pred =
+	__gnu_cxx::__ops::__comp_val(_GLIBCXX_MOVE(__binary_pred),
+				     __first, __val);
       return std::__search_n(__first, __last, __count,
-		__gnu_cxx::__ops::__iter_comp_val(__binary_pred, __val));
+			     _GLIBCXX_MOVE(__unry_pred));
     }
 
 #if __cplusplus >= 201703L
@@ -4451,8 +4522,11 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
 
       if (__first == __last)
 	return __result;
+
+      __decltype(__gnu_cxx::__ops::__equal_to(__first)) __comp =
+	__gnu_cxx::__ops::__equal_to(__first);
       return std::__unique_copy(__first, __last, __result,
-				__gnu_cxx::__ops::__iter_equal_to_iter(),
+				__comp,
 				std::__iterator_category(__first),
 				std::__iterator_category(__result));
     }
@@ -4492,7 +4566,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       if (__first == __last)
 	return __result;
       return std::__unique_copy(__first, __last, __result,
-			__gnu_cxx::__ops::__iter_comp_iter(__binary_pred),
+				_GLIBCXX_MOVE(__binary_pred),
 				std::__iterator_category(__first),
 				std::__iterator_category(__result));
     }
@@ -4632,7 +4706,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
 	    typename iterator_traits<_ForwardIterator>::value_type>)
       __glibcxx_requires_valid_range(__first, __last);
 
-      return std::__partition(__first, __last, __pred,
+      return std::__partition(__first, __last, _GLIBCXX_MOVE(__pred),
 			      std::__iterator_category(__first));
     }
 
@@ -4670,8 +4744,9 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__middle, __last);
       __glibcxx_requires_irreflexive(__first, __last);
 
-      std::__partial_sort(__first, __middle, __last,
-			  __gnu_cxx::__ops::__iter_less_iter());
+      __decltype(__gnu_cxx::__ops::__less(__first)) __comp =
+	__gnu_cxx::__ops::__less(__first);
+      std::__partial_sort(__first, __middle, __last, __comp);
     }
 
   /**
@@ -4711,8 +4786,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__middle, __last);
       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 
-      std::__partial_sort(__first, __middle, __last,
-			  __gnu_cxx::__ops::__iter_comp_iter(__comp));
+      std::__partial_sort(__first, __middle, __last, _GLIBCXX_MOVE(__comp));
     }
 
   /**
@@ -4748,9 +4822,11 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       if (__first == __last || __nth == __last)
 	return;
 
+      __decltype(__gnu_cxx::__ops::__less(__first)) __comp =
+	__gnu_cxx::__ops::__less(__first);
       std::__introselect(__first, __nth, __last,
 			 std::__lg(__last - __first) * 2,
-			 __gnu_cxx::__ops::__iter_less_iter());
+			 __comp);
     }
 
   /**
@@ -4791,7 +4867,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
 
       std::__introselect(__first, __nth, __last,
 			 std::__lg(__last - __first) * 2,
-			 __gnu_cxx::__ops::__iter_comp_iter(__comp));
+			 _GLIBCXX_MOVE(__comp));
     }
 
   /**
@@ -4821,7 +4897,9 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive(__first, __last);
 
-      std::__sort(__first, __last, __gnu_cxx::__ops::__iter_less_iter());
+      __decltype(__gnu_cxx::__ops::__less(__first)) __comp =
+	__gnu_cxx::__ops::__less(__first);
+      std::__sort(__first, __last, __comp);
     }
 
   /**
@@ -4854,7 +4932,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 
-      std::__sort(__first, __last, __gnu_cxx::__ops::__iter_comp_iter(__comp));
+      std::__sort(__first, __last, _GLIBCXX_MOVE(__comp));
     }
 
   template<typename _InputIterator1, typename _InputIterator2,
@@ -4863,11 +4941,11 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
     _OutputIterator
     __merge(_InputIterator1 __first1, _InputIterator1 __last1,
 	    _InputIterator2 __first2, _InputIterator2 __last2,
-	    _OutputIterator __result, _Compare __comp)
+	    _OutputIterator __result, _GLIBCXX_FWDREF(_Compare) __comp)
     {
       while (__first1 != __last1 && __first2 != __last2)
 	{
-	  if (__comp(__first2, __first1))
+	  if (__comp(*__first2, *__first1))
 	    {
 	      *__result = *__first2;
 	      ++__first2;
@@ -4925,9 +5003,10 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_irreflexive2(__first1, __last1);
       __glibcxx_requires_irreflexive2(__first2, __last2);
 
+      __decltype(__gnu_cxx::__ops::__less(__first1, __first2)) __comp =
+	__gnu_cxx::__ops::__less(__first1, __first2);
       return _GLIBCXX_STD_A::__merge(__first1, __last1,
-				     __first2, __last2, __result,
-				     __gnu_cxx::__ops::__iter_less_iter());
+				     __first2, __last2, __result, __comp);
     }
 
   /**
@@ -4977,14 +5056,14 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);
 
       return _GLIBCXX_STD_A::__merge(__first1, __last1,
-				__first2, __last2, __result,
-				__gnu_cxx::__ops::__iter_comp_iter(__comp));
+				     __first2, __last2, __result,
+				     _GLIBCXX_MOVE(__comp));
     }
 
   template<typename _RandomAccessIterator, typename _Compare>
     inline void
     __stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last,
-		  _Compare __comp)
+		  _GLIBCXX_FWDREF(_Compare) __comp)
     {
       typedef typename iterator_traits<_RandomAccessIterator>::value_type
 	_ValueType;
@@ -5003,14 +5082,18 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       if (__builtin_expect(__buf.requested_size() == __buf.size(), true))
 	std::__stable_sort_adaptive(__first,
 				    __first + _DistanceType(__buf.size()),
-				    __last, __buf.begin(), __comp);
+				    __last, __buf.begin(),
+				    _GLIBCXX_FORWARD(_Compare, __comp));
       else if (__builtin_expect(__buf.begin() == 0, false))
-	std::__inplace_stable_sort(__first, __last, __comp);
+	std::__inplace_stable_sort(__first, __last,
+				   _GLIBCXX_FORWARD(_Compare, __comp));
       else
 	std::__stable_sort_adaptive_resize(__first, __last, __buf.begin(),
-					   _DistanceType(__buf.size()), __comp);
+					   _DistanceType(__buf.size()),
+					   _GLIBCXX_FORWARD(_Compare, __comp));
 #else
-      std::__inplace_stable_sort(__first, __last, __comp);
+      std::__inplace_stable_sort
+	(__first, __last, _GLIBCXX_FORWARD(_Compare, __comp));
 #endif
     }
 
@@ -5043,8 +5126,9 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive(__first, __last);
 
-      _GLIBCXX_STD_A::__stable_sort(__first, __last,
-				    __gnu_cxx::__ops::__iter_less_iter());
+      __decltype(__gnu_cxx::__ops::__less(__first)) __comp =
+	__gnu_cxx::__ops::__less(__first);
+      _GLIBCXX_STD_A::__stable_sort(__first, __last, __comp);
     }
 
