Update clang, llvm, lld, lldb, compiler-rt and libc++ to 4.0.0 release:

MFC r309142 (by emaste):

Add WITH_LLD_AS_LD build knob

If set it installs LLD as /usr/bin/ld.  LLD (as of version 3.9) is not
capable of linking the world and kernel, but can self-host and link many
substantial applications. GNU ld continues to be used for the world and
kernel build, regardless of how this knob is set.

It is on by default for arm64, and off for all other CPU architectures.

Sponsored by:	The FreeBSD Foundation

MFC r310840:

Reapply 310775, now it also builds correctly if lldb is disabled:

Move llvm-objdump from CLANG_EXTRAS to installed by default

We currently install three tools from binutils 2.17.50: as, ld, and
objdump. Work is underway to migrate to a permissively-licensed
tool-chain, with one goal being the retirement of binutils 2.17.50.

LLVM's llvm-objdump is intended to be compatible with GNU objdump
although it is currently missing some options and may have formatting
differences. Enable it by default for testing and further investigation.
It may later be changed to install as /usr/bin/objdump, it becomes a
fully viable replacement.

Reviewed by:	emaste
Differential Revision:	https://reviews.freebsd.org/D8879

MFC r312855 (by emaste):

Rename LLD_AS_LD to LLD_IS_LD, for consistency with CLANG_IS_CC

Reported by:	Dan McGregor <dan.mcgregor usask.ca>

MFC r313559 | glebius | 2017-02-10 18:34:48 +0100 (Fri, 10 Feb 2017) | 5 lines

Don't check struct rtentry on FreeBSD, it is an internal kernel structure.
On other systems it may be API structure for SIOCADDRT/SIOCDELRT.

Reviewed by:	emaste, dim

MFC r314152 (by jkim):

Remove an assembler flag, which is redundant since r309124.  The upstream
took care of it by introducing a macro NO_EXEC_STACK_DIRECTIVE.

http://llvm.org/viewvc/llvm-project?rev=273500&view=rev

Reviewed by:	dim

MFC r314564:

Upgrade our copies of clang, llvm, lld, lldb, compiler-rt and libc++ to
4.0.0 (branches/release_40 296509).  The release will follow soon.

Please note that from 3.5.0 onwards, clang, llvm and lldb require C++11
support to build; see UPDATING for more information.

Also note that as of 4.0.0, lld should be able to link the base system
on amd64 and aarch64.  See the WITH_LLD_IS_LLD setting in src.conf(5).
Though please be aware that this is work in progress.

Release notes for llvm, clang and lld will be available here:
<http://releases.llvm.org/4.0.0/docs/ReleaseNotes.html>
<http://releases.llvm.org/4.0.0/tools/clang/docs/ReleaseNotes.html>
<http://releases.llvm.org/4.0.0/tools/lld/docs/ReleaseNotes.html>

Thanks to Ed Maste, Jan Beich, Antoine Brodin and Eric Fiselier for
their help.

Relnotes:	yes
Exp-run:	antoine
PR:		215969, 216008

MFC r314708:

For now, revert r287232 from upstream llvm trunk (by Daniil Fukalov):

  [SCEV] limit recursion depth of CompareSCEVComplexity

  Summary:
  CompareSCEVComplexity goes too deep (50+ on a quite a big unrolled
  loop) and runs almost infinite time.

  Added cache of "equal" SCEV pairs to earlier cutoff of further
  estimation. Recursion depth limit was also introduced as a parameter.

  Reviewers: sanjoy

  Subscribers: mzolotukhin, tstellarAMD, llvm-commits

  Differential Revision: https://reviews.llvm.org/D26389

This commit is the cause of excessive compile times on skein_block.c
(and possibly other files) during kernel builds on amd64.

We never saw the problematic behavior described in this upstream commit,
so for now it is better to revert it.  An upstream bug has been filed
here: https://bugs.llvm.org/show_bug.cgi?id=32142

Reported by:	mjg

MFC r314795:

Reapply r287232 from upstream llvm trunk (by Daniil Fukalov):

  [SCEV] limit recursion depth of CompareSCEVComplexity

  Summary:
  CompareSCEVComplexity goes too deep (50+ on a quite a big unrolled
  loop) and runs almost infinite time.

  Added cache of "equal" SCEV pairs to earlier cutoff of further
  estimation. Recursion depth limit was also introduced as a parameter.

  Reviewers: sanjoy

  Subscribers: mzolotukhin, tstellarAMD, llvm-commits

  Differential Revision: https://reviews.llvm.org/D26389

Pull in r296992 from upstream llvm trunk (by Sanjoy Das):

  [SCEV] Decrease the recursion threshold for CompareValueComplexity

  Fixes PR32142.

  r287232 accidentally increased the recursion threshold for
  CompareValueComplexity from 2 to 32.  This change reverses that
  change by introducing a separate flag for CompareValueComplexity's
  threshold.

The latter revision fixes the excessive compile times for skein_block.c.

MFC r314907 | mmel | 2017-03-08 12:40:27 +0100 (Wed, 08 Mar 2017) | 7 lines

Unbreak ARMv6 world.

The new compiler_rt library imported with clang 4.0.0 have several fatal
issues (non-functional __udivsi3 for example) with ARM specific instrict
functions. As temporary workaround, until upstream solve these problems,
disable all thumb[1][2] related feature.

MFC r315016:

Update clang, llvm, lld, lldb, compiler-rt and libc++ to 4.0.0 release.
We were already very close to the last release candidate, so this is a
pretty minor update.

Relnotes:	yes

MFC r316005:

Revert r314907, and pull in r298713 from upstream compiler-rt trunk (by
Weiming Zhao):

  builtins: Select correct code fragments when compiling for Thumb1/Thum2/ARM ISA.

  Summary:
  Value of __ARM_ARCH_ISA_THUMB isn't based on the actual compilation
  mode (-mthumb, -marm), it reflect's capability of given CPU.

  Due to this:
   - use  __tbumb__ and __thumb2__ insteand of __ARM_ARCH_ISA_THUMB
   - use '.thumb' directive consistently  in all affected files
   - decorate all thumb functions using
     DEFINE_COMPILERRT_THUMB_FUNCTION()

  ---------
  Note: This patch doesn't fix broken Thumb1 variant of __udivsi3 !

