Add libc++ and libc++abi to third-party.

third_party/libcxx/include/optional

+// -*- C++ -*-
+//===-------------------------- optional ----------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_OPTIONAL
+#define _LIBCPP_OPTIONAL
+
+/*
+    optional synopsis
+
+// C++1y
+
+#include <initializer_list>
+
+namespace std
+{
+
+// optional for object types
+template <class T>
+class optional
+{
+public:
+    typedef T value_type;
+
+    // constructors
+    constexpr optional() noexcept;
+    constexpr optional(nullopt_t) noexcept;
+    optional(const optional&);
+    optional(optional&&) noexcept(is_nothrow_move_constructible<T>::value);
+    constexpr optional(const T&);
+    constexpr optional(T&&);
+    template <class... Args> constexpr explicit optional(in_place_t, Args&&...);
+    template <class U, class... Args>
+        constexpr explicit optional(in_place_t, initializer_list<U>, Args&&...);
+
+    // destructor
+    ~optional();
+
+    // assignment
+    optional& operator=(nullopt_t) noexcept;
+    optional& operator=(const optional&);
+    optional& operator=(optional&&)
+        noexcept(is_nothrow_move_assignable<T>::value &&
+                 is_nothrow_move_constructible<T>::value);
+    template <class U> optional& operator=(U&&);
+    template <class... Args> void emplace(Args&&...);
+    template <class U, class... Args> void emplace(initializer_list<U>, Args&&...);
+
+    // swap
+    void swap(optional&)
+        noexcept(is_nothrow_move_constructible<T>::value &&
+                 noexcept(swap(declval<T&>(), declval<T&>())));
+
+    // observers
+    constexpr T const* operator->() const;
+    T* operator->();
+    constexpr T const& operator*() const;
+    T& operator*();
+    constexpr explicit operator bool() const noexcept;
+    constexpr T const& value() const;
+    T& value();
+    template <class U> constexpr T value_or(U&&) const&;
+    template <class U> T value_or(U&&) &&;
+};
+
+// In-place construction
+struct in_place_t{};
+constexpr in_place_t in_place{};
+
+// Disengaged state indicator
+struct nullopt_t{see below};
+constexpr nullopt_t nullopt(unspecified);
+
+// class bad_optional_access
+class bad_optional_access
+    : public logic_error
+{
+public:
+    explicit bad_optional_access(const string& what_arg);
+    explicit bad_optional_access(const char* what_arg);
+};
+
+// Relational operators
+template <class T> constexpr bool operator==(const optional<T>&, const optional<T>&);
+template <class T> constexpr bool operator< (const optional<T>&, const optional<T>&);
+
+// Comparison with nullopt
+template <class T> constexpr bool operator==(const optional<T>&, nullopt_t) noexcept;
+template <class T> constexpr bool operator==(nullopt_t, const optional<T>&) noexcept;
+template <class T> constexpr bool operator<(const optional<T>&, nullopt_t) noexcept;
+template <class T> constexpr bool operator<(nullopt_t, const optional<T>&) noexcept;
+
+// Comparison with T
+template <class T> constexpr bool operator==(const optional<T>&, const T&);
+template <class T> constexpr bool operator==(const T&, const optional<T>&);
+template <class T> constexpr bool operator<(const optional<T>&, const T&);
+template <class T> constexpr bool operator<(const T&, const optional<T>&);
+
+// Specialized algorithms
+template <class T> void swap(optional<T>&, optional<T>&) noexcept(see below);
+template <class T> constexpr optional<typename decay<T>::type> make_optional(T&&);
+
+// hash support
+template <class T> struct hash;
+template <class T> struct hash<optional<T>>;
+
+}  // std
+
+*/
+
+#include <__config>
+#include <functional>
+#include <stdexcept>
+
+namespace std  // purposefully not using versioning namespace
+{
+
+class _LIBCPP_EXCEPTION_ABI bad_optional_access
+    : public logic_error
+{
+public:
+#if _LIBCPP_STD_VER > 11
+    _LIBCPP_INLINE_VISIBILITY explicit bad_optional_access(const string& __arg)
+        : logic_error(__arg) {}
+    _LIBCPP_INLINE_VISIBILITY explicit bad_optional_access(const char* __arg)
+        : logic_error(__arg) {}
+    _LIBCPP_INLINE_VISIBILITY bad_optional_access(const bad_optional_access&) noexcept = default;
+    _LIBCPP_INLINE_VISIBILITY bad_optional_access& operator=(const bad_optional_access&) noexcept = default;
+#else
+private:
+    bad_optional_access(const bad_optional_access&);
+    bad_optional_access& operator=(const bad_optional_access&);
+public:
+#endif  // _LIBCPP_STD_VER > 11
+    // Get the key function ~bad_optional_access() into the dylib even if not compiling for C++1y