   /**
@@ -5079,8 +5163,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 
-      _GLIBCXX_STD_A::__stable_sort(__first, __last,
-				    __gnu_cxx::__ops::__iter_comp_iter(__comp));
+      _GLIBCXX_STD_A::__stable_sort(__first, __last, _GLIBCXX_MOVE(__comp));
     }
 
   template<typename _InputIterator1, typename _InputIterator2,
@@ -5090,16 +5173,16 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
     _OutputIterator
     __set_union(_InputIterator1 __first1, _InputIterator1 __last1,
 		_InputIterator2 __first2, _InputIterator2 __last2,
-		_OutputIterator __result, _Compare __comp)
+		_OutputIterator __result, _GLIBCXX_FWDREF(_Compare) __comp)
     {
       while (__first1 != __last1 && __first2 != __last2)
 	{
-	  if (__comp(__first1, __first2))
+	  if (__comp(*__first1, *__first2))
 	    {
 	      *__result = *__first1;
 	      ++__first1;
 	    }
-	  else if (__comp(__first2, __first1))
+	  else if (__comp(*__first2, *__first1))
 	    {
 	      *__result = *__first2;
 	      ++__first2;
@@ -5161,9 +5244,10 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_irreflexive2(__first1, __last1);
       __glibcxx_requires_irreflexive2(__first2, __last2);
 
+      __decltype(__gnu_cxx::__ops::__less(__first1, __first2)) __comp =
+	__gnu_cxx::__ops::__less(__first1, __first2);
       return _GLIBCXX_STD_A::__set_union(__first1, __last1,
-				__first2, __last2, __result,
-				__gnu_cxx::__ops::__iter_less_iter());
+					 __first2, __last2, __result, __comp);
     }
 
   /**
@@ -5213,8 +5297,8 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);
 
       return _GLIBCXX_STD_A::__set_union(__first1, __last1,
-				__first2, __last2, __result,
-				__gnu_cxx::__ops::__iter_comp_iter(__comp));
+					 __first2, __last2, __result,
+					 _GLIBCXX_MOVE(__comp));
     }
 
   template<typename _InputIterator1, typename _InputIterator2,
@@ -5224,12 +5308,13 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
     _OutputIterator
     __set_intersection(_InputIterator1 __first1, _InputIterator1 __last1,
 		       _InputIterator2 __first2, _InputIterator2 __last2,
-		       _OutputIterator __result, _Compare __comp)
+		       _OutputIterator __result,
+		       _GLIBCXX_FWDREF(_Compare) __comp)
     {
       while (__first1 != __last1 && __first2 != __last2)
-	if (__comp(__first1, __first2))
+	if (__comp(*__first1, *__first2))
 	  ++__first1;
-	else if (__comp(__first2, __first1))
+	else if (__comp(*__first2, *__first1))
 	  ++__first2;
 	else
 	  {
@@ -5283,9 +5368,10 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_irreflexive2(__first1, __last1);
       __glibcxx_requires_irreflexive2(__first2, __last2);
 
+      __decltype(__gnu_cxx::__ops::__less(__first1, __first2)) __comp =
+	__gnu_cxx::__ops::__less(__first1, __first2);
       return _GLIBCXX_STD_A::__set_intersection(__first1, __last1,
-				     __first2, __last2, __result,
-				     __gnu_cxx::__ops::__iter_less_iter());
+					__first2, __last2, __result, __comp);
     }
 
   /**
@@ -5334,8 +5420,8 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);
 
       return _GLIBCXX_STD_A::__set_intersection(__first1, __last1,
-				__first2, __last2, __result,
-				__gnu_cxx::__ops::__iter_comp_iter(__comp));
+						__first2, __last2, __result,
+						_GLIBCXX_MOVE(__comp));
     }
 
   template<typename _InputIterator1, typename _InputIterator2,
@@ -5345,16 +5431,16 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
     _OutputIterator
     __set_difference(_InputIterator1 __first1, _InputIterator1 __last1,
 		     _InputIterator2 __first2, _InputIterator2 __last2,
-		     _OutputIterator __result, _Compare __comp)
+		     _OutputIterator __result, _GLIBCXX_FWDREF(_Compare) __comp)
     {
       while (__first1 != __last1 && __first2 != __last2)
-	if (__comp(__first1, __first2))
+	if (__comp(*__first1, *__first2))
 	  {
 	    *__result = *__first1;
 	    ++__first1;
 	    ++__result;
 	  }
-	else if (__comp(__first2, __first1))
+	else if (__comp(*__first2, *__first1))
 	  ++__first2;
 	else
 	  {
@@ -5408,9 +5494,10 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_irreflexive2(__first1, __last1);
       __glibcxx_requires_irreflexive2(__first2, __last2);
 
+      __decltype(__gnu_cxx::__ops::__less(__first1, __first2)) __comp =
+	__gnu_cxx::__ops::__less(__first1, __first2);
       return _GLIBCXX_STD_A::__set_difference(__first1, __last1,
-				   __first2, __last2, __result,
-				   __gnu_cxx::__ops::__iter_less_iter());
+					__first2, __last2, __result, __comp);
     }
 
   /**
@@ -5461,8 +5548,8 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);
 
       return _GLIBCXX_STD_A::__set_difference(__first1, __last1,
-				   __first2, __last2, __result,
-				   __gnu_cxx::__ops::__iter_comp_iter(__comp));
+					      __first2, __last2, __result,
+					      _GLIBCXX_MOVE(__comp));
     }
 
   template<typename _InputIterator1, typename _InputIterator2,
@@ -5475,16 +5562,16 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
 			       _InputIterator2 __first2,
 			       _InputIterator2 __last2,
 			       _OutputIterator __result,
-			       _Compare __comp)
+			       _GLIBCXX_FWDREF(_Compare) __comp)
     {
       while (__first1 != __last1 && __first2 != __last2)
-	if (__comp(__first1, __first2))
+	if (__comp(*__first1, *__first2))
 	  {
 	    *__result = *__first1;
 	    ++__first1;
 	    ++__result;
 	  }
-	else if (__comp(__first2, __first1))
+	else if (__comp(*__first2, *__first1))
 	  {
 	    *__result = *__first2;
 	    ++__first2;
@@ -5543,9 +5630,10 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_irreflexive2(__first1, __last1);
       __glibcxx_requires_irreflexive2(__first2, __last2);
 
+      __decltype(__gnu_cxx::__ops::__less(__first1, __first2)) __comp =
+	__gnu_cxx::__ops::__less(__first1, __first2);
       return _GLIBCXX_STD_A::__set_symmetric_difference(__first1, __last1,
-					__first2, __last2, __result,
-					__gnu_cxx::__ops::__iter_less_iter());
+					__first2, __last2, __result, __comp);
     }
 