  Reviewers: weimingz, rengolin, compnerd

  Subscribers: aemerson, dim

  Differential Revision: https://reviews.llvm.org/D30938

Discussed with:	mmel

1 files changed, 280 insertions, 233 deletions

diff --git a/contrib/libc++/include/iterator b/contrib/libc++/include/iterator
index 0caabbb..b8f6570 100644
--- a/contrib/libc++/include/iterator
+++ b/contrib/libc++/include/iterator
@@ -89,57 +89,60 @@ public:
     typedef typename iterator_traits<Iterator>::reference       reference;
     typedef typename iterator_traits<Iterator>::pointer         pointer;
 
-    reverse_iterator();
-    explicit reverse_iterator(Iterator x);
-    template <class U> reverse_iterator(const reverse_iterator<U>& u);
-    Iterator base() const;
-    reference operator*() const;
-    pointer   operator->() const;
-    reverse_iterator& operator++();
-    reverse_iterator  operator++(int);
-    reverse_iterator& operator--();
-    reverse_iterator  operator--(int);
-    reverse_iterator  operator+ (difference_type n) const;
-    reverse_iterator& operator+=(difference_type n);
-    reverse_iterator  operator- (difference_type n) const;
-    reverse_iterator& operator-=(difference_type n);
-    reference         operator[](difference_type n) const;
+    constexpr reverse_iterator();
+    constexpr explicit reverse_iterator(Iterator x);
+    template <class U> constexpr reverse_iterator(const reverse_iterator<U>& u);
+    template <class U> constexpr reverse_iterator& operator=(const reverse_iterator<U>& u);
+    constexpr Iterator base() const;
+    constexpr reference operator*() const;
+    constexpr pointer   operator->() const;
+    constexpr reverse_iterator& operator++();
+    constexpr reverse_iterator  operator++(int);
+    constexpr reverse_iterator& operator--();
+    constexpr reverse_iterator  operator--(int);
+    constexpr reverse_iterator  operator+ (difference_type n) const;
+    constexpr reverse_iterator& operator+=(difference_type n);
+    constexpr reverse_iterator  operator- (difference_type n) const;
+    constexpr reverse_iterator& operator-=(difference_type n);
+    constexpr reference         operator[](difference_type n) const;
 };
 
 template <class Iterator1, class Iterator2>
-bool
+constexpr bool                          // constexpr in C++17
 operator==(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
 
 template <class Iterator1, class Iterator2>
-bool
+constexpr bool                          // constexpr in C++17
 operator<(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
 
 template <class Iterator1, class Iterator2>
-bool
+constexpr bool                          // constexpr in C++17
 operator!=(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
 
 template <class Iterator1, class Iterator2>
-bool
+constexpr bool                          // constexpr in C++17
 operator>(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
 
 template <class Iterator1, class Iterator2>
-bool
+constexpr bool                          // constexpr in C++17
 operator>=(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
 
 template <class Iterator1, class Iterator2>
-bool
+constexpr bool                          // constexpr in C++17
 operator<=(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y);
 
 template <class Iterator1, class Iterator2>
-auto
+constexpr auto
 operator-(const reverse_iterator<Iterator1>& x, const reverse_iterator<Iterator2>& y)
--> decltype(__y.base() - __x.base());
+-> decltype(__y.base() - __x.base());   // constexpr in C++17
 
 template <class Iterator>
-reverse_iterator<Iterator>
-operator+(typename reverse_iterator<Iterator>::difference_type n, const reverse_iterator<Iterator>& x);
+constexpr reverse_iterator<Iterator>
+operator+(typename reverse_iterator<Iterator>::difference_type n, 
+          const reverse_iterator<Iterator>& x);   // constexpr in C++17
 
-template <class Iterator> reverse_iterator<Iterator> make_reverse_iterator(Iterator i); // C++14
+template <class Iterator>
+constexpr reverse_iterator<Iterator> make_reverse_iterator(Iterator i); // C++14, constexpr in C++17
 
 template <class Container>
 class back_insert_iterator
@@ -216,61 +219,64 @@ public:
     typedef typename iterator_traits<Iterator>::iterator_category iterator_category;
     typedef value_type&&                                          reference;
  
-    move_iterator();
-    explicit move_iterator(Iterator i);
-    template <class U> move_iterator(const move_iterator<U>& u);
-    template <class U> move_iterator& operator=(const move_iterator<U>& u);
-    iterator_type base() const;
-    reference operator*() const;
-    pointer operator->() const;
-    move_iterator& operator++();
-    move_iterator operator++(int);
-    move_iterator& operator--();
-    move_iterator operator--(int);
-    move_iterator operator+(difference_type n) const; 
-    move_iterator& operator+=(difference_type n); 
-    move_iterator operator-(difference_type n) const; 
-    move_iterator& operator-=(difference_type n); 
-    unspecified operator[](difference_type n) const;
+    constexpr move_iterator();  // all the constexprs are in C++17
+    constexpr explicit move_iterator(Iterator i);
+    template <class U>
+      constexpr move_iterator(const move_iterator<U>& u);
+    template <class U>
+      constexpr move_iterator& operator=(const move_iterator<U>& u);
+    constexpr iterator_type base() const;
+    constexpr reference operator*() const;
+    constexpr pointer operator->() const;
+    constexpr move_iterator& operator++();
+    constexpr move_iterator operator++(int);
+    constexpr move_iterator& operator--();
+    constexpr move_iterator operator--(int);
+    constexpr move_iterator operator+(difference_type n) const; 
+    constexpr move_iterator& operator+=(difference_type n); 
+    constexpr move_iterator operator-(difference_type n) const; 
+    constexpr move_iterator& operator-=(difference_type n); 
+    constexpr unspecified operator[](difference_type n) const;
 private:
     Iterator current; // exposition only
 };
 
 template <class Iterator1, class Iterator2>
-bool
+constexpr bool   // constexpr in C++17
 operator==(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
 
 template <class Iterator1, class Iterator2>
-bool
+constexpr bool   // constexpr in C++17
 operator!=(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
 
 template <class Iterator1, class Iterator2>
-bool
+constexpr bool   // constexpr in C++17
 operator<(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
 
 template <class Iterator1, class Iterator2>
-bool
+constexpr bool   // constexpr in C++17
 operator<=(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
 
 template <class Iterator1, class Iterator2>
-bool
+constexpr bool   // constexpr in C++17
 operator>(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
 
 template <class Iterator1, class Iterator2>
-bool
+constexpr bool   // constexpr in C++17
 operator>=(const move_iterator<Iterator1>& x, const move_iterator<Iterator2>& y);
 
 template <class Iterator1, class Iterator2>
-auto
+constexpr auto   // constexpr in C++17
 operator-(const move_iterator<Iterator1>& x,
           const move_iterator<Iterator2>& y) -> decltype(x.base() - y.base());
 
 template <class Iterator>
-move_iterator<Iterator> operator+(typename move_iterator<Iterator>::difference_type n, 
-                                     const move_iterator<Iterator>& x);
+constexpr move_iterator<Iterator> operator+(   // constexpr in C++17
+            typename move_iterator<Iterator>::difference_type n, 
+            const move_iterator<Iterator>& x);
 
-template <class Iterator>
-move_iterator<Iterator> make_move_iterator(const Iterator& i);
+template <class Iterator>   // constexpr in C++17
+constexpr  move_iterator<Iterator> make_move_iterator(const Iterator& i);
 
 
 template <class T, class charT = char, class traits = char_traits<charT>, class Distance = ptrdiff_t>
@@ -372,25 +378,25 @@ public:
     bool failed() const noexcept;
 };
 
