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, 267 insertions, 283 deletions

diff --git a/contrib/libc++/include/__hash_table b/contrib/libc++/include/__hash_table
index 08bc519..e082e6c 100644
--- a/contrib/libc++/include/__hash_table
+++ b/contrib/libc++/include/__hash_table
@@ -20,7 +20,6 @@
 #include <utility>
 
 #include <__undef_min_max>
-#include <__undef___deallocate>
 
 #include <__debug>
 
@@ -59,9 +58,38 @@ size_t __next_prime(size_t __n);
 template <class _NodePtr>
 struct __hash_node_base
 {
+    typedef typename pointer_traits<_NodePtr>::element_type __node_type;
     typedef __hash_node_base __first_node;
+    typedef typename __rebind_pointer<_NodePtr, __first_node>::type __node_base_pointer;
+    typedef _NodePtr __node_pointer;
+
+#if defined(_LIBCPP_ABI_FIX_UNORDERED_NODE_POINTER_UB)
+  typedef __node_base_pointer __next_pointer;
+#else
+  typedef typename conditional<
+      is_pointer<__node_pointer>::value,
+      __node_base_pointer,
+      __node_pointer>::type   __next_pointer;
+#endif
+
+    __next_pointer    __next_;
+
+    _LIBCPP_INLINE_VISIBILITY
+    __next_pointer __ptr() _NOEXCEPT {
+        return static_cast<__next_pointer>(
+            pointer_traits<__node_base_pointer>::pointer_to(*this));
+    }
 
-    _NodePtr    __next_;
+    _LIBCPP_INLINE_VISIBILITY
+    __node_pointer __upcast() _NOEXCEPT {
+        return static_cast<__node_pointer>(
+            pointer_traits<__node_base_pointer>::pointer_to(*this));
+    }
+
+    _LIBCPP_INLINE_VISIBILITY
+    size_t __hash() const _NOEXCEPT {
+        return static_cast<__node_type const&>(*this).__hash_;
+    }
 
     _LIBCPP_INLINE_VISIBILITY __hash_node_base() _NOEXCEPT : __next_(nullptr) {}
 };
@@ -75,7 +103,7 @@ struct __hash_node
 {
     typedef _Tp __node_value_type;
 
-    size_t     __hash_;
+    size_t            __hash_;
     __node_value_type __value_;
 };
 
@@ -104,12 +132,12 @@ __next_hash_pow2(size_t __n)
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc> class __hash_table;
 
-template <class _NodePtr>      class _LIBCPP_TYPE_VIS_ONLY __hash_iterator;
-template <class _ConstNodePtr> class _LIBCPP_TYPE_VIS_ONLY __hash_const_iterator;
-template <class _NodePtr>      class _LIBCPP_TYPE_VIS_ONLY __hash_local_iterator;
-template <class _ConstNodePtr> class _LIBCPP_TYPE_VIS_ONLY __hash_const_local_iterator;
-template <class _HashIterator> class _LIBCPP_TYPE_VIS_ONLY __hash_map_iterator;
-template <class _HashIterator> class _LIBCPP_TYPE_VIS_ONLY __hash_map_const_iterator;
+template <class _NodePtr>      class _LIBCPP_TEMPLATE_VIS __hash_iterator;
+template <class _ConstNodePtr> class _LIBCPP_TEMPLATE_VIS __hash_const_iterator;
+template <class _NodePtr>      class _LIBCPP_TEMPLATE_VIS __hash_local_iterator;
+template <class _ConstNodePtr> class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator;
+template <class _HashIterator> class _LIBCPP_TEMPLATE_VIS __hash_map_iterator;
+template <class _HashIterator> class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator;
 
 template <class _Tp>
 struct __hash_key_value_types {
@@ -219,11 +247,14 @@ public:
   typedef typename __rebind_pointer<_NodePtr, __node_base_type>::type
                                                              __node_base_pointer;
 
+  typedef typename __node_base_type::__next_pointer          __next_pointer;
+
   typedef _Tp                                                 __node_value_type;
   typedef typename __rebind_pointer<_VoidPtr, __node_value_type>::type
                                                       __node_value_type_pointer;
   typedef typename __rebind_pointer<_VoidPtr, const __node_value_type>::type
                                                 __const_node_value_type_pointer;
+
 private:
     static_assert(!is_const<__node_type>::value,
                 "_NodePtr should never be a pointer to const");
@@ -233,8 +264,6 @@ private:
                           _NodePtr>::value), "_VoidPtr does not rebind to _NodePtr.");
 };
 
-
-
 template <class _HashIterator>
 struct __hash_node_types_from_iterator;
 template <class _NodePtr>
@@ -255,12 +284,13 @@ struct __make_hash_node_types {
 };
 
 template <class _NodePtr>
-class _LIBCPP_TYPE_VIS_ONLY __hash_iterator
+class _LIBCPP_TEMPLATE_VIS __hash_iterator
 {
     typedef __hash_node_types<_NodePtr> _NodeTypes;
-    typedef _NodePtr                    __node_pointer;
+    typedef _NodePtr                            __node_pointer;
+    typedef typename _NodeTypes::__next_pointer __next_pointer;
 
-    __node_pointer            __node_;
+    __next_pointer            __node_;
 
 public:
     typedef forward_iterator_tag                           iterator_category;
@@ -269,18 +299,11 @@ public:
     typedef value_type&                                    reference;
     typedef typename _NodeTypes::__node_value_type_pointer pointer;
 
-    _LIBCPP_INLINE_VISIBILITY __hash_iterator() _NOEXCEPT
-#if _LIBCPP_STD_VER > 11
-    : __node_(nullptr)
-#endif
-    {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-        __get_db()->__insert_i(this);
-#endif
+    _LIBCPP_INLINE_VISIBILITY __hash_iterator() _NOEXCEPT : __node_(nullptr) {
+        _LIBCPP_DEBUG_MODE(__get_db()->__insert_i(this));
     }
 
 #if _LIBCPP_DEBUG_LEVEL >= 2
-
     _LIBCPP_INLINE_VISIBILITY
     __hash_iterator(const __hash_iterator& __i)
         : __node_(__i.__node_)
@@ -304,35 +327,26 @@ public:
         }
         return *this;
     }
-
 #endif  // _LIBCPP_DEBUG_LEVEL >= 2
 