   /**
@@ -5597,21 +5685,21 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_irreflexive_pred2(__first2, __last2, __comp);
 
       return _GLIBCXX_STD_A::__set_symmetric_difference(__first1, __last1,
-				__first2, __last2, __result,
-				__gnu_cxx::__ops::__iter_comp_iter(__comp));
+						__first2, __last2, __result,
+							_GLIBCXX_MOVE(__comp));
     }
 
   template<typename _ForwardIterator, typename _Compare>
     _GLIBCXX14_CONSTEXPR
     _ForwardIterator
     __min_element(_ForwardIterator __first, _ForwardIterator __last,
-		  _Compare __comp)
+		  _GLIBCXX_FWDREF(_Compare) __comp)
     {
       if (__first == __last)
 	return __first;
       _ForwardIterator __result = __first;
       while (++__first != __last)
-	if (__comp(__first, __result))
+	if (__comp(*__first, *__result))
 	  __result = __first;
       return __result;
     }
@@ -5635,8 +5723,9 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive(__first, __last);
 
-      return _GLIBCXX_STD_A::__min_element(__first, __last,
-				__gnu_cxx::__ops::__iter_less_iter());
+      __decltype(__gnu_cxx::__ops::__less(__first)) __comp =
+	__gnu_cxx::__ops::__less(__first);
+      return _GLIBCXX_STD_A::__min_element(__first, __last, __comp);
     }
 
   /**
@@ -5663,19 +5752,19 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 
       return _GLIBCXX_STD_A::__min_element(__first, __last,
-				__gnu_cxx::__ops::__iter_comp_iter(__comp));
+					   _GLIBCXX_MOVE(__comp));
     }
 
   template<typename _ForwardIterator, typename _Compare>
     _GLIBCXX14_CONSTEXPR
     _ForwardIterator
     __max_element(_ForwardIterator __first, _ForwardIterator __last,
-		  _Compare __comp)
+		  _GLIBCXX_FWDREF(_Compare) __comp)
     {
       if (__first == __last) return __first;
       _ForwardIterator __result = __first;
       while (++__first != __last)
-	if (__comp(__result, __first))
+	if (__comp(*__result, *__first))
 	  __result = __first;
       return __result;
     }
@@ -5699,8 +5788,9 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive(__first, __last);
 
-      return _GLIBCXX_STD_A::__max_element(__first, __last,
-				__gnu_cxx::__ops::__iter_less_iter());
+      __decltype(__gnu_cxx::__ops::__less(__first)) __comp =
+	__gnu_cxx::__ops::__less(__first);
+      return _GLIBCXX_STD_A::__max_element(__first, __last, __comp);
     }
 
   /**
@@ -5727,7 +5817,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 
       return _GLIBCXX_STD_A::__max_element(__first, __last,
-				__gnu_cxx::__ops::__iter_comp_iter(__comp));
+					   _GLIBCXX_MOVE(__comp));
     }
 
 #if __cplusplus >= 201103L
@@ -5739,7 +5829,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
     {
       __glibcxx_requires_irreflexive(__l.begin(), __l.end());
       return *_GLIBCXX_STD_A::__min_element(__l.begin(), __l.end(),
-	  __gnu_cxx::__ops::__iter_less_iter());
+					    __gnu_cxx::__ops::__less());
     }
 
   template<typename _Tp, typename _Compare>
@@ -5749,7 +5839,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
     {
       __glibcxx_requires_irreflexive_pred(__l.begin(), __l.end(), __comp);
       return *_GLIBCXX_STD_A::__min_element(__l.begin(), __l.end(),
-	  __gnu_cxx::__ops::__iter_comp_iter(__comp));
+					    std::move(__comp));
     }
 
   template<typename _Tp>
@@ -5759,7 +5849,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
     {
       __glibcxx_requires_irreflexive(__l.begin(), __l.end());
       return *_GLIBCXX_STD_A::__max_element(__l.begin(), __l.end(),
-	  __gnu_cxx::__ops::__iter_less_iter());
+					    __gnu_cxx::__ops::__less());
     }
 
   template<typename _Tp, typename _Compare>
@@ -5769,7 +5859,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
     {
       __glibcxx_requires_irreflexive_pred(__l.begin(), __l.end(), __comp);
       return *_GLIBCXX_STD_A::__max_element(__l.begin(), __l.end(),
-	  __gnu_cxx::__ops::__iter_comp_iter(__comp));
+					    std::move(__comp));
     }
 #endif // C++11
 
diff --git a/libstdc++-v3/include/bits/stl_algobase.h b/libstdc++-v3/include/bits/stl_algobase.h
index 9e92211c124..4496b9a1c46 100644
--- a/libstdc++-v3/include/bits/stl_algobase.h
+++ b/libstdc++-v3/include/bits/stl_algobase.h
@@ -1348,7 +1348,7 @@ _GLIBCXX_END_NAMESPACE_CONTAINER
     bool
     __lexicographical_compare_impl(_II1 __first1, _II1 __last1,
 				   _II2 __first2, _II2 __last2,
-				   _Compare __comp)
+				   _GLIBCXX_FWDREF(_Compare) __comp)
     {
       typedef typename iterator_traits<_II1>::iterator_category _Category1;
       typedef typename iterator_traits<_II2>::iterator_category _Category2;
@@ -1358,9 +1358,9 @@ _GLIBCXX_END_NAMESPACE_CONTAINER
       for (; __first1 != __last1 && __rai_type::__cnd2(__first2, __last2);
 	   ++__first1, (void)++__first2)
 	{
-	  if (__comp(__first1, __first2))
+	  if (__comp(*__first1, *__first2))
 	    return true;
-	  if (__comp(__first2, __first1))
+	  if (__comp(*__first2, *__first1))
 	    return false;
 	}
       return __first1 == __last1 && __first2 != __last2;
@@ -1374,10 +1374,11 @@ _GLIBCXX_END_NAMESPACE_CONTAINER
 	static bool
 	__lc(_II1 __first1, _II1 __last1, _II2 __first2, _II2 __last2)
 	{
-	  using __gnu_cxx::__ops::__iter_less_iter;
+	  __decltype(__gnu_cxx::__ops::__less(__first1, __first2)) __comp =
+	    __gnu_cxx::__ops::__less(__first1, __first2);
 	  return std::__lexicographical_compare_impl(__first1, __last1,
 						     __first2, __last2,
-						     __iter_less_iter());
+						     __comp);
 	}
 
       template<typename _II1, typename _II2>
@@ -1521,7 +1522,7 @@ _GLIBCXX_END_NAMESPACE_CONTAINER
     _GLIBCXX20_CONSTEXPR
     _ForwardIterator
     __lower_bound(_ForwardIterator __first, _ForwardIterator __last,
-		  const _Tp& __val, _Compare __comp)
+		  const _Tp& __val, _GLIBCXX_FWDREF(_Compare) __comp)
     {
       typedef typename iterator_traits<_ForwardIterator>::difference_type
 	_DistanceType;
@@ -1533,7 +1534,7 @@ _GLIBCXX_END_NAMESPACE_CONTAINER
 	  _DistanceType __half = __len >> 1;
 	  _ForwardIterator __middle = __first;
 	  std::advance(__middle, __half);
-	  if (__comp(__middle, __val))
+	  if (__comp(*__middle, __val))
 	    {
 	      __first = __middle;
 	      ++__first;
@@ -1568,8 +1569,9 @@ _GLIBCXX_END_NAMESPACE_CONTAINER
 	    typename iterator_traits<_ForwardIterator>::value_type, _Tp>)
       __glibcxx_requires_partitioned_lower(__first, __last, __val);
 