-template <class C> auto begin(C& c) -> decltype(c.begin());
-template <class C> auto begin(const C& c) -> decltype(c.begin());
-template <class C> auto end(C& c) -> decltype(c.end());
-template <class C> auto end(const C& c) -> decltype(c.end());
-template <class T, size_t N> T* begin(T (&array)[N]);
-template <class T, size_t N> T* end(T (&array)[N]);
-
-template <class C> auto cbegin(const C& c) -> decltype(std::begin(c));        // C++14
-template <class C> auto cend(const C& c) -> decltype(std::end(c));            // C++14
-template <class C> auto rbegin(C& c) -> decltype(c.rbegin());                 // C++14
-template <class C> auto rbegin(const C& c) -> decltype(c.rbegin());           // C++14
-template <class C> auto rend(C& c) -> decltype(c.rend());                     // C++14
-template <class C> auto rend(const C& c) -> decltype(c.rend());               // C++14
-template <class E> reverse_iterator<const E*> rbegin(initializer_list<E> il); // C++14
-template <class E> reverse_iterator<const E*> rend(initializer_list<E> il);   // C++14
-template <class T, size_t N> reverse_iterator<T*> rbegin(T (&array)[N]);      // C++14
-template <class T, size_t N> reverse_iterator<T*> rend(T (&array)[N]);        // C++14
-template <class C> auto crbegin(const C& c) -> decltype(std::rbegin(c));      // C++14
-template <class C> auto crend(const C& c) -> decltype(std::rend(c));          // C++14
+template <class C> constexpr auto begin(C& c) -> decltype(c.begin());
+template <class C> constexpr auto begin(const C& c) -> decltype(c.begin());
+template <class C> constexpr auto end(C& c) -> decltype(c.end());
+template <class C> constexpr auto end(const C& c) -> decltype(c.end());
+template <class T, size_t N> constexpr T* begin(T (&array)[N]);
+template <class T, size_t N> constexpr T* end(T (&array)[N]);
+
+template <class C> auto constexpr cbegin(const C& c) -> decltype(std::begin(c));        // C++14
+template <class C> auto constexpr cend(const C& c) -> decltype(std::end(c));            // C++14
+template <class C> auto constexpr rbegin(C& c) -> decltype(c.rbegin());                 // C++14
+template <class C> auto constexpr rbegin(const C& c) -> decltype(c.rbegin());           // C++14
+template <class C> auto constexpr rend(C& c) -> decltype(c.rend());                     // C++14
+template <class C> constexpr auto rend(const C& c) -> decltype(c.rend());               // C++14
+template <class E> reverse_iterator<const E*> constexpr rbegin(initializer_list<E> il); // C++14
+template <class E> reverse_iterator<const E*> constexpr rend(initializer_list<E> il);   // C++14
+template <class T, size_t N> reverse_iterator<T*> constexpr rbegin(T (&array)[N]);      // C++14
+template <class T, size_t N> reverse_iterator<T*> constexpr rend(T (&array)[N]);        // C++14
+template <class C> constexpr auto crbegin(const C& c) -> decltype(std::rbegin(c));      // C++14
+template <class C> constexpr auto crend(const C& c) -> decltype(std::rend(c));          // C++14
 
 // 24.8, container access:
 template <class C> constexpr auto size(const C& c) -> decltype(c.size());         // C++17
@@ -425,11 +431,11 @@ template <class E> constexpr const E* data(initializer_list<E> il) noexcept;
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-struct _LIBCPP_TYPE_VIS_ONLY input_iterator_tag {};
-struct _LIBCPP_TYPE_VIS_ONLY output_iterator_tag {};
-struct _LIBCPP_TYPE_VIS_ONLY forward_iterator_tag       : public input_iterator_tag {};
-struct _LIBCPP_TYPE_VIS_ONLY bidirectional_iterator_tag : public forward_iterator_tag {};
-struct _LIBCPP_TYPE_VIS_ONLY random_access_iterator_tag : public bidirectional_iterator_tag {};
+struct _LIBCPP_TEMPLATE_VIS input_iterator_tag {};
+struct _LIBCPP_TEMPLATE_VIS output_iterator_tag {};
+struct _LIBCPP_TEMPLATE_VIS forward_iterator_tag       : public input_iterator_tag {};
+struct _LIBCPP_TEMPLATE_VIS bidirectional_iterator_tag : public forward_iterator_tag {};
+struct _LIBCPP_TEMPLATE_VIS random_access_iterator_tag : public bidirectional_iterator_tag {};
 
 template <class _Tp>
 struct __has_iterator_category
@@ -472,11 +478,11 @@ struct __iterator_traits<_Iter, true>
 //    the client expects instead of failing at compile time.
 
 template <class _Iter>
-struct _LIBCPP_TYPE_VIS_ONLY iterator_traits
+struct _LIBCPP_TEMPLATE_VIS iterator_traits
     : __iterator_traits<_Iter, __has_iterator_category<_Iter>::value> {};
 
 template<class _Tp>
-struct _LIBCPP_TYPE_VIS_ONLY iterator_traits<_Tp*>
+struct _LIBCPP_TEMPLATE_VIS iterator_traits<_Tp*>
 {
     typedef ptrdiff_t difference_type;
     typedef typename remove_const<_Tp>::type value_type;
@@ -508,12 +514,12 @@ struct __is_random_access_iterator : public __has_iterator_category_convertible_
 template <class _Tp>
 struct __is_exactly_input_iterator
     : public integral_constant<bool, 
-    	 __has_iterator_category_convertible_to<_Tp, input_iterator_tag>::value && 
-    	!__has_iterator_category_convertible_to<_Tp, forward_iterator_tag>::value> {};
+         __has_iterator_category_convertible_to<_Tp, input_iterator_tag>::value && 
+        !__has_iterator_category_convertible_to<_Tp, forward_iterator_tag>::value> {};
 
 template<class _Category, class _Tp, class _Distance = ptrdiff_t,
          class _Pointer = _Tp*, class _Reference = _Tp&>
-struct _LIBCPP_TYPE_VIS_ONLY iterator
+struct _LIBCPP_TEMPLATE_VIS iterator
 {
     typedef _Tp        value_type;
     typedef _Distance  difference_type;
@@ -610,7 +616,7 @@ prev(_BidiretionalIter __x,
 }
 
 template <class _Iter>
-class _LIBCPP_TYPE_VIS_ONLY reverse_iterator
+class _LIBCPP_TEMPLATE_VIS reverse_iterator
     : public iterator<typename iterator_traits<_Iter>::iterator_category,
                       typename iterator_traits<_Iter>::value_type,
                       typename iterator_traits<_Iter>::difference_type,
@@ -618,7 +624,7 @@ class _LIBCPP_TYPE_VIS_ONLY reverse_iterator
                       typename iterator_traits<_Iter>::reference>
 {
 private:
-    mutable _Iter __t;  // no longer used as of LWG #2360, not removed due to ABI break
+    /*mutable*/ _Iter __t;  // no longer used as of LWG #2360, not removed due to ABI break
 protected:
     _Iter current;
 public:
@@ -627,33 +633,45 @@ public:
     typedef typename iterator_traits<_Iter>::reference       reference;
     typedef typename iterator_traits<_Iter>::pointer         pointer;
 