     _LIBCPP_INLINE_VISIBILITY
-        reference operator*() const
-        {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-            _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
-                           "Attempted to dereference a non-dereferenceable unordered container iterator");
-#endif
-            return __node_->__value_;
-        }
+    reference operator*() const {
+        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
+                             "Attempted to dereference a non-dereferenceable unordered container iterator");
+        return __node_->__upcast()->__value_;
+    }
+
     _LIBCPP_INLINE_VISIBILITY
-        pointer operator->() const
-        {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-            _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
+    pointer operator->() const {
+        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
                            "Attempted to dereference a non-dereferenceable unordered container iterator");
-#endif
-            return pointer_traits<pointer>::pointer_to(__node_->__value_);
-        }
+        return pointer_traits<pointer>::pointer_to(__node_->__upcast()->__value_);
+    }
 
     _LIBCPP_INLINE_VISIBILITY
-    __hash_iterator& operator++()
-    {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-        _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
+    __hash_iterator& operator++() {
+        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
                        "Attempted to increment non-incrementable unordered container iterator");
-#endif
         __node_ = __node_->__next_;
         return *this;
     }
@@ -357,33 +371,33 @@ public:
 private:
 #if _LIBCPP_DEBUG_LEVEL >= 2
     _LIBCPP_INLINE_VISIBILITY
-    __hash_iterator(__node_pointer __node, const void* __c) _NOEXCEPT
+    __hash_iterator(__next_pointer __node, const void* __c) _NOEXCEPT
         : __node_(__node)
         {
             __get_db()->__insert_ic(this, __c);
         }
 #else
     _LIBCPP_INLINE_VISIBILITY
-    __hash_iterator(__node_pointer __node) _NOEXCEPT
+    __hash_iterator(__next_pointer __node) _NOEXCEPT
         : __node_(__node)
         {}
 #endif
-
     template <class, class, class, class> friend class __hash_table;
-    template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_const_iterator;
-    template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_map_iterator;
-    template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_map;
-    template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_multimap;
+    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_const_iterator;
+    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_map_iterator;
+    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_map;
+    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
 };
 
 template <class _NodePtr>
-class _LIBCPP_TYPE_VIS_ONLY __hash_const_iterator
+class _LIBCPP_TEMPLATE_VIS __hash_const_iterator
 {
     static_assert(!is_const<typename pointer_traits<_NodePtr>::element_type>::value, "");
     typedef __hash_node_types<_NodePtr> _NodeTypes;
-    typedef _NodePtr __node_pointer;
+    typedef _NodePtr                            __node_pointer;
+    typedef typename _NodeTypes::__next_pointer __next_pointer;
 
-    __node_pointer __node_;
+    __next_pointer __node_;
 
 public:
     typedef __hash_iterator<_NodePtr> __non_const_iterator;
@@ -395,26 +409,18 @@ public:
     typedef typename _NodeTypes::__const_node_value_type_pointer pointer;
 
 
-    _LIBCPP_INLINE_VISIBILITY __hash_const_iterator() _NOEXCEPT
-#if _LIBCPP_STD_VER > 11
-    : __node_(nullptr)
-#endif
-    {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-        __get_db()->__insert_i(this);
-#endif
+    _LIBCPP_INLINE_VISIBILITY __hash_const_iterator() _NOEXCEPT : __node_(nullptr) {
+        _LIBCPP_DEBUG_MODE(__get_db()->__insert_i(this));
     }
+
     _LIBCPP_INLINE_VISIBILITY 
     __hash_const_iterator(const __non_const_iterator& __x) _NOEXCEPT
         : __node_(__x.__node_)
     {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-        __get_db()->__iterator_copy(this, &__x);
-#endif
+        _LIBCPP_DEBUG_MODE(__get_db()->__iterator_copy(this, &__x));
     }
 
 #if _LIBCPP_DEBUG_LEVEL >= 2
-
     _LIBCPP_INLINE_VISIBILITY
     __hash_const_iterator(const __hash_const_iterator& __i)
         : __node_(__i.__node_)
@@ -438,35 +444,25 @@ public:
         }
         return *this;
     }
-
 #endif  // _LIBCPP_DEBUG_LEVEL >= 2
 
     _LIBCPP_INLINE_VISIBILITY
-        reference operator*() const
-        {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-            _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
+    reference operator*() const {
+        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
                            "Attempted to dereference a non-dereferenceable unordered container const_iterator");
-#endif
-            return __node_->__value_;
-        }
+        return __node_->__upcast()->__value_;
+    }
     _LIBCPP_INLINE_VISIBILITY
-        pointer operator->() const
-        {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-            _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
+    pointer operator->() const {
+        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
                            "Attempted to dereference a non-dereferenceable unordered container const_iterator");
-#endif
-            return pointer_traits<pointer>::pointer_to(__node_->__value_);
-        }
+        return pointer_traits<pointer>::pointer_to(__node_->__upcast()->__value_);
+    }
 
     _LIBCPP_INLINE_VISIBILITY
-    __hash_const_iterator& operator++()
-    {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-        _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
-                       "Attempted to increment non-incrementable unordered container const_iterator");
-#endif
+    __hash_const_iterator& operator++() {
+        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
+                             "Attempted to increment non-incrementable unordered container const_iterator");
         __node_ = __node_->__next_;
         return *this;
     }
@@ -491,31 +487,31 @@ public:
 private:
 #if _LIBCPP_DEBUG_LEVEL >= 2
     _LIBCPP_INLINE_VISIBILITY
-    __hash_const_iterator(__node_pointer __node, const void* __c) _NOEXCEPT
+    __hash_const_iterator(__next_pointer __node, const void* __c) _NOEXCEPT
         : __node_(__node)
         {
             __get_db()->__insert_ic(this, __c);
         }
 #else
     _LIBCPP_INLINE_VISIBILITY
-    __hash_const_iterator(__node_pointer __node) _NOEXCEPT
+    __hash_const_iterator(__next_pointer __node) _NOEXCEPT
         : __node_(__node)
         {}
 #endif
-
     template <class, class, class, class> friend class __hash_table;
-    template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_map_const_iterator;
-    template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_map;
-    template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_multimap;
+    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator;
+    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_map;
+    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
 };
 
 template <class _NodePtr>
-class _LIBCPP_TYPE_VIS_ONLY __hash_local_iterator
+class _LIBCPP_TEMPLATE_VIS __hash_local_iterator
 {
     typedef __hash_node_types<_NodePtr> _NodeTypes;
-    typedef _NodePtr                    __node_pointer;
+    typedef _NodePtr                            __node_pointer;
+    typedef typename _NodeTypes::__next_pointer __next_pointer;
 