+    virtual ~bad_optional_access() _NOEXCEPT;
+};
+
+}  // std
+
+#if _LIBCPP_STD_VER > 11
+
+#include <initializer_list>
+#include <type_traits>
+#include <new>
+#include <__functional_base>
+
+#include <__undef_min_max>
+
+#ifdef _LIBCPP_DEBUG
+#   include <__debug>
+#else
+#   define _LIBCPP_ASSERT(x, m) ((void)0)
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct in_place_t {};
+constexpr in_place_t in_place{};
+
+struct nullopt_t
+{
+    explicit constexpr nullopt_t(int) noexcept {}
+};
+
+constexpr nullopt_t nullopt{0};
+
+template <class _Tp, bool = is_trivially_destructible<_Tp>::value>
+class __optional_storage
+{
+protected:
+    typedef _Tp value_type;
+    union
+    {
+        char __null_state_;
+        value_type __val_;
+    };
+    bool __engaged_ = false;
+
+    _LIBCPP_INLINE_VISIBILITY
+    ~__optional_storage()
+    {
+        if (__engaged_)
+            __val_.~value_type();
+    }
+
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr __optional_storage() noexcept
+        :  __null_state_('\0') {}
+
+    _LIBCPP_INLINE_VISIBILITY
+    __optional_storage(const __optional_storage& __x)
+        :  __engaged_(__x.__engaged_)
+        {
+            if (__engaged_)
+                ::new(_VSTD::addressof(__val_)) value_type(__x.__val_);
+        }
+
+    _LIBCPP_INLINE_VISIBILITY
+    __optional_storage(__optional_storage&& __x)
+                      noexcept(is_nothrow_move_constructible<value_type>::value)
+        :  __engaged_(__x.__engaged_)
+        {
+            if (__engaged_)
+                ::new(_VSTD::addressof(__val_)) value_type(_VSTD::move(__x.__val_));
+        }
+
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr __optional_storage(const value_type& __v)
+        :  __val_(__v),
+           __engaged_(true) {}
+
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr __optional_storage(value_type&& __v)
+        :  __val_(_VSTD::move(__v)),
+           __engaged_(true) {}
+
+    template <class... _Args>
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr
+    explicit __optional_storage(in_place_t, _Args&&... __args)
+       :  __val_(_VSTD::forward<_Args>(__args)...),
+           __engaged_(true) {}
+};
+
+template <class _Tp>
+class __optional_storage<_Tp, true>
+{
+protected:
+    typedef _Tp value_type;
+    union
+    {
+        char __null_state_;
+        value_type __val_;
+    };
+    bool __engaged_ = false;
+
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr __optional_storage() noexcept
+        :  __null_state_('\0') {}
+
+    _LIBCPP_INLINE_VISIBILITY
+    __optional_storage(const __optional_storage& __x)
+        :  __engaged_(__x.__engaged_)
+        {
+            if (__engaged_)
+                ::new(_VSTD::addressof(__val_)) value_type(__x.__val_);
+        }
+
+    _LIBCPP_INLINE_VISIBILITY
+    __optional_storage(__optional_storage&& __x)
+                      noexcept(is_nothrow_move_constructible<value_type>::value)
+        :  __engaged_(__x.__engaged_)
+        {
+            if (__engaged_)
+                ::new(_VSTD::addressof(__val_)) value_type(_VSTD::move(__x.__val_));
+        }
+
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr __optional_storage(const value_type& __v)
+        :  __val_(__v),
+           __engaged_(true) {}
+
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr __optional_storage(value_type&& __v)
+        :  __val_(_VSTD::move(__v)),
+           __engaged_(true) {}
+
+    template <class... _Args>
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr
+    explicit __optional_storage(in_place_t, _Args&&... __args)
+       :  __val_(_VSTD::forward<_Args>(__args)...),
+           __engaged_(true) {}
+};
+
+template <class _Tp>
+class optional
+    : private __optional_storage<_Tp>
+{
+    typedef __optional_storage<_Tp> __base;
+public:
+    typedef _Tp value_type;
+
+    static_assert(!is_reference<value_type>::value,
+              "Instantiation of optional with a reference type is ill-formed.");
+    static_assert(!is_same<typename remove_cv<value_type>::type, in_place_t>::value,
+              "Instantiation of optional with a in_place_t type is ill-formed.");
+    static_assert(!is_same<typename remove_cv<value_type>::type, nullopt_t>::value,
+              "Instantiation of optional with a nullopt_t type is ill-formed.");
+    static_assert(is_object<value_type>::value,
+        "Instantiation of optional with a non-object type is undefined behavior.");
+    static_assert(is_nothrow_destructible<value_type>::value,