-      return std::__lower_bound(__first, __last, __val,
-				__gnu_cxx::__ops::__iter_less_val());
+      __decltype(__gnu_cxx::__ops::__less_val(__first, __val)) __comp =
+	__gnu_cxx::__ops::__less_val(__first, __val);
+      return std::__lower_bound(__first, __last, __val, __comp);
     }
 
   /// This is a helper function for the sort routines and for random.tcc.
@@ -1688,7 +1690,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
     _GLIBCXX20_CONSTEXPR
     inline bool
     __equal4(_II1 __first1, _II1 __last1, _II2 __first2, _II2 __last2,
-	     _BinaryPredicate __binary_pred)
+	     _BinaryPredicate&& __binary_pred)
     {
       using _RATag = random_access_iterator_tag;
       using _Cat1 = typename iterator_traits<_II1>::iterator_category;
@@ -1701,7 +1703,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
 	  if (__d1 != __d2)
 	    return false;
 	  return _GLIBCXX_STD_A::equal(__first1, __last1, __first2,
-				       __binary_pred);
+	     std::forward<_BinaryPredicate>(__binary_pred));
 	}
 
       for (; __first1 != __last1 && __first2 != __last2;
@@ -1772,7 +1774,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__first2, __last2);
 
       return _GLIBCXX_STD_A::__equal4(__first1, __last1, __first2, __last2,
-				      __binary_pred);
+				      std::move(__binary_pred));
     }
 #endif // __glibcxx_robust_nonmodifying_seq_ops
 
@@ -1839,8 +1841,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__first2, __last2);
 
       return std::__lexicographical_compare_impl
-	(__first1, __last1, __first2, __last2,
-	 __gnu_cxx::__ops::__iter_comp_iter(__comp));
+	(__first1, __last1, __first2, __last2, _GLIBCXX_MOVE(__comp));
     }
 
 #if __cpp_lib_three_way_comparison
@@ -1946,9 +1947,10 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
     _GLIBCXX20_CONSTEXPR
     pair<_InputIterator1, _InputIterator2>
     __mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
-	       _InputIterator2 __first2, _BinaryPredicate __binary_pred)
+	       _InputIterator2 __first2,
+	       _GLIBCXX_FWDREF(_BinaryPredicate) __binary_pred)
     {
-      while (__first1 != __last1 && __binary_pred(__first1, __first2))
+      while (__first1 != __last1 && __binary_pred(*__first1, *__first2))
 	{
 	  ++__first1;
 	  ++__first2;
@@ -1983,8 +1985,9 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
 	    typename iterator_traits<_InputIterator2>::value_type>)
       __glibcxx_requires_valid_range(__first1, __last1);
 
-      return _GLIBCXX_STD_A::__mismatch(__first1, __last1, __first2,
-			     __gnu_cxx::__ops::__iter_equal_to_iter());
+      __decltype(__gnu_cxx::__ops::__equal_to(__first1, __first2)) __comp =
+	__gnu_cxx::__ops::__equal_to(__first1, __first2);
+      return _GLIBCXX_STD_A::__mismatch(__first1, __last1, __first2, __comp);
     }
 
   /**
@@ -2016,7 +2019,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__first1, __last1);
 
       return _GLIBCXX_STD_A::__mismatch(__first1, __last1, __first2,
-	__gnu_cxx::__ops::__iter_comp_iter(__binary_pred));
+					_GLIBCXX_MOVE(__binary_pred));
     }
 
 #if __glibcxx_robust_nonmodifying_seq_ops // C++ >= 14
@@ -2026,10 +2029,10 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
     pair<_InputIterator1, _InputIterator2>
     __mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
 	       _InputIterator2 __first2, _InputIterator2 __last2,
-	       _BinaryPredicate __binary_pred)
+	       _BinaryPredicate&& __binary_pred)
     {
       while (__first1 != __last1 && __first2 != __last2
-	     && __binary_pred(__first1, __first2))
+	     && __binary_pred(*__first1, *__first2))
 	{
 	  ++__first1;
 	  ++__first2;
@@ -2067,7 +2070,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__first2, __last2);
 
       return _GLIBCXX_STD_A::__mismatch(__first1, __last1, __first2, __last2,
-			     __gnu_cxx::__ops::__iter_equal_to_iter());
+			__gnu_cxx::__ops::__equal_to(__first1, __first2));
     }
 
   /**
@@ -2102,7 +2105,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__first2, __last2);
 
       return _GLIBCXX_STD_A::__mismatch(__first1, __last1, __first2, __last2,
-			     __gnu_cxx::__ops::__iter_comp_iter(__binary_pred));
+					_GLIBCXX_MOVE(__binary_pred));
     }
 #endif
 
@@ -2112,10 +2115,11 @@ _GLIBCXX_END_NAMESPACE_ALGO
   template<typename _Iterator, typename _Predicate>
     _GLIBCXX20_CONSTEXPR
     inline _Iterator
-    __find_if(_Iterator __first, _Iterator __last, _Predicate __pred)
+    __find_if(_Iterator __first, _Iterator __last,
+	      _GLIBCXX_FWDREF(_Predicate) __pred)
     {
 #pragma GCC unroll 4
-      while (__first != __last && !__pred(__first))
+      while (__first != __last && !__pred(*__first))
 	++__first;
       return __first;
     }
@@ -2123,11 +2127,12 @@ _GLIBCXX_END_NAMESPACE_ALGO
   template<typename _InputIterator, typename _Predicate>
     _GLIBCXX20_CONSTEXPR
     typename iterator_traits<_InputIterator>::difference_type
-    __count_if(_InputIterator __first, _InputIterator __last, _Predicate __pred)
+    __count_if(_InputIterator __first, _InputIterator __last,
+	       _GLIBCXX_FWDREF(_Predicate) __pred)
     {
       typename iterator_traits<_InputIterator>::difference_type __n = 0;
       for (; __first != __last; ++__first)
-	if (__pred(__first))
+	if (__pred(*__first))
 	  ++__n;
       return __n;
     }
@@ -2136,7 +2141,7 @@ _GLIBCXX_END_NAMESPACE_ALGO
     _GLIBCXX20_CONSTEXPR
     _ForwardIterator
     __remove_if(_ForwardIterator __first, _ForwardIterator __last,
-		_Predicate __pred)
+		_GLIBCXX_FWDREF(_Predicate) __pred)
     {
       __first = std::__find_if(__first, __last, __pred);
       if (__first == __last)
@@ -2144,7 +2149,7 @@ _GLIBCXX_END_NAMESPACE_ALGO
       _ForwardIterator __result = __first;
       ++__first;
       for (; __first != __last; ++__first)
-	if (!__pred(__first))
+	if (!__pred(*__first))
 	  {
 	    *__result = _GLIBCXX_MOVE(*__first);
 	    ++__result;
@@ -2158,7 +2163,7 @@ _GLIBCXX_END_NAMESPACE_ALGO
     _ForwardIterator1
     __search(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
 	     _ForwardIterator2 __first2, _ForwardIterator2 __last2,
-	     _BinaryPredicate  __predicate)
+	     _GLIBCXX_FWDREF(_BinaryPredicate)  __predicate)
     {
       // Test for empty ranges
       if (__first1 == __last1 || __first2 == __last2)
@@ -2167,18 +2172,25 @@ _GLIBCXX_END_NAMESPACE_ALGO
       // Test for a pattern of length 1.
       _ForwardIterator2 __p1(__first2);
       if (++__p1 == __last2)
-	return std::__find_if(__first1, __last1,
-		__gnu_cxx::__ops::__iter_comp_iter(__predicate, __first2));
+	{
+	  __decltype(__gnu_cxx::__ops::__equal_ite
+		     (_GLIBCXX_FORWARD(_BinaryPredicate, __predicate),
+		      __first1, __first2)) __cmp =
+	    __gnu_cxx::__ops::__equal_ite
+	    (_GLIBCXX_FORWARD(_BinaryPredicate, __predicate),
+	     __first1, __first2);
+	  return std::__find_if(__first1, __last1, _GLIBCXX_MOVE(__cmp));
+	}
 