-    __node_pointer         __node_;
+    __next_pointer         __node_;
     size_t                 __bucket_;
     size_t                 __bucket_count_;
 
@@ -526,15 +522,11 @@ public:
     typedef value_type&                                         reference;
     typedef typename _NodeTypes::__node_value_type_pointer      pointer;
 
-    _LIBCPP_INLINE_VISIBILITY __hash_local_iterator() _NOEXCEPT
-    {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-        __get_db()->__insert_i(this);
-#endif
+    _LIBCPP_INLINE_VISIBILITY __hash_local_iterator() _NOEXCEPT : __node_(nullptr) {
+        _LIBCPP_DEBUG_MODE(__get_db()->__insert_i(this));
     }
 
 #if _LIBCPP_DEBUG_LEVEL >= 2
-
     _LIBCPP_INLINE_VISIBILITY
     __hash_local_iterator(const __hash_local_iterator& __i)
         : __node_(__i.__node_),
@@ -562,37 +554,28 @@ public:
         }
         return *this;
     }
-
 #endif  // _LIBCPP_DEBUG_LEVEL >= 2
 
     _LIBCPP_INLINE_VISIBILITY
-        reference operator*() const
-        {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-            _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
+    reference operator*() const {
+        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
                            "Attempted to dereference a non-dereferenceable unordered container local_iterator");
-#endif
-            return __node_->__value_;
-        }
+        return __node_->__upcast()->__value_;
+    }
+
     _LIBCPP_INLINE_VISIBILITY
-        pointer operator->() const
-        {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-            _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
-                           "Attempted to dereference a non-dereferenceable unordered container local_iterator");
-#endif
-            return pointer_traits<pointer>::pointer_to(__node_->__value_);
-        }
+    pointer operator->() const {
+        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
+                             "Attempted to dereference a non-dereferenceable unordered container local_iterator");
+        return pointer_traits<pointer>::pointer_to(__node_->__upcast()->__value_);
+    }
 
     _LIBCPP_INLINE_VISIBILITY
-    __hash_local_iterator& operator++()
-    {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-        _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
+    __hash_local_iterator& operator++() {
+        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
                        "Attempted to increment non-incrementable unordered container local_iterator");
-#endif
         __node_ = __node_->__next_;
-        if (__node_ != nullptr && __constrain_hash(__node_->__hash_, __bucket_count_) != __bucket_)
+        if (__node_ != nullptr && __constrain_hash(__node_->__hash(), __bucket_count_) != __bucket_)
             __node_ = nullptr;
         return *this;
     }
@@ -617,7 +600,7 @@ public:
 private:
 #if _LIBCPP_DEBUG_LEVEL >= 2
     _LIBCPP_INLINE_VISIBILITY
-    __hash_local_iterator(__node_pointer __node, size_t __bucket,
+    __hash_local_iterator(__next_pointer __node, size_t __bucket,
                           size_t __bucket_count, const void* __c) _NOEXCEPT
         : __node_(__node),
           __bucket_(__bucket),
@@ -629,7 +612,7 @@ private:
         }
 #else
     _LIBCPP_INLINE_VISIBILITY
-    __hash_local_iterator(__node_pointer __node, size_t __bucket,
+    __hash_local_iterator(__next_pointer __node, size_t __bucket,
                           size_t __bucket_count) _NOEXCEPT
         : __node_(__node),
           __bucket_(__bucket),
@@ -640,17 +623,18 @@ private:
         }
 #endif
     template <class, class, class, class> friend class __hash_table;
-    template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_const_local_iterator;
-    template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_map_iterator;
+    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator;
+    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_map_iterator;
 };
 
 template <class _ConstNodePtr>
-class _LIBCPP_TYPE_VIS_ONLY __hash_const_local_iterator
+class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator
 {
     typedef __hash_node_types<_ConstNodePtr> _NodeTypes;
-    typedef _ConstNodePtr                    __node_pointer;
+    typedef _ConstNodePtr                       __node_pointer;
+    typedef typename _NodeTypes::__next_pointer __next_pointer;
 
-    __node_pointer         __node_;
+    __next_pointer         __node_;
     size_t                 __bucket_;
     size_t                 __bucket_count_;
 
@@ -670,11 +654,8 @@ public:
     typedef typename _NodeTypes::__const_node_value_type_pointer pointer;
 
 
-    _LIBCPP_INLINE_VISIBILITY __hash_const_local_iterator() _NOEXCEPT
-    {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-        __get_db()->__insert_i(this);
-#endif
+    _LIBCPP_INLINE_VISIBILITY __hash_const_local_iterator() _NOEXCEPT : __node_(nullptr) {
+        _LIBCPP_DEBUG_MODE(__get_db()->__insert_i(this));
     }
 
     _LIBCPP_INLINE_VISIBILITY
@@ -683,13 +664,10 @@ public:
           __bucket_(__x.__bucket_),
           __bucket_count_(__x.__bucket_count_)
     {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-        __get_db()->__iterator_copy(this, &__x);
-#endif
+        _LIBCPP_DEBUG_MODE(__get_db()->__iterator_copy(this, &__x));
     }
 
 #if _LIBCPP_DEBUG_LEVEL >= 2
-
     _LIBCPP_INLINE_VISIBILITY
     __hash_const_local_iterator(const __hash_const_local_iterator& __i)
         : __node_(__i.__node_),
@@ -717,37 +695,28 @@ public:
         }
         return *this;
     }
-
 #endif  // _LIBCPP_DEBUG_LEVEL >= 2
 
     _LIBCPP_INLINE_VISIBILITY
-        reference operator*() const
-        {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-            _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
+    reference operator*() const {
+        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
                            "Attempted to dereference a non-dereferenceable unordered container const_local_iterator");
-#endif
-            return __node_->__value_;
-        }
+        return __node_->__upcast()->__value_;
+    }
+
     _LIBCPP_INLINE_VISIBILITY
-        pointer operator->() const
-        {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-            _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
+    pointer operator->() const {
+        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
                            "Attempted to dereference a non-dereferenceable unordered container const_local_iterator");
-#endif
-            return pointer_traits<pointer>::pointer_to(__node_->__value_);
-        }
+        return pointer_traits<pointer>::pointer_to(__node_->__upcast()->__value_);
+    }
 