-    _LIBCPP_INLINE_VISIBILITY reverse_iterator() : current() {}
-    _LIBCPP_INLINE_VISIBILITY explicit reverse_iterator(_Iter __x) : __t(__x), current(__x) {}
-    template <class _Up> _LIBCPP_INLINE_VISIBILITY reverse_iterator(const reverse_iterator<_Up>& __u)
-        : __t(__u.base()), current(__u.base()) {}
-    _LIBCPP_INLINE_VISIBILITY _Iter base() const {return current;}
-    _LIBCPP_INLINE_VISIBILITY reference operator*() const {_Iter __tmp = current; return *--__tmp;}
-    _LIBCPP_INLINE_VISIBILITY pointer  operator->() const {return _VSTD::addressof(operator*());}
-    _LIBCPP_INLINE_VISIBILITY reverse_iterator& operator++() {--current; return *this;}
-    _LIBCPP_INLINE_VISIBILITY reverse_iterator  operator++(int)
-        {reverse_iterator __tmp(*this); --current; return __tmp;}
-    _LIBCPP_INLINE_VISIBILITY reverse_iterator& operator--() {++current; return *this;}
-    _LIBCPP_INLINE_VISIBILITY reverse_iterator  operator--(int)
-        {reverse_iterator __tmp(*this); ++current; return __tmp;}
-    _LIBCPP_INLINE_VISIBILITY reverse_iterator  operator+ (difference_type __n) const
-        {return reverse_iterator(current - __n);}
-    _LIBCPP_INLINE_VISIBILITY reverse_iterator& operator+=(difference_type __n)
-        {current -= __n; return *this;}
-    _LIBCPP_INLINE_VISIBILITY reverse_iterator  operator- (difference_type __n) const
-        {return reverse_iterator(current + __n);}
-    _LIBCPP_INLINE_VISIBILITY reverse_iterator& operator-=(difference_type __n)
-        {current += __n; return *this;}
-    _LIBCPP_INLINE_VISIBILITY reference         operator[](difference_type __n) const
-        {return *(*this + __n);}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    reverse_iterator() : __t(), current() {}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    explicit reverse_iterator(_Iter __x) : __t(__x), current(__x) {}
+    template <class _Up>
+        _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+        reverse_iterator(const reverse_iterator<_Up>& __u) : __t(__u.base()), current(__u.base()) {}
+    template <class _Up>
+        _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+        reverse_iterator& operator=(const reverse_iterator<_Up>& __u)
+            { __t = current = __u.base(); return *this; }
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    _Iter base() const {return current;}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    reference operator*() const {_Iter __tmp = current; return *--__tmp;}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    pointer  operator->() const {return _VSTD::addressof(operator*());}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    reverse_iterator& operator++() {--current; return *this;}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    reverse_iterator  operator++(int) {reverse_iterator __tmp(*this); --current; return __tmp;}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    reverse_iterator& operator--() {++current; return *this;}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    reverse_iterator  operator--(int) {reverse_iterator __tmp(*this); ++current; return __tmp;}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    reverse_iterator  operator+ (difference_type __n) const {return reverse_iterator(current - __n);}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    reverse_iterator& operator+=(difference_type __n) {current -= __n; return *this;}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    reverse_iterator  operator- (difference_type __n) const {return reverse_iterator(current + __n);}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    reverse_iterator& operator-=(difference_type __n) {current += __n; return *this;}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    reference         operator[](difference_type __n) const {return *(*this + __n);}
 };
 
 template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 bool
 operator==(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
 {
@@ -661,7 +679,7 @@ operator==(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>&
 }
 
 template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 bool
 operator<(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
 {
@@ -669,7 +687,7 @@ operator<(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& _
 }
 
 template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 bool
 operator!=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
 {
@@ -677,7 +695,7 @@ operator!=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>&
 }
 
 template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 bool
 operator>(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
 {
@@ -685,7 +703,7 @@ operator>(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& _
 }
 
 template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 bool
 operator>=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
 {
@@ -693,7 +711,7 @@ operator>=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>&
 }
 
 template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 bool
 operator<=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
 {
@@ -702,7 +720,7 @@ operator<=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>&
 
 #ifndef _LIBCPP_CXX03_LANG
 template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 auto
 operator-(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
 -> decltype(__y.base() - __x.base())
@@ -720,7 +738,7 @@ operator-(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& _
 #endif
 
 template <class _Iter>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 reverse_iterator<_Iter>
 operator+(typename reverse_iterator<_Iter>::difference_type __n, const reverse_iterator<_Iter>& __x)
 {
@@ -729,7 +747,7 @@ operator+(typename reverse_iterator<_Iter>::difference_type __n, const reverse_i
 
 #if _LIBCPP_STD_VER > 11
 template <class _Iter>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 reverse_iterator<_Iter> make_reverse_iterator(_Iter __i)
 {
     return reverse_iterator<_Iter>(__i);
@@ -737,7 +755,7 @@ reverse_iterator<_Iter> make_reverse_iterator(_Iter __i)
 #endif
 
 template <class _Container>
-class _LIBCPP_TYPE_VIS_ONLY back_insert_iterator
+class _LIBCPP_TEMPLATE_VIS back_insert_iterator
     : public iterator<output_iterator_tag,
                       void,
                       void,
@@ -770,7 +788,7 @@ back_inserter(_Container& __x)
 }
 
 template <class _Container>
-class _LIBCPP_TYPE_VIS_ONLY front_insert_iterator
+class _LIBCPP_TEMPLATE_VIS front_insert_iterator
     : public iterator<output_iterator_tag,
                       void,
                       void,
@@ -803,7 +821,7 @@ front_inserter(_Container& __x)
 }
 
 template <class _Container>
-class _LIBCPP_TYPE_VIS_ONLY insert_iterator
+class _LIBCPP_TEMPLATE_VIS insert_iterator
     : public iterator<output_iterator_tag,
                       void,
                       void,
@@ -839,7 +857,7 @@ inserter(_Container& __x, typename _Container::iterator __i)
 
 template <class _Tp, class _CharT = char,
           class _Traits = char_traits<_CharT>, class _Distance = ptrdiff_t>
-class _LIBCPP_TYPE_VIS_ONLY istream_iterator
+class _LIBCPP_TEMPLATE_VIS istream_iterator
     : public iterator<input_iterator_tag, _Tp, _Distance, const _Tp*, const _Tp&>
 {
 public:
@@ -878,7 +896,7 @@ public:
 };
 
 template <class _Tp, class _CharT = char, class _Traits = char_traits<_CharT> >
-class _LIBCPP_TYPE_VIS_ONLY ostream_iterator
+class _LIBCPP_TEMPLATE_VIS ostream_iterator
     : public iterator<output_iterator_tag, void, void, void, void>
 {
 public:
@@ -889,9 +907,9 @@ private:
     ostream_type* __out_stream_;
     const char_type* __delim_;
 public:
-    _LIBCPP_INLINE_VISIBILITY ostream_iterator(ostream_type& __s)
+    _LIBCPP_INLINE_VISIBILITY ostream_iterator(ostream_type& __s) _NOEXCEPT
         : __out_stream_(_VSTD::addressof(__s)), __delim_(0) {}
-    _LIBCPP_INLINE_VISIBILITY ostream_iterator(ostream_type& __s, const _CharT* __delimiter)
+    _LIBCPP_INLINE_VISIBILITY ostream_iterator(ostream_type& __s, const _CharT* __delimiter) _NOEXCEPT
         : __out_stream_(_VSTD::addressof(__s)), __delim_(__delimiter) {}
     _LIBCPP_INLINE_VISIBILITY ostream_iterator& operator=(const _Tp& __value_)
         {
@@ -907,7 +925,7 @@ public:
 };
 