       // General case.
       _ForwardIterator1 __current = __first1;
 
+      __decltype(__gnu_cxx::__ops::__equal_ite(__predicate, __first1, __first2))
+	__unry_pred = __gnu_cxx::__ops::__equal_ite(__predicate,
+						    __first1, __first2);
       for (;;)
 	{
-	  __first1 =
-	    std::__find_if(__first1, __last1,
-		__gnu_cxx::__ops::__iter_comp_iter(__predicate, __first2));
-
+	  __first1 = std::__find_if(__first1, __last1, __unry_pred);
 	  if (__first1 == __last1)
 	    return __last1;
 
@@ -2187,7 +2199,7 @@ _GLIBCXX_END_NAMESPACE_ALGO
 	  if (++__current == __last1)
 	    return __last1;
 
-	  while (__predicate(__current, __p))
+	  while (__predicate(*__current, *__p))
 	    {
 	      if (++__p == __last2)
 		return __first1;
@@ -2210,7 +2222,7 @@ _GLIBCXX_END_NAMESPACE_ALGO
       // Efficiently compare identical prefixes:  O(N) if sequences
       // have the same elements in the same order.
       for (; __first1 != __last1; ++__first1, (void)++__first2)
-	if (!__pred(__first1, __first2))
+	if (!__pred(*__first1, *__first2))
 	  break;
 
       if (__first1 == __last1)
@@ -2223,15 +2235,15 @@ _GLIBCXX_END_NAMESPACE_ALGO
       for (_ForwardIterator1 __scan = __first1; __scan != __last1; ++__scan)
 	{
 	  if (__scan != std::__find_if(__first1, __scan,
-			  __gnu_cxx::__ops::__iter_comp_iter(__pred, __scan)))
+		__gnu_cxx::__ops::__equal_ite(__pred, __first1, __scan)))
 	    continue; // We've seen this one before.
 
 	  auto __matches
 	    = std::__count_if(__first2, __last2,
-			__gnu_cxx::__ops::__iter_comp_iter(__pred, __scan));
+		__gnu_cxx::__ops::__equal_ite(__pred, __first2, __scan));
 	  if (0 == __matches ||
 	      std::__count_if(__scan, __last1,
-			__gnu_cxx::__ops::__iter_comp_iter(__pred, __scan))
+		__gnu_cxx::__ops::__equal_ite(__pred, __first1, __scan))
 	      != __matches)
 	    return false;
 	}
@@ -2265,7 +2277,7 @@ _GLIBCXX_END_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__first1, __last1);
 
       return std::__is_permutation(__first1, __last1, __first2,
-				   __gnu_cxx::__ops::__iter_equal_to_iter());
+				   __gnu_cxx::__ops::__equal_to());
     }
 #endif // C++11
 
@@ -2310,7 +2322,7 @@ _GLIBCXX_BEGIN_NAMESPACE_ALGO
       __glibcxx_requires_valid_range(__first2, __last2);
 
       return std::__search(__first1, __last1, __first2, __last2,
-			   __gnu_cxx::__ops::__iter_comp_iter(__predicate));
+			   _GLIBCXX_MOVE(__predicate));
     }
 
 _GLIBCXX_END_NAMESPACE_ALGO
diff --git a/libstdc++-v3/include/bits/stl_heap.h b/libstdc++-v3/include/bits/stl_heap.h
index 9c1214a2b21..d499d15f517 100644
--- a/libstdc++-v3/include/bits/stl_heap.h
+++ b/libstdc++-v3/include/bits/stl_heap.h
@@ -74,12 +74,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     _GLIBCXX20_CONSTEXPR
     _Distance
     __is_heap_until(_RandomAccessIterator __first, _Distance __n,
-		    _Compare& __comp)
+		    _GLIBCXX_FWDREF(_Compare) __comp)
     {
       _Distance __parent = 0;
       for (_Distance __child = 1; __child < __n; ++__child)
 	{
-	  if (__comp(__first + __parent, __first + __child))
+	  if (__comp(__first[__parent], __first[__child]))
 	    return __child;
 	  if ((__child & 1) == 0)
 	    ++__parent;
@@ -94,7 +94,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     inline bool
     __is_heap(_RandomAccessIterator __first, _Distance __n)
     {
-      __gnu_cxx::__ops::_Iter_less_iter __comp;
+      __decltype(__gnu_cxx::__ops::__less(__first)) __comp =
+	__gnu_cxx::__ops::__less(__first);
       return std::__is_heap_until(__first, __n, __comp) == __n;
     }
 
@@ -102,11 +103,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	   typename _Distance>
     _GLIBCXX20_CONSTEXPR
     inline bool
-    __is_heap(_RandomAccessIterator __first, _Compare __comp, _Distance __n)
+    __is_heap(_RandomAccessIterator __first, _GLIBCXX_FWDREF(_Compare) __comp,
+	      _Distance __n)
     {
-      typedef __decltype(__comp) _Cmp;
-      __gnu_cxx::__ops::_Iter_comp_iter<_Cmp> __cmp(_GLIBCXX_MOVE(__comp));
-      return std::__is_heap_until(__first, __n, __cmp) == __n;
+      return std::__is_heap_until
+	(__first, __n, _GLIBCXX_FORWARD(_Compare, __comp)) == __n;
     }
 
   template<typename _RandomAccessIterator>
@@ -119,9 +120,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     _GLIBCXX20_CONSTEXPR
     inline bool
     __is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
-	      _Compare __comp)
+	      _GLIBCXX_FWDREF(_Compare) __comp)
     {
-      return std::__is_heap(__first, _GLIBCXX_MOVE(__comp),
+      return std::__is_heap(__first, _GLIBCXX_FORWARD(_Compare, __comp),
 			    std::distance(__first, __last));
     }
 
