libcxx: update to LLVM 18

release/18.x branch, commit 78b99c73ee4b96fe9ce0e294d4632326afb2db42

This adds the flag `-D_LIBCPP_HARDENING_MODE` which is determined based
on the Zig optimization mode.

This commit also fixes libunwind, libcxx, and libcxxabi to properly
report sub compilation errors.

1 files changed, 90 insertions, 117 deletions

diff --git a/lib/libcxx/include/__iterator/counted_iterator.h b/lib/libcxx/include/__iterator/counted_iterator.h
index 41b7e57d28..008c52fa87 100644
--- a/lib/libcxx/include/__iterator/counted_iterator.h
+++ b/lib/libcxx/include/__iterator/counted_iterator.h
@@ -41,121 +41,110 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 
 #if _LIBCPP_STD_VER >= 20
 
-template<class>
+template <class>
 struct __counted_iterator_concept {};
 
-template<class _Iter>
+template <class _Iter>
   requires requires { typename _Iter::iterator_concept; }
 struct __counted_iterator_concept<_Iter> {
   using iterator_concept = typename _Iter::iterator_concept;
 };
 
-template<class>
+template <class>
 struct __counted_iterator_category {};
 
-template<class _Iter>
+template <class _Iter>
   requires requires { typename _Iter::iterator_category; }
 struct __counted_iterator_category<_Iter> {
   using iterator_category = typename _Iter::iterator_category;
 };
 
-template<class>
+template <class>
 struct __counted_iterator_value_type {};
 
-template<indirectly_readable _Iter>
+template <indirectly_readable _Iter>
 struct __counted_iterator_value_type<_Iter> {
   using value_type = iter_value_t<_Iter>;
 };
 
-template<input_or_output_iterator _Iter>
+template <input_or_output_iterator _Iter>
 class counted_iterator
-  : public __counted_iterator_concept<_Iter>
-  , public __counted_iterator_category<_Iter>
-  , public __counted_iterator_value_type<_Iter>
-{
+    : public __counted_iterator_concept<_Iter>,
+      public __counted_iterator_category<_Iter>,
+      public __counted_iterator_value_type<_Iter> {
 public:
-  _LIBCPP_NO_UNIQUE_ADDRESS _Iter __current_ = _Iter();
-  iter_difference_t<_Iter> __count_ = 0;
-
-  using iterator_type = _Iter;
+  using iterator_type   = _Iter;
   using difference_type = iter_difference_t<_Iter>;
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr counted_iterator() requires default_initializable<_Iter> = default;
+  _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator()
+    requires default_initializable<_Iter>
+  = default;
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr counted_iterator(_Iter __iter, iter_difference_t<_Iter> __n)
-   : __current_(_VSTD::move(__iter)), __count_(__n) {
+  _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator(_Iter __iter, iter_difference_t<_Iter> __n)
+      : __current_(std::move(__iter)), __count_(__n) {
     _LIBCPP_ASSERT_UNCATEGORIZED(__n >= 0, "__n must not be negative.");
   }
 
-  template<class _I2>
+  template <class _I2>
     requires convertible_to<const _I2&, _Iter>
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr counted_iterator(const counted_iterator<_I2>& __other)
-   : __current_(__other.__current_), __count_(__other.__count_) {}
+  _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator(const counted_iterator<_I2>& __other)
+      : __current_(__other.__current_), __count_(__other.__count_) {}
 