 template<class _CharT, class _Traits>
-class _LIBCPP_TYPE_VIS_ONLY istreambuf_iterator
+class _LIBCPP_TEMPLATE_VIS istreambuf_iterator
     : public iterator<input_iterator_tag, _CharT,
                       typename _Traits::off_type, _CharT*,
                       _CharT>
@@ -978,7 +996,7 @@ bool operator!=(const istreambuf_iterator<_CharT,_Traits>& __a,
                 {return !__a.equal(__b);}
 
 template <class _CharT, class _Traits>
-class _LIBCPP_TYPE_VIS_ONLY ostreambuf_iterator
+class _LIBCPP_TEMPLATE_VIS ostreambuf_iterator
     : public iterator<output_iterator_tag, void, void, void, void>
 {
 public:
@@ -1019,7 +1037,7 @@ public:
 };
 
 template <class _Iter>
-class _LIBCPP_TYPE_VIS_ONLY move_iterator
+class _LIBCPP_TEMPLATE_VIS move_iterator
 {
 private:
     _Iter __i;
@@ -1040,37 +1058,40 @@ public:
     typedef typename iterator_traits<iterator_type>::reference reference;
 #endif
 
-    _LIBCPP_INLINE_VISIBILITY move_iterator() : __i() {}
-    _LIBCPP_INLINE_VISIBILITY explicit move_iterator(_Iter __x) : __i(__x) {}
-    template <class _Up> _LIBCPP_INLINE_VISIBILITY move_iterator(const move_iterator<_Up>& __u)
-        : __i(__u.base()) {}
-    _LIBCPP_INLINE_VISIBILITY _Iter base() const {return __i;}
-    _LIBCPP_INLINE_VISIBILITY reference operator*() const {
-      return static_cast<reference>(*__i);
-    }
-    _LIBCPP_INLINE_VISIBILITY pointer  operator->() const { return __i;}
-    _LIBCPP_INLINE_VISIBILITY move_iterator& operator++() {++__i; return *this;}
-    _LIBCPP_INLINE_VISIBILITY move_iterator  operator++(int)
-        {move_iterator __tmp(*this); ++__i; return __tmp;}
-    _LIBCPP_INLINE_VISIBILITY move_iterator& operator--() {--__i; return *this;}
-    _LIBCPP_INLINE_VISIBILITY move_iterator  operator--(int)
-        {move_iterator __tmp(*this); --__i; return __tmp;}
-    _LIBCPP_INLINE_VISIBILITY move_iterator  operator+ (difference_type __n) const
-        {return move_iterator(__i + __n);}
-    _LIBCPP_INLINE_VISIBILITY move_iterator& operator+=(difference_type __n)
-        {__i += __n; return *this;}
-    _LIBCPP_INLINE_VISIBILITY move_iterator  operator- (difference_type __n) const
-        {return move_iterator(__i - __n);}
-    _LIBCPP_INLINE_VISIBILITY move_iterator& operator-=(difference_type __n)
-        {__i -= __n; return *this;}
-    _LIBCPP_INLINE_VISIBILITY reference         operator[](difference_type __n) const
-    {
-      return static_cast<reference>(__i[__n]);
-    }
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    move_iterator() : __i() {}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    explicit move_iterator(_Iter __x) : __i(__x) {}
+    template <class _Up>
+      _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+      move_iterator(const move_iterator<_Up>& __u) : __i(__u.base()) {}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 _Iter base() const {return __i;}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 
+    reference operator*() const { return static_cast<reference>(*__i); }
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    pointer  operator->() const { return __i;}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    move_iterator& operator++() {++__i; return *this;}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    move_iterator  operator++(int) {move_iterator __tmp(*this); ++__i; return __tmp;}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    move_iterator& operator--() {--__i; return *this;}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    move_iterator  operator--(int) {move_iterator __tmp(*this); --__i; return __tmp;}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    move_iterator  operator+ (difference_type __n) const {return move_iterator(__i + __n);}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    move_iterator& operator+=(difference_type __n) {__i += __n; return *this;}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    move_iterator  operator- (difference_type __n) const {return move_iterator(__i - __n);}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    move_iterator& operator-=(difference_type __n) {__i -= __n; return *this;}
+    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+    reference operator[](difference_type __n) const { return static_cast<reference>(__i[__n]); }
 };
 
 template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 bool
 operator==(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
 {
@@ -1078,7 +1099,7 @@ operator==(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
 }
 
 template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 bool
 operator<(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
 {
@@ -1086,7 +1107,7 @@ operator<(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
 }
 
 template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 bool
 operator!=(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
 {
@@ -1094,7 +1115,7 @@ operator!=(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
 }
 
 template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 bool
 operator>(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
 {
@@ -1102,7 +1123,7 @@ operator>(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
 }
 
 template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 bool
 operator>=(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
 {
@@ -1110,7 +1131,7 @@ operator>=(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
 }
 
 template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 bool
 operator<=(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
 {
@@ -1119,7 +1140,7 @@ operator<=(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
 
 #ifndef _LIBCPP_CXX03_LANG
 template <class _Iter1, class _Iter2>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 auto
 operator-(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
 -> decltype(__x.base() - __y.base())
@@ -1137,7 +1158,7 @@ operator-(const move_iterator<_Iter1>& __x, const move_iterator<_Iter2>& __y)
 #endif
 
 template <class _Iter>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 move_iterator<_Iter>
 operator+(typename move_iterator<_Iter>::difference_type __n, const move_iterator<_Iter>& __x)
 {
@@ -1145,7 +1166,7 @@ operator+(typename move_iterator<_Iter>::difference_type __n, const move_iterato
 }
 
 template <class _Iter>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 move_iterator<_Iter>
 make_move_iterator(_Iter __i)
 {
@@ -1159,56 +1180,58 @@ template <class _Iter> class __wrap_iter;
 template <class _Iter1, class _Iter2>
 _LIBCPP_INLINE_VISIBILITY
 bool
-operator==(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
+operator==(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT_DEBUG;
 
 template <class _Iter1, class _Iter2>
 _LIBCPP_INLINE_VISIBILITY
 bool
-operator<(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
+operator<(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT_DEBUG;
 
 template <class _Iter1, class _Iter2>
 _LIBCPP_INLINE_VISIBILITY
 bool
-operator!=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
+operator!=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT_DEBUG;
 
 template <class _Iter1, class _Iter2>
 _LIBCPP_INLINE_VISIBILITY
 bool
-operator>(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
+operator>(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT_DEBUG;
 
 template <class _Iter1, class _Iter2>
 _LIBCPP_INLINE_VISIBILITY
 bool
-operator>=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
+operator>=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT_DEBUG;
 
 template <class _Iter1, class _Iter2>
 _LIBCPP_INLINE_VISIBILITY
 bool
-operator<=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
+operator<=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT_DEBUG;
 