     _LIBCPP_INLINE_VISIBILITY
-    __hash_const_local_iterator& operator++()
-    {
-#if _LIBCPP_DEBUG_LEVEL >= 2
-        _LIBCPP_ASSERT(__get_const_db()->__dereferenceable(this),
+    __hash_const_local_iterator& operator++() {
+        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
                        "Attempted to increment non-incrementable unordered container const_local_iterator");
-#endif
         __node_ = __node_->__next_;
-        if (__node_ != nullptr && __constrain_hash(__node_->__hash_, __bucket_count_) != __bucket_)
+        if (__node_ != nullptr && __constrain_hash(__node_->__hash(), __bucket_count_) != __bucket_)
             __node_ = nullptr;
         return *this;
     }
@@ -772,7 +741,7 @@ public:
 private:
 #if _LIBCPP_DEBUG_LEVEL >= 2
     _LIBCPP_INLINE_VISIBILITY
-    __hash_const_local_iterator(__node_pointer __node, size_t __bucket,
+    __hash_const_local_iterator(__next_pointer __node, size_t __bucket,
                                 size_t __bucket_count, const void* __c) _NOEXCEPT
         : __node_(__node),
           __bucket_(__bucket),
@@ -784,7 +753,7 @@ private:
         }
 #else
     _LIBCPP_INLINE_VISIBILITY
-    __hash_const_local_iterator(__node_pointer __node, size_t __bucket,
+    __hash_const_local_iterator(__next_pointer __node, size_t __bucket,
                                 size_t __bucket_count) _NOEXCEPT
         : __node_(__node),
           __bucket_(__bucket),
@@ -795,7 +764,7 @@ private:
         }
 #endif
     template <class, class, class, class> friend class __hash_table;
-    template <class> friend class _LIBCPP_TYPE_VIS_ONLY __hash_map_const_iterator;
+    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator;
 };
 
 template <class _Alloc>
@@ -927,6 +896,7 @@ public:
     typedef typename _NodeTypes::__node_pointer      __node_const_pointer;
     typedef typename _NodeTypes::__node_base_type    __first_node;
     typedef typename _NodeTypes::__node_base_pointer __node_base_pointer;
+    typedef typename _NodeTypes::__next_pointer      __next_pointer;
 
 private:
     // check for sane allocator pointer rebinding semantics. Rebinding the
@@ -942,11 +912,11 @@ private:
 
 private:
 
-    typedef typename __rebind_alloc_helper<__node_traits, __node_pointer>::type __pointer_allocator;
+    typedef typename __rebind_alloc_helper<__node_traits, __next_pointer>::type __pointer_allocator;
     typedef __bucket_list_deallocator<__pointer_allocator> __bucket_list_deleter;
-    typedef unique_ptr<__node_pointer[], __bucket_list_deleter> __bucket_list;
+    typedef unique_ptr<__next_pointer[], __bucket_list_deleter> __bucket_list;
     typedef allocator_traits<__pointer_allocator>          __pointer_alloc_traits;
-    typedef typename __bucket_list_deleter::pointer __node_pointer_pointer;
+    typedef typename __bucket_list_deleter::pointer       __node_pointer_pointer;
 
     // --- Member data begin ---
     __bucket_list                                         __bucket_list_;
@@ -1033,8 +1003,10 @@ public:
     _LIBCPP_INLINE_VISIBILITY
     size_type max_size() const _NOEXCEPT
     {
-        return allocator_traits<__pointer_allocator>::max_size(
-            __bucket_list_.get_deleter().__alloc());
+        return std::min<size_type>(
+            __node_traits::max_size(__node_alloc()),
+            numeric_limits<difference_type >::max()
+        );
     }
 
     pair<iterator, bool> __node_insert_unique(__node_pointer __nd);
@@ -1129,6 +1101,7 @@ public:
 
 #else  // !defined(_LIBCPP_CXX03_LANG)
     template <class _Key, class _Args>
+    _LIBCPP_INLINE_VISIBILITY
     pair<iterator, bool> __emplace_unique_key_args(_Key const&, _Args& __args);
 
     iterator __insert_multi(const __container_value_type& __x);
@@ -1207,7 +1180,7 @@ public:
 
     void swap(__hash_table& __u)
 #if _LIBCPP_STD_VER <= 11
-        _NOEXCEPT_(
+        _NOEXCEPT_DEBUG_(
             __is_nothrow_swappable<hasher>::value && __is_nothrow_swappable<key_equal>::value
             && (!allocator_traits<__pointer_allocator>::propagate_on_container_swap::value
                   || __is_nothrow_swappable<__pointer_allocator>::value)
@@ -1215,12 +1188,12 @@ public:
                   || __is_nothrow_swappable<__node_allocator>::value)
             );
 #else
-     _NOEXCEPT_(__is_nothrow_swappable<hasher>::value && __is_nothrow_swappable<key_equal>::value);
+     _NOEXCEPT_DEBUG_(__is_nothrow_swappable<hasher>::value && __is_nothrow_swappable<key_equal>::value);
 #endif
 
     _LIBCPP_INLINE_VISIBILITY
     size_type max_bucket_count() const _NOEXCEPT
-        {return __pointer_alloc_traits::max_size(__bucket_list_.get_deleter().__alloc());}
+        {return max_size(); }
     size_type bucket_size(size_type __n) const;
     _LIBCPP_INLINE_VISIBILITY float load_factor() const _NOEXCEPT
     {
@@ -1347,11 +1320,11 @@ private:
         void __move_assign_alloc(__hash_table&, false_type) _NOEXCEPT {}
 #endif // _LIBCPP_CXX03_LANG
 
-    void __deallocate(__node_pointer __np) _NOEXCEPT;
-    __node_pointer __detach() _NOEXCEPT;
+    void __deallocate_node(__next_pointer __np) _NOEXCEPT;
+    __next_pointer __detach() _NOEXCEPT;
 