@@ -133,17 +134,22 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     _GLIBCXX20_CONSTEXPR
     void
     __push_heap(_RandomAccessIterator __first,
-		_Distance __holeIndex, _Distance __topIndex, _Tp __value,
-		_Compare& __comp)
+		_Distance __holeIndex, _Distance __topIndex,
+#if __cplusplus >= 201103L
+		_Tp&& __value,
+#else
+		_Tp __value,
+#endif
+		_GLIBCXX_FWDREF(_Compare) __comp)
     {
       _Distance __parent = (__holeIndex - 1) / 2;
-      while (__holeIndex > __topIndex && __comp(__first + __parent, __value))
+      while (__holeIndex > __topIndex && __comp(__first[__parent], __value))
 	{
 	  *(__first + __holeIndex) = _GLIBCXX_MOVE(*(__first + __parent));
 	  __holeIndex = __parent;
 	  __parent = (__holeIndex - 1) / 2;
 	}
-      *(__first + __holeIndex) = _GLIBCXX_MOVE(__value);
+      *(__first + __holeIndex) = _GLIBCXX_FORWARD(_Tp, __value);
     }
 
   /**
@@ -174,8 +180,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       __glibcxx_requires_irreflexive(__first, __last);
       __glibcxx_requires_heap(__first, __last - 1);
 
-      __gnu_cxx::__ops::_Iter_less_val __comp;
       _ValueType __value = _GLIBCXX_MOVE(*(__last - 1));
+      __decltype(__gnu_cxx::__ops::__less_val(__first, __value)) __comp =
+	__gnu_cxx::__ops::__less_val(__first, __value);
       std::__push_heap(__first, _DistanceType((__last - __first) - 1),
 		       _DistanceType(0), _GLIBCXX_MOVE(__value), __comp);
     }
@@ -210,11 +217,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
       __glibcxx_requires_heap_pred(__first, __last - 1, __comp);
 
-      __decltype(__gnu_cxx::__ops::__iter_comp_val(_GLIBCXX_MOVE(__comp)))
-	__cmp(_GLIBCXX_MOVE(__comp));
       _ValueType __value = _GLIBCXX_MOVE(*(__last - 1));
       std::__push_heap(__first, _DistanceType((__last - __first) - 1),
-		       _DistanceType(0), _GLIBCXX_MOVE(__value), __cmp);
+		       _DistanceType(0), _GLIBCXX_MOVE(__value),
+		       _GLIBCXX_MOVE(__comp));
     }
 
   template<typename _RandomAccessIterator, typename _Distance,
@@ -222,15 +228,21 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     _GLIBCXX20_CONSTEXPR
     void
     __adjust_heap(_RandomAccessIterator __first, _Distance __holeIndex,
-		  _Distance __len, _Tp __value, _Compare __comp)
+		  _Distance __len,
+#if __cplusplus >= 201103L
+		  _Tp&& __value,
+#else
+		  _Tp __value,
+#endif
+		  _GLIBCXX_FWDREF(_Compare) __comp)
     {
       const _Distance __topIndex = __holeIndex;
       _Distance __secondChild = __holeIndex;
       while (__secondChild < (__len - 1) / 2)
 	{
 	  __secondChild = 2 * (__secondChild + 1);
-	  if (__comp(__first + __secondChild,
-		     __first + (__secondChild - 1)))
+	  if (__comp(__first[__secondChild],
+		     __first[__secondChild - 1]))
 	    __secondChild--;
 	  *(__first + __holeIndex) = _GLIBCXX_MOVE(*(__first + __secondChild));
 	  __holeIndex = __secondChild;
@@ -242,17 +254,20 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 						     + (__secondChild - 1)));
 	  __holeIndex = __secondChild - 1;
 	}
-      __decltype(__gnu_cxx::__ops::__iter_comp_val(_GLIBCXX_MOVE(__comp)))
-	__cmp(_GLIBCXX_MOVE(__comp));
+      __decltype(__gnu_cxx::__ops::__less_val(_GLIBCXX_FORWARD(_Compare, __comp),
+					      __first, __value)) __cmp =
+	__gnu_cxx::__ops::__less_val(_GLIBCXX_FORWARD(_Compare, __comp),
+				     __first, __value);
       std::__push_heap(__first, __holeIndex, __topIndex,
-		       _GLIBCXX_MOVE(__value), __cmp);
+		       _GLIBCXX_FORWARD(_Tp, __value),
+		       _GLIBCXX_FORWARD(_Compare, __cmp));
     }
 
   template<typename _RandomAccessIterator, typename _Compare>
     _GLIBCXX20_CONSTEXPR
     inline void
     __pop_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
-	       _RandomAccessIterator __result, _Compare& __comp)
+	       _RandomAccessIterator __result, _GLIBCXX_FWDREF(_Compare) __comp)
     {
       typedef typename iterator_traits<_RandomAccessIterator>::value_type
 	_ValueType;
@@ -263,7 +278,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       *__result = _GLIBCXX_MOVE(*__first);
       std::__adjust_heap(__first, _DistanceType(0),
 			 _DistanceType(__last - __first),
-			 _GLIBCXX_MOVE(__value), __comp);
+		_GLIBCXX_MOVE(__value), _GLIBCXX_FORWARD(_Compare, __comp));
     }
 
   /**
@@ -295,7 +310,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       if (__last - __first > 1)
 	{
 	  --__last;
-	  __gnu_cxx::__ops::_Iter_less_iter __comp;
+	  __decltype(__gnu_cxx::__ops::__less(__first)) __comp =
+	    __gnu_cxx::__ops::__less(__first);
 	  std::__pop_heap(__first, __last, __last, __comp);
 	}
     }
@@ -327,10 +343,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 
       if (__last - __first > 1)
 	{
-	  typedef __decltype(__comp) _Cmp;
-	  __gnu_cxx::__ops::_Iter_comp_iter<_Cmp> __cmp(_GLIBCXX_MOVE(__comp));
 	  --__last;
-	  std::__pop_heap(__first, __last, __last, __cmp);
+	  std::__pop_heap(__first, __last, __last, _GLIBCXX_MOVE(__comp));
 	}
     }
 
@@ -338,7 +352,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     _GLIBCXX20_CONSTEXPR
     void
     __make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
-		_Compare& __comp)
+		_GLIBCXX_FWDREF(_Compare) __comp)
     {
       typedef typename iterator_traits<_RandomAccessIterator>::value_type
 	  _ValueType;
@@ -382,7 +396,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive(__first, __last);
 
-      __gnu_cxx::__ops::_Iter_less_iter __comp;
+      __decltype(__gnu_cxx::__ops::__less(__first)) __comp =
+	__gnu_cxx::__ops::__less(__first);
       std::__make_heap(__first, __last, __comp);
     }
 