-  template<class _I2>
+  template <class _I2>
     requires assignable_from<_Iter&, const _I2&>
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr counted_iterator& operator=(const counted_iterator<_I2>& __other) {
+  _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator& operator=(const counted_iterator<_I2>& __other) {
     __current_ = __other.__current_;
-    __count_ = __other.__count_;
+    __count_   = __other.__count_;
     return *this;
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr const _Iter& base() const& noexcept { return __current_; }
+  _LIBCPP_HIDE_FROM_ABI constexpr const _Iter& base() const& noexcept { return __current_; }
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr _Iter base() && { return _VSTD::move(__current_); }
+  _LIBCPP_HIDE_FROM_ABI constexpr _Iter base() && { return std::move(__current_); }
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr iter_difference_t<_Iter> count() const noexcept { return __count_; }
+  _LIBCPP_HIDE_FROM_ABI constexpr iter_difference_t<_Iter> count() const noexcept { return __count_; }
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr decltype(auto) operator*() {
-    _LIBCPP_ASSERT_UNCATEGORIZED(__count_ > 0, "Iterator is equal to or past end.");
+  _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator*() {
+    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count_ > 0, "Iterator is equal to or past end.");
     return *__current_;
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr decltype(auto) operator*() const
+  _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator*() const
     requires __dereferenceable<const _Iter>
   {
-    _LIBCPP_ASSERT_UNCATEGORIZED(__count_ > 0, "Iterator is equal to or past end.");
+    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__count_ > 0, "Iterator is equal to or past end.");
     return *__current_;
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr auto operator->() const noexcept
+  _LIBCPP_HIDE_FROM_ABI constexpr auto operator->() const noexcept
     requires contiguous_iterator<_Iter>
   {
-    return _VSTD::to_address(__current_);
+    return std::to_address(__current_);
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr counted_iterator& operator++() {
+  _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator& operator++() {
     _LIBCPP_ASSERT_UNCATEGORIZED(__count_ > 0, "Iterator already at or past end.");
     ++__current_;
     --__count_;
     return *this;
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  decltype(auto) operator++(int) {
+  _LIBCPP_HIDE_FROM_ABI decltype(auto) operator++(int) {
     _LIBCPP_ASSERT_UNCATEGORIZED(__count_ > 0, "Iterator already at or past end.");
     --__count_;
-#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
-    try { return __current_++; }
-    catch(...) { ++__count_; throw; }
-#else
+#  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+    try {
+      return __current_++;
+    } catch (...) {
+      ++__count_;
+      throw;
+    }
+#  else
     return __current_++;
-#endif // _LIBCPP_HAS_NO_EXCEPTIONS
+#  endif // _LIBCPP_HAS_NO_EXCEPTIONS
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr counted_iterator operator++(int)
+  _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator operator++(int)
     requires forward_iterator<_Iter>
   {
     _LIBCPP_ASSERT_UNCATEGORIZED(__count_ > 0, "Iterator already at or past end.");
@@ -164,8 +153,7 @@ public:
     return __tmp;
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr counted_iterator& operator--()
+  _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator& operator--()
     requires bidirectional_iterator<_Iter>
   {
     --__current_;
@@ -173,8 +161,7 @@ public:
     return *this;
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr counted_iterator operator--(int)
+  _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator operator--(int)
     requires bidirectional_iterator<_Iter>
   {
     counted_iterator __tmp = *this;
@@ -182,23 +169,20 @@ public:
     return __tmp;
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr counted_iterator operator+(iter_difference_t<_Iter> __n) const
+  _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator operator+(iter_difference_t<_Iter> __n) const
     requires random_access_iterator<_Iter>
   {
     return counted_iterator(__current_ + __n, __count_ - __n);
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  friend constexpr counted_iterator operator+(
-    iter_difference_t<_Iter> __n, const counted_iterator& __x)
+  _LIBCPP_HIDE_FROM_ABI friend constexpr counted_iterator
+  operator+(iter_difference_t<_Iter> __n, const counted_iterator& __x)
     requires random_access_iterator<_Iter>
   {
     return __x + __n;
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr counted_iterator& operator+=(iter_difference_t<_Iter> __n)
+  _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator& operator+=(iter_difference_t<_Iter> __n)
     requires random_access_iterator<_Iter>
   {
     _LIBCPP_ASSERT_UNCATEGORIZED(__n <= __count_, "Cannot advance iterator past end.");
@@ -207,104 +191,93 @@ public:
     return *this;
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr counted_iterator operator-(iter_difference_t<_Iter> __n) const
+  _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator operator-(iter_difference_t<_Iter> __n) const
     requires random_access_iterator<_Iter>
   {
     return counted_iterator(__current_ - __n, __count_ + __n);
   }
 
-  template<common_with<_Iter> _I2>
-  _LIBCPP_HIDE_FROM_ABI
-  friend constexpr iter_difference_t<_I2> operator-(
-    const counted_iterator& __lhs, const counted_iterator<_I2>& __rhs)
-  {
+  template <common_with<_Iter> _I2>
+  _LIBCPP_HIDE_FROM_ABI friend constexpr iter_difference_t<_I2>
+  operator-(const counted_iterator& __lhs, const counted_iterator<_I2>& __rhs) {
     return __rhs.__count_ - __lhs.__count_;
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  friend constexpr iter_difference_t<_Iter> operator-(
-    const counted_iterator& __lhs, default_sentinel_t)
-  {
+  _LIBCPP_HIDE_FROM_ABI friend constexpr iter_difference_t<_Iter>
+  operator-(const counted_iterator& __lhs, default_sentinel_t) {
     return -__lhs.__count_;
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  friend constexpr iter_difference_t<_Iter> operator-(
-    default_sentinel_t, const counted_iterator& __rhs)
-  {
+  _LIBCPP_HIDE_FROM_ABI friend constexpr iter_difference_t<_Iter>
+  operator-(default_sentinel_t, const counted_iterator& __rhs) {
     return __rhs.__count_;
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr counted_iterator& operator-=(iter_difference_t<_Iter> __n)
+  _LIBCPP_HIDE_FROM_ABI constexpr counted_iterator& operator-=(iter_difference_t<_Iter> __n)
     requires random_access_iterator<_Iter>
   {
-    _LIBCPP_ASSERT_UNCATEGORIZED(-__n <= __count_,
-                                 "Attempt to subtract too large of a size: "
-                                 "counted_iterator would be decremented before the "
-                                 "first element of its range.");
+    _LIBCPP_ASSERT_UNCATEGORIZED(
+        -__n <= __count_,
+        "Attempt to subtract too large of a size: "
+        "counted_iterator would be decremented before the "
+        "first element of its range.");
     __current_ -= __n;
     __count_ += __n;
     return *this;
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  constexpr decltype(auto) operator[](iter_difference_t<_Iter> __n) const
+  _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator[](iter_difference_t<_Iter> __n) const
     requires random_access_iterator<_Iter>
   {
-    _LIBCPP_ASSERT_UNCATEGORIZED(__n < __count_, "Subscript argument must be less than size.");
+    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__n < __count_, "Subscript argument must be less than size.");
     return __current_[__n];
   }
 