-    template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_map;
-    template <class, class, class, class, class> friend class _LIBCPP_TYPE_VIS_ONLY unordered_multimap;
+    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_map;
+    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
 };
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
@@ -1439,8 +1412,8 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(__hash_table&& __u)
 {
     if (size() > 0)
     {
-        __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash_, bucket_count())] =
-            static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
+        __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash(), bucket_count())] =
+            __p1_.first().__ptr();
         __u.__p1_.first().__next_ = nullptr;
         __u.size() = 0;
     }
@@ -1463,8 +1436,8 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__hash_table(__hash_table&& __u,
         {
             __p1_.first().__next_ = __u.__p1_.first().__next_;
             __u.__p1_.first().__next_ = nullptr;
-            __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash_, bucket_count())] =
-                static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
+            __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash(), bucket_count())] =
+                __p1_.first().__ptr();
             size() = __u.size();
             __u.size() = 0;
         }
@@ -1480,7 +1453,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::~__hash_table()
                  "Predicate must be copy-constructible.");
     static_assert((is_copy_constructible<hasher>::value),
                  "Hasher must be copy-constructible.");
-    __deallocate(__p1_.first().__next_);
+    __deallocate_node(__p1_.first().__next_);
 #if _LIBCPP_DEBUG_LEVEL >= 2
     __get_db()->__erase_c(this);
 #endif
@@ -1518,13 +1491,13 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::operator=(const __hash_table& __u)
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 void
-__hash_table<_Tp, _Hash, _Equal, _Alloc>::__deallocate(__node_pointer __np)
+__hash_table<_Tp, _Hash, _Equal, _Alloc>::__deallocate_node(__next_pointer __np)
     _NOEXCEPT
 {
     __node_allocator& __na = __node_alloc();
     while (__np != nullptr)
     {
-        __node_pointer __next = __np->__next_;
+        __next_pointer __next = __np->__next_;
 #if _LIBCPP_DEBUG_LEVEL >= 2
         __c_node* __c = __get_db()->__find_c_and_lock(this);
         for (__i_node** __p = __c->end_; __p != __c->beg_; )
@@ -1540,21 +1513,22 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__deallocate(__node_pointer __np)
         }
         __get_db()->unlock();
 #endif
-        __node_traits::destroy(__na, _NodeTypes::__get_ptr(__np->__value_));
-        __node_traits::deallocate(__na, __np, 1);
+        __node_pointer __real_np = __np->__upcast();
+        __node_traits::destroy(__na, _NodeTypes::__get_ptr(__real_np->__value_));
+        __node_traits::deallocate(__na, __real_np, 1);
         __np = __next;
     }
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
-typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_pointer
+typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__next_pointer
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::__detach() _NOEXCEPT
 {
     size_type __bc = bucket_count();
     for (size_type __i = 0; __i < __bc; ++__i)
         __bucket_list_[__i] = nullptr;
     size() = 0;
-    __node_pointer __cache = __p1_.first().__next_;
+    __next_pointer __cache = __p1_.first().__next_;
     __p1_.first().__next_ = nullptr;
     return __cache;
 }
@@ -1582,8 +1556,8 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__move_assign(
     __p1_.first().__next_ = __u.__p1_.first().__next_;
     if (size() > 0)
     {
-        __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash_, bucket_count())] =
-            static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
+        __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash(), bucket_count())] =
+            __p1_.first().__ptr();
         __u.__p1_.first().__next_ = nullptr;
         __u.size() = 0;
     }
@@ -1606,7 +1580,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__move_assign(
         max_load_factor() = __u.max_load_factor();
         if (bucket_count() != 0)
         {
-            __node_pointer __cache = __detach();
+            __next_pointer __cache = __detach();
 #ifndef _LIBCPP_NO_EXCEPTIONS
             try
             {
@@ -1614,20 +1588,21 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__move_assign(
                 const_iterator __i = __u.begin();
                 while (__cache != nullptr && __u.size() != 0)
                 {
-                    __cache->__value_ = _VSTD::move(__u.remove(__i++)->__value_);
-                    __node_pointer __next = __cache->__next_;
-                    __node_insert_multi(__cache);
+                    __cache->__upcast()->__value_ =
+                        _VSTD::move(__u.remove(__i++)->__value_);
+                    __next_pointer __next = __cache->__next_;
+                    __node_insert_multi(__cache->__upcast());
                     __cache = __next;
                 }
 #ifndef _LIBCPP_NO_EXCEPTIONS
             }
             catch (...)
             {
-                __deallocate(__cache);
+                __deallocate_node(__cache);
                 throw;
             }
 #endif  // _LIBCPP_NO_EXCEPTIONS
-            __deallocate(__cache);
+            __deallocate_node(__cache);
         }
         const_iterator __i = __u.begin();
         while (__u.size() != 0)
@@ -1669,27 +1644,27 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__assign_unique(_InputIterator __first
 