@@ -408,16 +423,14 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 
-      typedef __decltype(__comp) _Cmp;
-      __gnu_cxx::__ops::_Iter_comp_iter<_Cmp> __cmp(_GLIBCXX_MOVE(__comp));
-      std::__make_heap(__first, __last, __cmp);
+      std::__make_heap(__first, __last, _GLIBCXX_MOVE(__comp));
     }
 
   template<typename _RandomAccessIterator, typename _Compare>
     _GLIBCXX20_CONSTEXPR
     void
     __sort_heap(_RandomAccessIterator __first, _RandomAccessIterator __last,
-		_Compare& __comp)
+		_GLIBCXX_FWDREF(_Compare) __comp)
     {
       while (__last - __first > 1)
 	{
@@ -448,7 +461,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       __glibcxx_requires_irreflexive(__first, __last);
       __glibcxx_requires_heap(__first, __last);
 
-      __gnu_cxx::__ops::_Iter_less_iter __comp;
+      __decltype(__gnu_cxx::__ops::__less(__first)) __comp =
+	__gnu_cxx::__ops::__less(__first);
       std::__sort_heap(__first, __last, __comp);
     }
 
@@ -475,9 +489,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
       __glibcxx_requires_heap_pred(__first, __last, __comp);
 
-      typedef __decltype(__comp) _Cmp;
-      __gnu_cxx::__ops::_Iter_comp_iter<_Cmp> __cmp(_GLIBCXX_MOVE(__comp));
-      std::__sort_heap(__first, __last, __cmp);
+      std::__sort_heap(__first, __last, _GLIBCXX_MOVE(__comp));
     }
 
 #if __cplusplus >= 201103L
@@ -504,9 +516,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive(__first, __last);
 
-      __gnu_cxx::__ops::_Iter_less_iter __comp;
       return __first + 
-	std::__is_heap_until(__first, std::distance(__first, __last), __comp);
+	std::__is_heap_until(__first, std::distance(__first, __last),
+			     __gnu_cxx::__ops::__less());
     }
 
   /**
@@ -532,10 +544,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 
-      typedef __decltype(__comp) _Cmp;
-      __gnu_cxx::__ops::_Iter_comp_iter<_Cmp> __cmp(_GLIBCXX_MOVE(__comp));
       return __first
-	+ std::__is_heap_until(__first, std::distance(__first, __last), __cmp);
+	+ std::__is_heap_until(__first, std::distance(__first, __last),
+			       std::move(__comp));
     }
 
   /**
@@ -572,11 +583,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       __glibcxx_requires_irreflexive_pred(__first, __last, __comp);
 
       const auto __dist = std::distance(__first, __last);
-      typedef __decltype(__comp) _Cmp;
-      __gnu_cxx::__ops::_Iter_comp_iter<_Cmp> __cmp(_GLIBCXX_MOVE(__comp));
-      return std::__is_heap_until(__first, __dist, __cmp) == __dist;
+      return std::__is_heap_until(__first, __dist,
+				  std::move(__comp)) == __dist;
     }
-#endif
+#endif // C++11
 
 _GLIBCXX_END_NAMESPACE_VERSION
 } // namespace
diff --git a/libstdc++-v3/include/bits/stl_tree.h b/libstdc++-v3/include/bits/stl_tree.h
index bc27e191e8b..8338a4d7acb 100644
--- a/libstdc++-v3/include/bits/stl_tree.h
+++ b/libstdc++-v3/include/bits/stl_tree.h
@@ -463,7 +463,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 
 	template<typename _Arg>
 	  _Link_type
-	  operator()(_GLIBCXX_FWDREF(_Arg) __arg)
+	  operator()(_GLIBCXX_FWDCREF(_Arg) __arg)
 	  {
 	    _Link_type __node = static_cast<_Link_type>(_M_extract());
 	    if (__node)
@@ -525,7 +525,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 
 	template<typename _Arg>
 	  _Link_type
-	  operator()(_GLIBCXX_FWDREF(_Arg) __arg) const
+	  operator()(_GLIBCXX_FWDCREF(_Arg) __arg) const
 	  { return _M_t._M_create_node(_GLIBCXX_FORWARD(_Arg, __arg)); }
 
       private:
diff --git a/libstdc++-v3/include/std/deque b/libstdc++-v3/include/std/deque
index 33396d180c8..924db7f37bc 100644
--- a/libstdc++-v3/include/std/deque
+++ b/libstdc++-v3/include/std/deque
@@ -66,7 +66,7 @@
 #include <bits/stl_construct.h>
 #include <bits/stl_uninitialized.h>
 #include <bits/stl_deque.h>
-#include <bits/refwrap.h>
+#include <bits/move.h>
 #include <bits/range_access.h>
 #include <bits/deque.tcc>
 
@@ -103,12 +103,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     inline typename deque<_Tp, _Alloc>::size_type
     erase_if(deque<_Tp, _Alloc>& __cont, _Predicate __pred)
     {
-      using namespace __gnu_cxx;
       _GLIBCXX_STD_C::deque<_Tp, _Alloc>& __ucont = __cont;
       const auto __osz = __cont.size();
       const auto __end = __ucont.end();
       auto __removed = std::__remove_if(__ucont.begin(), __end,
-					__ops::__pred_iter(std::ref(__pred)));
+					std::move(__pred));
       if (__removed != __end)
 	{
 	  __cont.erase(__niter_wrap(__cont.begin(), __removed),
@@ -129,7 +128,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       const auto __osz = __cont.size();
       const auto __end = __ucont.end();
       auto __removed = std::__remove_if(__ucont.begin(), __end,
-					__ops::__iter_equals_val(__value));
+					__ops::__equal_val(__value));
       if (__removed != __end)
 	{
 	  __cont.erase(__niter_wrap(__cont.begin(), __removed),
diff --git a/libstdc++-v3/include/std/functional b/libstdc++-v3/include/std/functional
index 743defc3cb8..e830d1e28d0 100644
--- a/libstdc++-v3/include/std/functional
+++ b/libstdc++-v3/include/std/functional
@@ -60,6 +60,9 @@
 #if _GLIBCXX_HOSTED
 # include <bits/std_function.h>	// std::function
 #endif
+#if __cplusplus >= 201402L
+# include <bits/predefined_ops.h> // std::_Not_fn
+#endif
 #if __cplusplus >= 201703L
 # if _GLIBCXX_HOSTED
 #  include <unordered_map>
@@ -1119,57 +1122,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 #endif // __cpp_lib_bind_back
 