-  template<common_with<_Iter> _I2>
-  _LIBCPP_HIDE_FROM_ABI
-  friend constexpr bool operator==(
-    const counted_iterator& __lhs, const counted_iterator<_I2>& __rhs)
-  {
+  template <common_with<_Iter> _I2>
+  _LIBCPP_HIDE_FROM_ABI friend constexpr bool
+  operator==(const counted_iterator& __lhs, const counted_iterator<_I2>& __rhs) {
     return __lhs.__count_ == __rhs.__count_;
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  friend constexpr bool operator==(
-    const counted_iterator& __lhs, default_sentinel_t)
-  {
+  _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const counted_iterator& __lhs, default_sentinel_t) {
     return __lhs.__count_ == 0;
   }
 
-  template<common_with<_Iter> _I2>
-  _LIBCPP_HIDE_FROM_ABI friend constexpr strong_ordering operator<=>(
-    const counted_iterator& __lhs, const counted_iterator<_I2>& __rhs)
-  {
+  template <common_with<_Iter> _I2>
+  _LIBCPP_HIDE_FROM_ABI friend constexpr strong_ordering
+  operator<=>(const counted_iterator& __lhs, const counted_iterator<_I2>& __rhs) {
     return __rhs.__count_ <=> __lhs.__count_;
   }
 
-  _LIBCPP_HIDE_FROM_ABI
-  friend constexpr iter_rvalue_reference_t<_Iter> iter_move(const counted_iterator& __i)
-    noexcept(noexcept(ranges::iter_move(__i.__current_)))
-      requires input_iterator<_Iter>
+  _LIBCPP_HIDE_FROM_ABI friend constexpr iter_rvalue_reference_t<_Iter>
+  iter_move(const counted_iterator& __i) noexcept(noexcept(ranges::iter_move(__i.__current_)))
+    requires input_iterator<_Iter>
   {
-    _LIBCPP_ASSERT_UNCATEGORIZED(__i.__count_ > 0, "Iterator must not be past end of range.");
+    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(__i.__count_ > 0, "Iterator must not be past end of range.");
     return ranges::iter_move(__i.__current_);
   }
 
-  template<indirectly_swappable<_Iter> _I2>
-  _LIBCPP_HIDE_FROM_ABI
-  friend constexpr void iter_swap(const counted_iterator& __x, const counted_iterator<_I2>& __y)
-    noexcept(noexcept(ranges::iter_swap(__x.__current_, __y.__current_)))
-  {
-    _LIBCPP_ASSERT_UNCATEGORIZED(__x.__count_ > 0 && __y.__count_ > 0,
-                                 "Iterators must not be past end of range.");
+  template <indirectly_swappable<_Iter> _I2>
+  _LIBCPP_HIDE_FROM_ABI friend constexpr void
+  iter_swap(const counted_iterator& __x,
+            const counted_iterator<_I2>& __y) noexcept(noexcept(ranges::iter_swap(__x.__current_, __y.__current_))) {
+    _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(
+        __x.__count_ > 0 && __y.__count_ > 0, "Iterators must not be past end of range.");
     return ranges::iter_swap(__x.__current_, __y.__current_);
   }
+
+private:
+  _LIBCPP_NO_UNIQUE_ADDRESS _Iter __current_ = _Iter();
+  iter_difference_t<_Iter> __count_          = 0;
+  template <input_or_output_iterator _OtherIter>
+  friend class counted_iterator;
 };
 _LIBCPP_CTAD_SUPPORTED_FOR_TYPE(counted_iterator);
 
-template<input_iterator _Iter>
+template <input_iterator _Iter>
   requires same_as<_ITER_TRAITS<_Iter>, iterator_traits<_Iter>>
 struct iterator_traits<counted_iterator<_Iter>> : iterator_traits<_Iter> {
-  using pointer = conditional_t<contiguous_iterator<_Iter>,
-                                add_pointer_t<iter_reference_t<_Iter>>, void>;
+  using pointer = conditional_t<contiguous_iterator<_Iter>, add_pointer_t<iter_reference_t<_Iter>>, void>;
 };
 
 #endif // _LIBCPP_STD_VER >= 20