     if (bucket_count() != 0)
     {
-        __node_pointer __cache = __detach();
+        __next_pointer __cache = __detach();
 #ifndef _LIBCPP_NO_EXCEPTIONS
         try
         {
 #endif  // _LIBCPP_NO_EXCEPTIONS
             for (; __cache != nullptr && __first != __last; ++__first)
             {
-                __cache->__value_ = *__first;
-                __node_pointer __next = __cache->__next_;
-                __node_insert_unique(__cache);
+                __cache->__upcast()->__value_ = *__first;
+                __next_pointer __next = __cache->__next_;
+                __node_insert_unique(__cache->__upcast());
                 __cache = __next;
             }
 #ifndef _LIBCPP_NO_EXCEPTIONS
         }
         catch (...)
         {
-            __deallocate(__cache);
+            __deallocate_node(__cache);
             throw;
         }
 #endif  // _LIBCPP_NO_EXCEPTIONS
-        __deallocate(__cache);
+        __deallocate_node(__cache);
     }
     for (; __first != __last; ++__first)
         __insert_unique(*__first);
@@ -1709,27 +1684,27 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__assign_multi(_InputIterator __first,
                   " or the nodes value type");
     if (bucket_count() != 0)
     {
-        __node_pointer __cache = __detach();
+        __next_pointer __cache = __detach();
 #ifndef _LIBCPP_NO_EXCEPTIONS
         try
         {
 #endif  // _LIBCPP_NO_EXCEPTIONS
             for (; __cache != nullptr && __first != __last; ++__first)
             {
-                __cache->__value_ = *__first;
-                __node_pointer __next = __cache->__next_;
-                __node_insert_multi(__cache);
+                __cache->__upcast()->__value_ = *__first;
+                __next_pointer __next = __cache->__next_;
+                __node_insert_multi(__cache->__upcast());
                 __cache = __next;
             }
 #ifndef _LIBCPP_NO_EXCEPTIONS
         }
         catch (...)
         {
-            __deallocate(__cache);
+            __deallocate_node(__cache);
             throw;
         }
 #endif  // _LIBCPP_NO_EXCEPTIONS
-        __deallocate(__cache);
+        __deallocate_node(__cache);
     }
     for (; __first != __last; ++__first)
         __insert_multi(_NodeTypes::__get_value(*__first));
@@ -1789,7 +1764,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::clear() _NOEXCEPT
 {
     if (size() > 0)
     {
-        __deallocate(__p1_.first().__next_);
+        __deallocate_node(__p1_.first().__next_);
         __p1_.first().__next_ = nullptr;
         size_type __bc = bucket_count();
         for (size_type __i = 0; __i < __bc; ++__i)
@@ -1805,7 +1780,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_unique(__node_pointer __
     __nd->__hash_ = hash_function()(__nd->__value_);
     size_type __bc = bucket_count();
     bool __inserted = false;
-    __node_pointer __ndptr;
+    __next_pointer __ndptr;
     size_t __chash;
     if (__bc != 0)
     {
@@ -1814,10 +1789,10 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_unique(__node_pointer __
         if (__ndptr != nullptr)
         {
             for (__ndptr = __ndptr->__next_; __ndptr != nullptr &&
-                                             __constrain_hash(__ndptr->__hash_, __bc) == __chash;
+                                             __constrain_hash(__ndptr->__hash(), __bc) == __chash;
                                                      __ndptr = __ndptr->__next_)
             {
-                if (key_eq()(__ndptr->__value_, __nd->__value_))
+                if (key_eq()(__ndptr->__upcast()->__value_, __nd->__value_))
                     goto __done;
             }
         }
@@ -1831,23 +1806,23 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_unique(__node_pointer __
             __chash = __constrain_hash(__nd->__hash_, __bc);
         }
         // insert_after __bucket_list_[__chash], or __first_node if bucket is null
-        __node_pointer __pn = __bucket_list_[__chash];
+        __next_pointer __pn = __bucket_list_[__chash];
         if (__pn == nullptr)
         {
-            __pn = static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
+            __pn =__p1_.first().__ptr();
             __nd->__next_ = __pn->__next_;
-            __pn->__next_ = __nd;
+            __pn->__next_ = __nd->__ptr();
             // fix up __bucket_list_
             __bucket_list_[__chash] = __pn;
             if (__nd->__next_ != nullptr)
-                __bucket_list_[__constrain_hash(__nd->__next_->__hash_, __bc)] = __nd;
+                __bucket_list_[__constrain_hash(__nd->__next_->__hash(), __bc)] = __nd->__ptr();
         }
         else
         {
             __nd->__next_ = __pn->__next_;
-            __pn->__next_ = __nd;
+            __pn->__next_ = __nd->__ptr();
         }
-        __ndptr = __nd;
+        __ndptr = __nd->__ptr();
         // increment size
         ++size();
         __inserted = true;
@@ -1873,21 +1848,22 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi(__node_pointer __c
         __bc = bucket_count();
     }
     size_t __chash = __constrain_hash(__cp->__hash_, __bc);
-    __node_pointer __pn = __bucket_list_[__chash];
+    __next_pointer __pn = __bucket_list_[__chash];
     if (__pn == nullptr)
     {
-        __pn = static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
+        __pn =__p1_.first().__ptr();
         __cp->__next_ = __pn->__next_;
-        __pn->__next_ = __cp;
+        __pn->__next_ = __cp->__ptr();
         // fix up __bucket_list_
         __bucket_list_[__chash] = __pn;
         if (__cp->__next_ != nullptr)
-            __bucket_list_[__constrain_hash(__cp->__next_->__hash_, __bc)] = __cp;
+            __bucket_list_[__constrain_hash(__cp->__next_->__hash(), __bc)]
+                = __cp->__ptr();
     }
     else
     {
         for (bool __found = false; __pn->__next_ != nullptr &&
-                                   __constrain_hash(__pn->__next_->__hash_, __bc) == __chash;
+                                   __constrain_hash(__pn->__next_->__hash(), __bc) == __chash;
                                                            __pn = __pn->__next_)
         {
             //      __found    key_eq()     action
@@ -1895,8 +1871,8 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi(__node_pointer __c
             //      true        true        loop
             //      false       true        set __found to true
             //      true        false       break
-            if (__found != (__pn->__next_->__hash_ == __cp->__hash_ &&
-                            key_eq()(__pn->__next_->__value_, __cp->__value_)))
+            if (__found != (__pn->__next_->__hash() == __cp->__hash_ &&
+                            key_eq()(__pn->__next_->__upcast()->__value_, __cp->__value_)))
             {
                 if (!__found)
                     __found = true;
@@ -1905,19 +1881,19 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi(__node_pointer __c
             }
         }
         __cp->__next_ = __pn->__next_;
-        __pn->__next_ = __cp;
+        __pn->__next_ = __cp->__ptr();
         if (__cp->__next_ != nullptr)
         {
-            size_t __nhash = __constrain_hash(__cp->__next_->__hash_, __bc);
+            size_t __nhash = __constrain_hash(__cp->__next_->__hash(), __bc);
             if (__nhash != __chash)
-                __bucket_list_[__nhash] = __cp;
+                __bucket_list_[__nhash] = __cp->__ptr();
         }
     }
     ++size();
 #if _LIBCPP_DEBUG_LEVEL >= 2
-    return iterator(__cp, this);
+    return iterator(__cp->__ptr(), this);
 #else
-    return iterator(__cp);
+    return iterator(__cp->__ptr());
 #endif
 }
 