 #ifndef _LIBCPP_CXX03_LANG
 template <class _Iter1, class _Iter2>
 _LIBCPP_INLINE_VISIBILITY
 auto
-operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
+operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT_DEBUG
 -> decltype(__x.base() - __y.base());
 #else
 template <class _Iter1, class _Iter2>
 _LIBCPP_INLINE_VISIBILITY
 typename __wrap_iter<_Iter1>::difference_type
-operator-(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
+operator-(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT_DEBUG;
 #endif
 
 template <class _Iter>
 _LIBCPP_INLINE_VISIBILITY
 __wrap_iter<_Iter>
-operator+(typename __wrap_iter<_Iter>::difference_type, __wrap_iter<_Iter>) _NOEXCEPT;
+operator+(typename __wrap_iter<_Iter>::difference_type, __wrap_iter<_Iter>) _NOEXCEPT_DEBUG;
 
 template <class _Ip, class _Op> _Op _LIBCPP_INLINE_VISIBILITY copy(_Ip, _Ip, _Op);
 template <class _B1, class _B2> _B2 _LIBCPP_INLINE_VISIBILITY copy_backward(_B1, _B1, _B2);
 template <class _Ip, class _Op> _Op _LIBCPP_INLINE_VISIBILITY move(_Ip, _Ip, _Op);
 template <class _B1, class _B2> _B2 _LIBCPP_INLINE_VISIBILITY move_backward(_B1, _B1, _B2);
 
+#if _LIBCPP_DEBUG_LEVEL < 2
+
 template <class _Tp>
 _LIBCPP_INLINE_VISIBILITY
 typename enable_if
@@ -1218,6 +1241,19 @@ typename enable_if
 >::type
 __unwrap_iter(__wrap_iter<_Tp*>);
 
+#else
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+typename enable_if
+<
+    is_trivially_copy_assignable<_Tp>::value,
+    __wrap_iter<_Tp*>
+>::type
+__unwrap_iter(__wrap_iter<_Tp*> __i);
+
+#endif
+
 template <class _Iter>
 class __wrap_iter
 {
@@ -1231,7 +1267,7 @@ public:
 private:
     iterator_type __i;
 public:
-    _LIBCPP_INLINE_VISIBILITY __wrap_iter() _NOEXCEPT
+    _LIBCPP_INLINE_VISIBILITY __wrap_iter() _NOEXCEPT_DEBUG
 #if _LIBCPP_STD_VER > 11
                 : __i{}
 #endif
@@ -1241,7 +1277,7 @@ public:
 #endif
     }
     template <class _Up> _LIBCPP_INLINE_VISIBILITY __wrap_iter(const __wrap_iter<_Up>& __u,
-        typename enable_if<is_convertible<_Up, iterator_type>::value>::type* = 0) _NOEXCEPT
+        typename enable_if<is_convertible<_Up, iterator_type>::value>::type* = 0) _NOEXCEPT_DEBUG
         : __i(__u.base())
     {
 #if _LIBCPP_DEBUG_LEVEL >= 2
@@ -1271,7 +1307,7 @@ public:
         __get_db()->__erase_i(this);
     }
 #endif
-    _LIBCPP_INLINE_VISIBILITY reference operator*() const _NOEXCEPT
+    _LIBCPP_INLINE_VISIBILITY reference operator*() const _NOEXCEPT_DEBUG
     {
 #if _LIBCPP_DEBUG_LEVEL >= 2
         _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
@@ -1279,7 +1315,7 @@ public:
 #endif
         return *__i;
     }
-    _LIBCPP_INLINE_VISIBILITY pointer  operator->() const _NOEXCEPT
+    _LIBCPP_INLINE_VISIBILITY pointer  operator->() const _NOEXCEPT_DEBUG
     {
 #if _LIBCPP_DEBUG_LEVEL >= 2
         _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
@@ -1287,7 +1323,7 @@ public:
 #endif
         return (pointer)_VSTD::addressof(*__i);
     }
-    _LIBCPP_INLINE_VISIBILITY __wrap_iter& operator++() _NOEXCEPT
+    _LIBCPP_INLINE_VISIBILITY __wrap_iter& operator++() _NOEXCEPT_DEBUG
     {
 #if _LIBCPP_DEBUG_LEVEL >= 2
         _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
@@ -1296,9 +1332,9 @@ public:
         ++__i;
         return *this;
     }
-    _LIBCPP_INLINE_VISIBILITY __wrap_iter  operator++(int) _NOEXCEPT
+    _LIBCPP_INLINE_VISIBILITY __wrap_iter  operator++(int) _NOEXCEPT_DEBUG
         {__wrap_iter __tmp(*this); ++(*this); return __tmp;}
-    _LIBCPP_INLINE_VISIBILITY __wrap_iter& operator--() _NOEXCEPT
+    _LIBCPP_INLINE_VISIBILITY __wrap_iter& operator--() _NOEXCEPT_DEBUG
     {
 #if _LIBCPP_DEBUG_LEVEL >= 2
         _LIBCPP_ASSERT(__get_const_db()->__decrementable(this),
@@ -1307,11 +1343,11 @@ public:
         --__i;
         return *this;
     }
-    _LIBCPP_INLINE_VISIBILITY __wrap_iter  operator--(int) _NOEXCEPT
+    _LIBCPP_INLINE_VISIBILITY __wrap_iter  operator--(int) _NOEXCEPT_DEBUG
         {__wrap_iter __tmp(*this); --(*this); return __tmp;}
-    _LIBCPP_INLINE_VISIBILITY __wrap_iter  operator+ (difference_type __n) const _NOEXCEPT
+    _LIBCPP_INLINE_VISIBILITY __wrap_iter  operator+ (difference_type __n) const _NOEXCEPT_DEBUG
         {__wrap_iter __w(*this); __w += __n; return __w;}
-    _LIBCPP_INLINE_VISIBILITY __wrap_iter& operator+=(difference_type __n) _NOEXCEPT
+    _LIBCPP_INLINE_VISIBILITY __wrap_iter& operator+=(difference_type __n) _NOEXCEPT_DEBUG
     {
 #if _LIBCPP_DEBUG_LEVEL >= 2
         _LIBCPP_ASSERT(__get_const_db()->__addable(this, __n),
@@ -1320,11 +1356,11 @@ public:
         __i += __n;
         return *this;
     }
-    _LIBCPP_INLINE_VISIBILITY __wrap_iter  operator- (difference_type __n) const _NOEXCEPT
+    _LIBCPP_INLINE_VISIBILITY __wrap_iter  operator- (difference_type __n) const _NOEXCEPT_DEBUG
         {return *this + (-__n);}
-    _LIBCPP_INLINE_VISIBILITY __wrap_iter& operator-=(difference_type __n) _NOEXCEPT
+    _LIBCPP_INLINE_VISIBILITY __wrap_iter& operator-=(difference_type __n) _NOEXCEPT_DEBUG
         {*this += -__n; return *this;}
-    _LIBCPP_INLINE_VISIBILITY reference        operator[](difference_type __n) const _NOEXCEPT
+    _LIBCPP_INLINE_VISIBILITY reference        operator[](difference_type __n) const _NOEXCEPT_DEBUG
     {
 #if _LIBCPP_DEBUG_LEVEL >= 2
         _LIBCPP_ASSERT(__get_const_db()->__subscriptable(this, __n),
@@ -1333,7 +1369,7 @@ public:
         return __i[__n];
     }
 