+        "Instantiation of optional with an object type that is not noexcept destructible is undefined behavior.");
+
+    _LIBCPP_INLINE_VISIBILITY constexpr optional() noexcept {}
+    _LIBCPP_INLINE_VISIBILITY optional(const optional&) = default;
+    _LIBCPP_INLINE_VISIBILITY optional(optional&&) = default;
+    _LIBCPP_INLINE_VISIBILITY ~optional() = default;
+    _LIBCPP_INLINE_VISIBILITY constexpr optional(nullopt_t) noexcept {}
+    _LIBCPP_INLINE_VISIBILITY constexpr optional(const value_type& __v)
+        : __base(__v) {}
+    _LIBCPP_INLINE_VISIBILITY constexpr optional(value_type&& __v)
+        : __base(_VSTD::move(__v)) {}
+
+    template <class... _Args,
+              class = typename enable_if
+                      <
+                           is_constructible<value_type, _Args...>::value
+                      >::type
+             >
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr
+    explicit optional(in_place_t, _Args&&... __args)
+        : __base(in_place, _VSTD::forward<_Args>(__args)...) {}
+
+    template <class _Up, class... _Args,
+              class = typename enable_if
+                      <
+                           is_constructible<value_type, initializer_list<_Up>&, _Args...>::value
+                      >::type
+             >
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr
+    explicit optional(in_place_t, initializer_list<_Up> __il, _Args&&... __args)
+        : __base(in_place, __il, _VSTD::forward<_Args>(__args)...) {}
+
+    _LIBCPP_INLINE_VISIBILITY
+    optional& operator=(nullopt_t) noexcept
+    {
+        if (this->__engaged_)
+        {
+            this->__val_.~value_type();
+            this->__engaged_ = false;
+        }
+        return *this;
+    }
+
+    _LIBCPP_INLINE_VISIBILITY
+    optional&
+    operator=(const optional& __opt)
+    {
+        if (this->__engaged_ == __opt.__engaged_)
+        {
+            if (this->__engaged_)
+                this->__val_ = __opt.__val_;
+        }
+        else
+        {
+            if (this->__engaged_)
+                this->__val_.~value_type();
+            else
+                ::new(_VSTD::addressof(this->__val_)) value_type(__opt.__val_);
+            this->__engaged_ = __opt.__engaged_;
+        }
+        return *this;
+    }
+
+    _LIBCPP_INLINE_VISIBILITY
+    optional&
+    operator=(optional&& __opt)
+        noexcept(is_nothrow_move_assignable<value_type>::value &&
+                 is_nothrow_move_constructible<value_type>::value)
+    {
+        if (this->__engaged_ == __opt.__engaged_)
+        {
+            if (this->__engaged_)
+                this->__val_ = _VSTD::move(__opt.__val_);
+        }
+        else
+        {
+            if (this->__engaged_)
+                this->__val_.~value_type();
+            else
+                ::new(_VSTD::addressof(this->__val_)) value_type(_VSTD::move(__opt.__val_));
+            this->__engaged_ = __opt.__engaged_;
+        }
+        return *this;
+    }
+
+    template <class _Up,
+              class = typename enable_if
+                      <
+                          is_same<typename remove_reference<_Up>::type, value_type>::value &&
+                          is_constructible<value_type, _Up>::value &&
+                          is_assignable<value_type&, _Up>::value
+                      >::type
+             >
+    _LIBCPP_INLINE_VISIBILITY
+    optional&
+    operator=(_Up&& __v)
+    {
+        if (this->__engaged_)
+            this->__val_ = _VSTD::forward<_Up>(__v);
+        else
+        {
+            ::new(_VSTD::addressof(this->__val_)) value_type(_VSTD::forward<_Up>(__v));
+            this->__engaged_ = true;
+        }
+        return *this;
+    }
+
+    template <class... _Args,
+              class = typename enable_if
+                      <
+                          is_constructible<value_type, _Args...>::value
+                      >::type
+             >
+    _LIBCPP_INLINE_VISIBILITY
+    void
+    emplace(_Args&&... __args)
+    {
+        *this = nullopt;
+        ::new(_VSTD::addressof(this->__val_)) value_type(_VSTD::forward<_Args>(__args)...);
+        this->__engaged_ = true;
+    }
+
+    template <class _Up, class... _Args,
+              class = typename enable_if
+                      <
+                          is_constructible<value_type, initializer_list<_Up>&, _Args...>::value
+                      >::type
+             >
+    _LIBCPP_INLINE_VISIBILITY
+    void
+    emplace(initializer_list<_Up> __il, _Args&&... __args)