@@ -1933,8 +1909,8 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi(
 #endif
     if (__p != end() && key_eq()(*__p, __cp->__value_))
     {
-        __node_pointer __np = __p.__node_;
-        __cp->__hash_ = __np->__hash_;
+        __next_pointer __np = __p.__node_;
+        __cp->__hash_ = __np->__hash();
         size_type __bc = bucket_count();
         if (size()+1 > __bc * max_load_factor() || __bc == 0)
         {
@@ -1943,16 +1919,16 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi(
             __bc = bucket_count();
         }
         size_t __chash = __constrain_hash(__cp->__hash_, __bc);
-        __node_pointer __pp = __bucket_list_[__chash];
+        __next_pointer __pp = __bucket_list_[__chash];
         while (__pp->__next_ != __np)
             __pp = __pp->__next_;
         __cp->__next_ = __np;
-        __pp->__next_ = __cp;
+        __pp->__next_ = static_cast<__next_pointer>(__cp);
         ++size();
 #if _LIBCPP_DEBUG_LEVEL >= 2
-        return iterator(__cp, this);
+        return iterator(static_cast<__next_pointer>(__cp), this);
 #else
-        return iterator(__cp);
+        return iterator(static_cast<__next_pointer>(__cp));
 #endif
     }
     return __node_insert_multi(__cp);
@@ -1963,13 +1939,11 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi(
 #ifndef _LIBCPP_CXX03_LANG
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 template <class _Key, class ..._Args>
-_LIBCPP_INLINE_VISIBILITY
 pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator, bool>
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_unique_key_args(_Key const& __k, _Args&&... __args)
 #else
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 template <class _Key, class _Args>
-_LIBCPP_INLINE_VISIBILITY
 pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator, bool>
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_unique_key_args(_Key const& __k, _Args& __args)
 #endif
@@ -1978,7 +1952,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_unique_key_args(_Key const&
     size_t __hash = hash_function()(__k);
     size_type __bc = bucket_count();
     bool __inserted = false;
-    __node_pointer __nd;
+    __next_pointer __nd;
     size_t __chash;
     if (__bc != 0)
     {
@@ -1987,10 +1961,10 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_unique_key_args(_Key const&
         if (__nd != nullptr)
         {
             for (__nd = __nd->__next_; __nd != nullptr &&
-                                       __constrain_hash(__nd->__hash_, __bc) == __chash;
+                (__nd->__hash() == __hash || __constrain_hash(__nd->__hash(), __bc) == __chash);
                                                            __nd = __nd->__next_)
             {
-                if (key_eq()(__nd->__value_, __k))
+                if (key_eq()(__nd->__upcast()->__value_, __k))
                     goto __done;
             }
         }
@@ -2009,23 +1983,24 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_unique_key_args(_Key const&
             __chash = __constrain_hash(__hash, __bc);
         }
         // insert_after __bucket_list_[__chash], or __first_node if bucket is null
-        __node_pointer __pn = __bucket_list_[__chash];
+        __next_pointer __pn = __bucket_list_[__chash];
         if (__pn == nullptr)
         {
-            __pn = static_cast<__node_pointer>(static_cast<__void_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first())));
+            __pn = __p1_.first().__ptr();
             __h->__next_ = __pn->__next_;
-            __pn->__next_ = __h.get();
+            __pn->__next_ = __h.get()->__ptr();
             // fix up __bucket_list_
             __bucket_list_[__chash] = __pn;
             if (__h->__next_ != nullptr)
-                __bucket_list_[__constrain_hash(__h->__next_->__hash_, __bc)] = __h.get();
+                __bucket_list_[__constrain_hash(__h->__next_->__hash(), __bc)]
+                    = __h.get()->__ptr();
         }
         else
         {
             __h->__next_ = __pn->__next_;
-            __pn->__next_ = __h.get();
+            __pn->__next_ = static_cast<__next_pointer>(__h.get());
         }
-        __nd = __h.release();
+        __nd = static_cast<__next_pointer>(__h.release());
         // increment size
         ++size();
         __inserted = true;
@@ -2149,17 +2124,17 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__rehash(size_type __nbc)
     {
         for (size_type __i = 0; __i < __nbc; ++__i)
             __bucket_list_[__i] = nullptr;
-        __node_pointer __pp(static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first())));
-        __node_pointer __cp = __pp->__next_;
+        __next_pointer __pp = __p1_.first().__ptr();
+        __next_pointer __cp = __pp->__next_;
         if (__cp != nullptr)
         {
-            size_type __chash = __constrain_hash(__cp->__hash_, __nbc);
+            size_type __chash = __constrain_hash(__cp->__hash(), __nbc);
             __bucket_list_[__chash] = __pp;
             size_type __phash = __chash;
             for (__pp = __cp, __cp = __cp->__next_; __cp != nullptr;
                                                            __cp = __pp->__next_)
             {
-                __chash = __constrain_hash(__cp->__hash_, __nbc);
+                __chash = __constrain_hash(__cp->__hash(), __nbc);
                 if (__chash == __phash)
                     __pp = __cp;
                 else
@@ -2172,9 +2147,10 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::__rehash(size_type __nbc)
                     }
                     else
                     {
-                        __node_pointer __np = __cp;
+                        __next_pointer __np = __cp;
                         for (; __np->__next_ != nullptr &&
-                               key_eq()(__cp->__value_, __np->__next_->__value_);
+                               key_eq()(__cp->__upcast()->__value_,
+                                        __np->__next_->__upcast()->__value_);
                                                            __np = __np->__next_)
                             ;
                         __pp->__next_ = __np->__next_;
@@ -2198,15 +2174,16 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::find(const _Key& __k)
     if (__bc != 0)
     {
         size_t __chash = __constrain_hash(__hash, __bc);
-        __node_pointer __nd = __bucket_list_[__chash];
+        __next_pointer __nd = __bucket_list_[__chash];
         if (__nd != nullptr)
         {
             for (__nd = __nd->__next_; __nd != nullptr &&
-                (__nd->__hash_ == __hash
-                  || __constrain_hash(__nd->__hash_, __bc) == __chash);
+                (__nd->__hash() == __hash
+                  || __constrain_hash(__nd->__hash(), __bc) == __chash);
                                                            __nd = __nd->__next_)
             {
-                if ((__nd->__hash_ == __hash) && key_eq()(__nd->__value_, __k))
+                if ((__nd->__hash() == __hash)
+                    && key_eq()(__nd->__upcast()->__value_, __k))
 #if _LIBCPP_DEBUG_LEVEL >= 2
                     return iterator(__nd, this);
 #else
@@ -2228,14 +2205,16 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::find(const _Key& __k) const
     if (__bc != 0)
     {
         size_t __chash = __constrain_hash(__hash, __bc);