-    _LIBCPP_INLINE_VISIBILITY iterator_type base() const _NOEXCEPT {return __i;}
+    _LIBCPP_INLINE_VISIBILITY iterator_type base() const _NOEXCEPT_DEBUG {return __i;}
 
 private:
 #if _LIBCPP_DEBUG_LEVEL >= 2
@@ -1342,66 +1378,67 @@ private:
         __get_db()->__insert_ic(this, __p);
     }
 #else
-    _LIBCPP_INLINE_VISIBILITY __wrap_iter(iterator_type __x) _NOEXCEPT : __i(__x) {}
+    _LIBCPP_INLINE_VISIBILITY __wrap_iter(iterator_type __x) _NOEXCEPT_DEBUG : __i(__x) {}
 #endif
 
     template <class _Up> friend class __wrap_iter;
     template <class _CharT, class _Traits, class _Alloc> friend class basic_string;
-    template <class _Tp, class _Alloc> friend class _LIBCPP_TYPE_VIS_ONLY vector;
+    template <class _Tp, class _Alloc> friend class _LIBCPP_TEMPLATE_VIS vector;
 
     template <class _Iter1, class _Iter2>
     friend
     bool
-    operator==(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
+    operator==(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT_DEBUG;
 
     template <class _Iter1, class _Iter2>
     friend
     bool
-    operator<(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
+    operator<(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT_DEBUG;
 
     template <class _Iter1, class _Iter2>
     friend
     bool
-    operator!=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
+    operator!=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT_DEBUG;
 
     template <class _Iter1, class _Iter2>
     friend
     bool
-    operator>(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
+    operator>(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT_DEBUG;
 
     template <class _Iter1, class _Iter2>
     friend
     bool
-    operator>=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
+    operator>=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT_DEBUG;
 
     template <class _Iter1, class _Iter2>
     friend
     bool
-    operator<=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
+    operator<=(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT_DEBUG;
 
 #ifndef _LIBCPP_CXX03_LANG
     template <class _Iter1, class _Iter2>
     friend
     auto
-    operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
+    operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT_DEBUG
     -> decltype(__x.base() - __y.base());
 #else
     template <class _Iter1, class _Iter2>
     friend
     typename __wrap_iter<_Iter1>::difference_type
-    operator-(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT;
+    operator-(const __wrap_iter<_Iter1>&, const __wrap_iter<_Iter2>&) _NOEXCEPT_DEBUG;
 #endif
 
     template <class _Iter1>
     friend
     __wrap_iter<_Iter1>
-    operator+(typename __wrap_iter<_Iter1>::difference_type, __wrap_iter<_Iter1>) _NOEXCEPT;
+    operator+(typename __wrap_iter<_Iter1>::difference_type, __wrap_iter<_Iter1>) _NOEXCEPT_DEBUG;
 
     template <class _Ip, class _Op> friend _Op copy(_Ip, _Ip, _Op);
     template <class _B1, class _B2> friend _B2 copy_backward(_B1, _B1, _B2);
     template <class _Ip, class _Op> friend _Op move(_Ip, _Ip, _Op);
     template <class _B1, class _B2> friend _B2 move_backward(_B1, _B1, _B2);
 
+#if _LIBCPP_DEBUG_LEVEL < 2
     template <class _Tp>
     friend
     typename enable_if
@@ -1410,12 +1447,22 @@ private:
         _Tp*
     >::type
     __unwrap_iter(__wrap_iter<_Tp*>);
+#else
+  template <class _Tp>
+  inline _LIBCPP_INLINE_VISIBILITY
+  typename enable_if
+  <
+      is_trivially_copy_assignable<_Tp>::value,
+      __wrap_iter<_Tp*>
+  >::type
+  __unwrap_iter(__wrap_iter<_Tp*> __i);
+#endif
 };
 
 template <class _Iter1, class _Iter2>
 inline _LIBCPP_INLINE_VISIBILITY
 bool
-operator==(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
+operator==(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT_DEBUG
 {
     return __x.base() == __y.base();
 }
@@ -1423,7 +1470,7 @@ operator==(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEX
 template <class _Iter1, class _Iter2>
 inline _LIBCPP_INLINE_VISIBILITY
 bool
-operator<(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
+operator<(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT_DEBUG
 {
 #if _LIBCPP_DEBUG_LEVEL >= 2
     _LIBCPP_ASSERT(__get_const_db()->__less_than_comparable(&__x, &__y),
@@ -1435,7 +1482,7 @@ operator<(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXC
 template <class _Iter1, class _Iter2>
 inline _LIBCPP_INLINE_VISIBILITY
 bool
-operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
+operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT_DEBUG
 {
     return !(__x == __y);
 }
@@ -1443,7 +1490,7 @@ operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEX
 template <class _Iter1, class _Iter2>
 inline _LIBCPP_INLINE_VISIBILITY
 bool
-operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
+operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT_DEBUG
 {
     return __y < __x;
 }
@@ -1451,7 +1498,7 @@ operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXC
 template <class _Iter1, class _Iter2>
 inline _LIBCPP_INLINE_VISIBILITY
 bool
-operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
+operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT_DEBUG
 {
     return !(__x < __y);
 }
@@ -1459,7 +1506,7 @@ operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEX
 template <class _Iter1, class _Iter2>
 inline _LIBCPP_INLINE_VISIBILITY
 bool
-operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
+operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT_DEBUG
 {
     return !(__y < __x);
 }
@@ -1467,7 +1514,7 @@ operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEX
 template <class _Iter1>
 inline _LIBCPP_INLINE_VISIBILITY
 bool
-operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
+operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT_DEBUG
 {
     return !(__x == __y);
 }
@@ -1475,7 +1522,7 @@ operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEX
 template <class _Iter1>
 inline _LIBCPP_INLINE_VISIBILITY
 bool
-operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
+operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT_DEBUG
 {
     return __y < __x;
 }
@@ -1483,7 +1530,7 @@ operator>(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXC
 template <class _Iter1>
 inline _LIBCPP_INLINE_VISIBILITY
 bool
-operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
+operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT_DEBUG
 {
     return !(__x < __y);
 }
@@ -1491,7 +1538,7 @@ operator>=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEX
 template <class _Iter1>
 inline _LIBCPP_INLINE_VISIBILITY
 bool
-operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
+operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT_DEBUG
 {
     return !(__y < __x);
 }
@@ -1500,7 +1547,7 @@ operator<=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEX
 template <class _Iter1, class _Iter2>
 inline _LIBCPP_INLINE_VISIBILITY
 auto
-operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
+operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT_DEBUG
 -> decltype(__x.base() - __y.base())
 {
 #if _LIBCPP_DEBUG_LEVEL >= 2
@@ -1513,7 +1560,7 @@ operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXC
 template <class _Iter1, class _Iter2>
 inline _LIBCPP_INLINE_VISIBILITY
 typename __wrap_iter<_Iter1>::difference_type
-operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
+operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT_DEBUG
 {
 #if _LIBCPP_DEBUG_LEVEL >= 2
     _LIBCPP_ASSERT(__get_const_db()->__less_than_comparable(&__x, &__y),
@@ -1527,7 +1574,7 @@ template <class _Iter>
 inline _LIBCPP_INLINE_VISIBILITY
 __wrap_iter<_Iter>
 operator+(typename __wrap_iter<_Iter>::difference_type __n,
-          __wrap_iter<_Iter> __x) _NOEXCEPT
+          __wrap_iter<_Iter> __x) _NOEXCEPT_DEBUG
 {
     __x += __n;
     return __x;
@@ -1535,19 +1582,19 @@ operator+(typename __wrap_iter<_Iter>::difference_type __n,
 