 #if __cplusplus >= 201402L
-  /// Generalized negator.
-  template<typename _Fn>
-    class _Not_fn
-    {
-      template<typename _Fn2, typename... _Args>
-	using __inv_res_t = typename __invoke_result<_Fn2, _Args...>::type;
-
-      template<typename _Tp>
-	static decltype(!std::declval<_Tp>())
-	_S_not() noexcept(noexcept(!std::declval<_Tp>()));
-
-    public:
-      template<typename _Fn2>
-	constexpr
-	_Not_fn(_Fn2&& __fn, int)
-	: _M_fn(std::forward<_Fn2>(__fn)) { }
-
-      _Not_fn(const _Not_fn& __fn) = default;
-      _Not_fn(_Not_fn&& __fn) = default;
-      ~_Not_fn() = default;
-
-      // Macro to define operator() with given cv-qualifiers ref-qualifiers,
-      // forwarding _M_fn and the function arguments with the same qualifiers,
-      // and deducing the return type and exception-specification.
-#define _GLIBCXX_NOT_FN_CALL_OP( _QUALS )				\
-      template<typename... _Args,					\
-	       typename = enable_if_t<__is_invocable<_Fn _QUALS, _Args...>::value>> \
-	_GLIBCXX20_CONSTEXPR						\
-	decltype(_S_not<__inv_res_t<_Fn _QUALS, _Args...>>())		\
-	operator()(_Args&&... __args) _QUALS				\
-	noexcept(__is_nothrow_invocable<_Fn _QUALS, _Args...>::value	\
-	    && noexcept(_S_not<__inv_res_t<_Fn _QUALS, _Args...>>()))	\
-	{								\
-	  return !std::__invoke(std::forward< _Fn _QUALS >(_M_fn),	\
-				std::forward<_Args>(__args)...);	\
-	}								\
-									\
-      template<typename... _Args,					\
-	       typename = enable_if_t<!__is_invocable<_Fn _QUALS, _Args...>::value>> \
-	void operator()(_Args&&... __args) _QUALS = delete;
-
-      _GLIBCXX_NOT_FN_CALL_OP( & )
-      _GLIBCXX_NOT_FN_CALL_OP( const & )
-      _GLIBCXX_NOT_FN_CALL_OP( && )
-      _GLIBCXX_NOT_FN_CALL_OP( const && )
-#undef _GLIBCXX_NOT_FN_CALL_OP
-
-    private:
-      _Fn _M_fn;
-    };
-
   template<typename _Tp, typename _Pred>
     struct __is_byte_like : false_type { };
 
diff --git a/libstdc++-v3/include/std/string b/libstdc++-v3/include/std/string
index fd69e9cb746..319795870a6 100644
--- a/libstdc++-v3/include/std/string
+++ b/libstdc++-v3/include/std/string
@@ -51,7 +51,7 @@
 #include <bits/stl_function.h> // For less
 #include <ext/numeric_traits.h>
 #include <bits/stl_algobase.h>
-#include <bits/refwrap.h>
+#include <bits/move.h>
 #include <bits/range_access.h>
 #include <bits/basic_string.h>
 #include <bits/basic_string.tcc>
@@ -99,11 +99,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     inline typename basic_string<_CharT, _Traits, _Alloc>::size_type
     erase_if(basic_string<_CharT, _Traits, _Alloc>& __cont, _Predicate __pred)
     {
-      using namespace __gnu_cxx;
       const auto __osz = __cont.size();
       const auto __end = __cont.end();
       auto __removed = std::__remove_if(__cont.begin(), __end,
-					__ops::__pred_iter(std::ref(__pred)));
+					std::move(__pred));
       __cont.erase(__removed, __end);
       return __osz - __cont.size();
     }
@@ -118,7 +117,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       const auto __osz = __cont.size();
       const auto __end = __cont.end();
       auto __removed = std::__remove_if(__cont.begin(), __end,
-					__ops::__iter_equals_val(__value));
+					__ops::__equal_val(__value));
       __cont.erase(__removed, __end);
       return __osz - __cont.size();
     }
diff --git a/libstdc++-v3/include/std/vector b/libstdc++-v3/include/std/vector
index 705bcdc9c08..56e0d207139 100644
--- a/libstdc++-v3/include/std/vector
+++ b/libstdc++-v3/include/std/vector
@@ -67,7 +67,7 @@
 #include <bits/stl_uninitialized.h>
 #include <bits/stl_vector.h>
 #include <bits/stl_bvector.h>
-#include <bits/refwrap.h>
+#include <bits/move.h>
 #include <bits/range_access.h>
 
 #ifndef _GLIBCXX_EXPORT_TEMPLATE
@@ -116,12 +116,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     inline typename vector<_Tp, _Alloc>::size_type
     erase_if(vector<_Tp, _Alloc>& __cont, _Predicate __pred)
     {
-      using namespace __gnu_cxx;
       _GLIBCXX_STD_C::vector<_Tp, _Alloc>& __ucont = __cont;
       const auto __osz = __cont.size();
       const auto __end = __ucont.end();
       auto __removed = std::__remove_if(__ucont.begin(), __end,
-					__ops::__pred_iter(std::ref(__pred)));
+					std::move(__pred));
       if (__removed != __end)
 	{
 	  __cont.erase(__niter_wrap(__cont.begin(), __removed),
@@ -143,7 +142,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       const auto __osz = __cont.size();
       const auto __end = __ucont.end();
       auto __removed = std::__remove_if(__ucont.begin(), __end,
-					__ops::__iter_equals_val(__value));
+					__ops::__equal_val(__value));
       if (__removed != __end)
 	{
 	  __cont.erase(__niter_wrap(__cont.begin(), __removed),
diff --git a/libstdc++-v3/src/c++17/memory_resource.cc b/libstdc++-v3/src/c++17/memory_resource.cc
index f9958c690f8..86bae3e3d7c 100644
--- a/libstdc++-v3/src/c++17/memory_resource.cc
+++ b/libstdc++-v3/src/c++17/memory_resource.cc
@@ -26,6 +26,7 @@
 #include <algorithm>			// lower_bound, rotate
 #include <atomic>
 #include <bit>				// has_single_bit, bit_ceil, bit_width
+#include <functional>			// less_equal
 #include <new>
 #include <bits/move.h>			// std::__exchange
 #if ATOMIC_POINTER_LOCK_FREE != 2
diff --git a/libstdc++-v3/testsuite/25_algorithms/inplace_merge/1.cc b/libstdc++-v3/testsuite/25_algorithms/inplace_merge/1.cc
index c9f1839f731..81270f05cef 100644
--- a/libstdc++-v3/testsuite/25_algorithms/inplace_merge/1.cc
+++ b/libstdc++-v3/testsuite/25_algorithms/inplace_merge/1.cc
@@ -21,6 +21,7 @@
 // { dg-require-effective-target hosted }
 
 #include <algorithm>
+#include <vector>
 #include <testsuite_hooks.h>
 #include <testsuite_iterators.h>
 #include <testsuite_new_operators.h>
@@ -119,6 +120,17 @@ test4()
     }
 }
 
+bool bs[] = { false, false, true, false, true, true };
+std::vector<bool> v(6);
+
+void
+test5()
+{
+  v.assign(bs, bs + 6);
+  inplace_merge(v.begin(), v.begin() + 3, v.end());
+  VERIFY( !v[0] && !v[1] && !v[2] && v[3] && v[4] && v[5] );
+}
+
 int 
 main()
 {
@@ -129,14 +141,17 @@ main()
   __gnu_test::set_new_limit(sizeof(S) * 4);
   test3();
   test4();
+  test5();
 
   __gnu_test::set_new_limit(sizeof(S));
   test3();
   test4();
+  test5();
 
   __gnu_test::set_new_limit(0);
   test3();
   test4();
+  test5();
 
   return 0;
 }


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