-        __node_const_pointer __nd = __bucket_list_[__chash];
+        __next_pointer __nd = __bucket_list_[__chash];
         if (__nd != nullptr)
         {
             for (__nd = __nd->__next_; __nd != nullptr &&
-                (__hash == __nd->__hash_ || __constrain_hash(__nd->__hash_, __bc) == __chash);
+                (__hash == __nd->__hash()
+                    || __constrain_hash(__nd->__hash(), __bc) == __chash);
                                                            __nd = __nd->__next_)
             {
-                if ((__nd->__hash_ == __hash) && key_eq()(__nd->__value_, __k))
+                if ((__nd->__hash() == __hash)
+                    && key_eq()(__nd->__upcast()->__value_, __k))
 #if _LIBCPP_DEBUG_LEVEL >= 2
                     return const_iterator(__nd, this);
 #else
@@ -2320,7 +2299,7 @@ template <class _Tp, class _Hash, class _Equal, class _Alloc>
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::erase(const_iterator __p)
 {
-    __node_pointer __np = __p.__node_;
+    __next_pointer __np = __p.__node_;
 #if _LIBCPP_DEBUG_LEVEL >= 2
     _LIBCPP_ASSERT(__get_const_db()->__find_c_from_i(&__p) == this,
         "unordered container erase(iterator) called with an iterator not"
@@ -2354,7 +2333,7 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::erase(const_iterator __first,
         ++__first;
         erase(__p);
     }
-    __node_pointer __np = __last.__node_;
+    __next_pointer __np = __last.__node_;
 #if _LIBCPP_DEBUG_LEVEL >= 2
     return iterator (__np, this);
 #else
@@ -2398,26 +2377,27 @@ typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_holder
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::remove(const_iterator __p) _NOEXCEPT
 {
     // current node
-    __node_pointer __cn = __p.__node_;
+    __next_pointer __cn = __p.__node_;
     size_type __bc = bucket_count();
-    size_t __chash = __constrain_hash(__cn->__hash_, __bc);
+    size_t __chash = __constrain_hash(__cn->__hash(), __bc);
     // find previous node
-    __node_pointer __pn = __bucket_list_[__chash];
+    __next_pointer __pn = __bucket_list_[__chash];
     for (; __pn->__next_ != __cn; __pn = __pn->__next_)
         ;
     // Fix up __bucket_list_
         // if __pn is not in same bucket (before begin is not in same bucket) &&
         //    if __cn->__next_ is not in same bucket (nullptr is not in same bucket)
-    if (__pn == static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()))
-                            || __constrain_hash(__pn->__hash_, __bc) != __chash)
+    if (__pn == __p1_.first().__ptr()
+            || __constrain_hash(__pn->__hash(), __bc) != __chash)
     {
-        if (__cn->__next_ == nullptr || __constrain_hash(__cn->__next_->__hash_, __bc) != __chash)
+        if (__cn->__next_ == nullptr
+            || __constrain_hash(__cn->__next_->__hash(), __bc) != __chash)
             __bucket_list_[__chash] = nullptr;
     }
         // if __cn->__next_ is not in same bucket (nullptr is in same bucket)
     if (__cn->__next_ != nullptr)
     {
-        size_t __nhash = __constrain_hash(__cn->__next_->__hash_, __bc);
+        size_t __nhash = __constrain_hash(__cn->__next_->__hash(), __bc);
         if (__nhash != __chash)
             __bucket_list_[__nhash] = __pn;
     }
@@ -2427,20 +2407,20 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::remove(const_iterator __p) _NOEXCEPT
     --size();
 #if _LIBCPP_DEBUG_LEVEL >= 2
     __c_node* __c = __get_db()->__find_c_and_lock(this);
-    for (__i_node** __p = __c->end_; __p != __c->beg_; )
+    for (__i_node** __dp = __c->end_; __dp != __c->beg_; )
     {
-        --__p;
-        iterator* __i = static_cast<iterator*>((*__p)->__i_);
+        --__dp;
+        iterator* __i = static_cast<iterator*>((*__dp)->__i_);
         if (__i->__node_ == __cn)
         {
-            (*__p)->__c_ = nullptr;
-            if (--__c->end_ != __p)
-                memmove(__p, __p+1, (__c->end_ - __p)*sizeof(__i_node*));
+            (*__dp)->__c_ = nullptr;
+            if (--__c->end_ != __dp)
+                memmove(__dp, __dp+1, (__c->end_ - __dp)*sizeof(__i_node*));
         }
     }
     __get_db()->unlock();
 #endif
-    return __node_holder(__cn, _Dp(__node_alloc(), true));
+    return __node_holder(__cn->__upcast(), _Dp(__node_alloc(), true));
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
@@ -2543,7 +2523,7 @@ template <class _Tp, class _Hash, class _Equal, class _Alloc>
 void
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::swap(__hash_table& __u)
 #if _LIBCPP_STD_VER <= 11
-    _NOEXCEPT_(
+    _NOEXCEPT_DEBUG_(
         __is_nothrow_swappable<hasher>::value && __is_nothrow_swappable<key_equal>::value
         && (!allocator_traits<__pointer_allocator>::propagate_on_container_swap::value
               || __is_nothrow_swappable<__pointer_allocator>::value)
@@ -2551,9 +2531,13 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::swap(__hash_table& __u)
               || __is_nothrow_swappable<__node_allocator>::value)
             )
 #else
-  _NOEXCEPT_(__is_nothrow_swappable<hasher>::value && __is_nothrow_swappable<key_equal>::value)
+  _NOEXCEPT_DEBUG_(__is_nothrow_swappable<hasher>::value && __is_nothrow_swappable<key_equal>::value)
 #endif
 {
+    _LIBCPP_ASSERT(__node_traits::propagate_on_container_swap::value ||
+                   this->__node_alloc() == __u.__node_alloc(),
+                   "list::swap: Either propagate_on_container_swap must be true"
+                   " or the allocators must compare equal");
     {
     __node_pointer_pointer __npp = __bucket_list_.release();
     __bucket_list_.reset(__u.__bucket_list_.release());
@@ -2567,11 +2551,11 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::swap(__hash_table& __u)
     __p2_.swap(__u.__p2_);
     __p3_.swap(__u.__p3_);
     if (size() > 0)
-        __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash_, bucket_count())] =
-            static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__p1_.first()));
+        __bucket_list_[__constrain_hash(__p1_.first().__next_->__hash(), bucket_count())] =
+            __p1_.first().__ptr();
     if (__u.size() > 0)
-        __u.__bucket_list_[__constrain_hash(__u.__p1_.first().__next_->__hash_, __u.bucket_count())] =
-            static_cast<__node_pointer>(pointer_traits<__node_base_pointer>::pointer_to(__u.__p1_.first()));
+        __u.__bucket_list_[__constrain_hash(__u.__p1_.first().__next_->__hash(), __u.bucket_count())] =
+            __u.__p1_.first().__ptr();
 #if _LIBCPP_DEBUG_LEVEL >= 2
     __get_db()->swap(this, &__u);
 #endif
@@ -2583,13 +2567,13 @@ __hash_table<_Tp, _Hash, _Equal, _Alloc>::bucket_size(size_type __n) const
 {
     _LIBCPP_ASSERT(__n < bucket_count(),
         "unordered container::bucket_size(n) called with n >= bucket_count()");
-    __node_const_pointer __np = __bucket_list_[__n];
+    __next_pointer __np = __bucket_list_[__n];
     size_type __bc = bucket_count();
     size_type __r = 0;
     if (__np != nullptr)
     {
         for (__np = __np->__next_; __np != nullptr &&
-                                   __constrain_hash(__np->__hash_, __bc) == __n;
+                                   __constrain_hash(__np->__hash(), __bc) == __n;
                                                     __np = __np->__next_, ++__r)
             ;
     }