 template <class _Iter>
 struct __libcpp_is_trivial_iterator
-	: public _LIBCPP_BOOL_CONSTANT(is_pointer<_Iter>::value) {};
-	
+    : public _LIBCPP_BOOL_CONSTANT(is_pointer<_Iter>::value) {};
+    
 template <class _Iter>
 struct __libcpp_is_trivial_iterator<move_iterator<_Iter> >
-	: public _LIBCPP_BOOL_CONSTANT(__libcpp_is_trivial_iterator<_Iter>::value) {};
+    : public _LIBCPP_BOOL_CONSTANT(__libcpp_is_trivial_iterator<_Iter>::value) {};
 
 template <class _Iter>
 struct __libcpp_is_trivial_iterator<reverse_iterator<_Iter> >
-	: public _LIBCPP_BOOL_CONSTANT(__libcpp_is_trivial_iterator<_Iter>::value) {};
+    : public _LIBCPP_BOOL_CONSTANT(__libcpp_is_trivial_iterator<_Iter>::value) {};
 
 template <class _Iter>
 struct __libcpp_is_trivial_iterator<__wrap_iter<_Iter> >
-	: public _LIBCPP_BOOL_CONSTANT(__libcpp_is_trivial_iterator<_Iter>::value) {};
+    : public _LIBCPP_BOOL_CONSTANT(__libcpp_is_trivial_iterator<_Iter>::value) {};
 
 
 template <class _Tp, size_t _Np>
@@ -1566,10 +1613,10 @@ end(_Tp (&__array)[_Np])
     return __array + _Np;
 }
 
-#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_TRAILING_RETURN)
+#if !defined(_LIBCPP_CXX03_LANG)
 
 template <class _Cp>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 auto
 begin(_Cp& __c) -> decltype(__c.begin())
 {
@@ -1577,7 +1624,7 @@ begin(_Cp& __c) -> decltype(__c.begin())
 }
 
 template <class _Cp>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 auto
 begin(const _Cp& __c) -> decltype(__c.begin())
 {
@@ -1585,7 +1632,7 @@ begin(const _Cp& __c) -> decltype(__c.begin())
 }
 
 template <class _Cp>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 auto
 end(_Cp& __c) -> decltype(__c.end())
 {
@@ -1593,7 +1640,7 @@ end(_Cp& __c) -> decltype(__c.end())
 }
 
 template <class _Cp>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 auto
 end(const _Cp& __c) -> decltype(__c.end())
 {
@@ -1603,28 +1650,28 @@ end(const _Cp& __c) -> decltype(__c.end())
 #if _LIBCPP_STD_VER > 11
 
 template <class _Tp, size_t _Np>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 reverse_iterator<_Tp*> rbegin(_Tp (&__array)[_Np])
 {
     return reverse_iterator<_Tp*>(__array + _Np);
 }
 
 template <class _Tp, size_t _Np>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 reverse_iterator<_Tp*> rend(_Tp (&__array)[_Np])
 {
     return reverse_iterator<_Tp*>(__array);
 }
 
 template <class _Ep>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 reverse_iterator<const _Ep*> rbegin(initializer_list<_Ep> __il)
 {
     return reverse_iterator<const _Ep*>(__il.end());
 }
 
 template <class _Ep>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 reverse_iterator<const _Ep*> rend(initializer_list<_Ep> __il)
 {
     return reverse_iterator<const _Ep*>(__il.begin());
@@ -1645,42 +1692,42 @@ auto cend(const _Cp& __c) -> decltype(_VSTD::end(__c))
 }
 
 template <class _Cp>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 auto rbegin(_Cp& __c) -> decltype(__c.rbegin())
 {
     return __c.rbegin();
 }
 
 template <class _Cp>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 auto rbegin(const _Cp& __c) -> decltype(__c.rbegin())
 {
     return __c.rbegin();
 }
 
 template <class _Cp>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 auto rend(_Cp& __c) -> decltype(__c.rend())
 {
     return __c.rend();
 }
 
 template <class _Cp>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 auto rend(const _Cp& __c) -> decltype(__c.rend())
 {
     return __c.rend();
 }
 
 template <class _Cp>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 auto crbegin(const _Cp& __c) -> decltype(_VSTD::rbegin(__c))
 {
     return _VSTD::rbegin(__c);
 }
 
 template <class _Cp>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
 auto crend(const _Cp& __c) -> decltype(_VSTD::rend(__c))
 {
     return _VSTD::rend(__c);
@@ -1689,7 +1736,7 @@ auto crend(const _Cp& __c) -> decltype(_VSTD::rend(__c))
 #endif
 
 
-#else  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_TRAILING_RETURN)
+#else  // defined(_LIBCPP_CXX03_LANG)
 
 template <class _Cp>
 inline _LIBCPP_INLINE_VISIBILITY
@@ -1723,20 +1770,20 @@ end(const _Cp& __c)
     return __c.end();
 }
 
-#endif  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_TRAILING_RETURN)
+#endif  // !defined(_LIBCPP_CXX03_LANG)
 
 #if _LIBCPP_STD_VER > 14
 template <class _Cont>
 constexpr auto size(const _Cont& __c) -> decltype(__c.size()) { return __c.size(); }
 
 template <class _Tp, size_t _Sz>
-constexpr size_t size(const _Tp (&__array)[_Sz]) noexcept { return _Sz; }
+constexpr size_t size(const _Tp (&)[_Sz]) noexcept { return _Sz; }
 
 template <class _Cont>
 constexpr auto empty(const _Cont& __c) -> decltype(__c.empty()) { return __c.empty(); }
 
 template <class _Tp, size_t _Sz>
-constexpr bool empty(const _Tp (&__array)[_Sz]) noexcept { return false; }
+constexpr bool empty(const _Tp (&)[_Sz]) noexcept { return false; }
 
 template <class _Ep>
 constexpr bool empty(initializer_list<_Ep> __il) noexcept { return __il.size() == 0; }