+    {
+        *this = nullopt;
+        ::new(_VSTD::addressof(this->__val_)) value_type(__il, _VSTD::forward<_Args>(__args)...);
+        this->__engaged_ = true;
+    }
+
+    _LIBCPP_INLINE_VISIBILITY
+    void
+    swap(optional& __opt)
+        noexcept(is_nothrow_move_constructible<value_type>::value &&
+                 __is_nothrow_swappable<value_type>::value)
+    {
+        using _VSTD::swap;
+        if (this->__engaged_ == __opt.__engaged_)
+        {
+            if (this->__engaged_)
+                swap(this->__val_, __opt.__val_);
+        }
+        else
+        {
+            if (this->__engaged_)
+            {
+                ::new(_VSTD::addressof(__opt.__val_)) value_type(_VSTD::move(this->__val_));
+                this->__val_.~value_type();
+            }
+            else
+            {
+                ::new(_VSTD::addressof(this->__val_)) value_type(_VSTD::move(__opt.__val_));
+                __opt.__val_.~value_type();
+            }
+            swap(this->__engaged_, __opt.__engaged_);
+        }
+    }
+
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr
+    value_type const*
+    operator->() const
+    {
+        _LIBCPP_ASSERT(this->__engaged_, "optional operator-> called for disengaged value");
+        return __operator_arrow(__has_operator_addressof<value_type>{});
+    }
+
+    _LIBCPP_INLINE_VISIBILITY
+    value_type*
+    operator->()
+    {
+        _LIBCPP_ASSERT(this->__engaged_, "optional operator-> called for disengaged value");
+        return _VSTD::addressof(this->__val_);
+    }
+
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr
+    const value_type&
+    operator*() const
+    {
+        _LIBCPP_ASSERT(this->__engaged_, "optional operator* called for disengaged value");
+        return this->__val_;
+    }
+
+    _LIBCPP_INLINE_VISIBILITY
+    value_type&
+    operator*()
+    {
+        _LIBCPP_ASSERT(this->__engaged_, "optional operator* called for disengaged value");
+        return this->__val_;
+    }
+
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr explicit operator bool() const noexcept {return this->__engaged_;}
+
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr value_type const& value() const
+    {
+        if (!this->__engaged_)
+            throw bad_optional_access("optional<T>::value: not engaged");
+        return this->__val_;
+    }
+
+    _LIBCPP_INLINE_VISIBILITY
+    value_type& value()
+    {
+        if (!this->__engaged_)
+            throw bad_optional_access("optional<T>::value: not engaged");
+        return this->__val_;
+    }
+
+    template <class _Up>
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr value_type value_or(_Up&& __v) const&
+    {
+        static_assert(is_copy_constructible<value_type>::value,
+                      "optional<T>::value_or: T must be copy constructible");
+        static_assert(is_convertible<_Up, value_type>::value,
+                      "optional<T>::value_or: U must be convertible to T");
+        return this->__engaged_ ? this->__val_ :
+                                  static_cast<value_type>(_VSTD::forward<_Up>(__v));
+    }
+
+    template <class _Up>
+    _LIBCPP_INLINE_VISIBILITY
+    value_type value_or(_Up&& __v) &&
+    {
+        static_assert(is_move_constructible<value_type>::value,
+                      "optional<T>::value_or: T must be move constructible");
+        static_assert(is_convertible<_Up, value_type>::value,
+                      "optional<T>::value_or: U must be convertible to T");
+        return this->__engaged_ ? _VSTD::move(this->__val_) :
+                                  static_cast<value_type>(_VSTD::forward<_Up>(__v));
+    }
+
+private:
+    _LIBCPP_INLINE_VISIBILITY
+    value_type const*
+    __operator_arrow(true_type) const
+    {
+        return _VSTD::addressof(this->__val_);
+    }
+
+    _LIBCPP_INLINE_VISIBILITY
+    constexpr
+    value_type const*
+    __operator_arrow(false_type) const
+    {
+        return &this->__val_;
+    }
+};
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+constexpr
+bool
+operator==(const optional<_Tp>& __x, const optional<_Tp>& __y)
+{
+    if (static_cast<bool>(__x) != static_cast<bool>(__y))
+        return false;
+    if (!static_cast<bool>(__x))
+        return true;
+    return *__x == *__y;
+}
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+constexpr
+bool
+operator<(const optional<_Tp>& __x, const optional<_Tp>& __y)
+{
+    if (!static_cast<bool>(__y))
+        return false;
+    if (!static_cast<bool>(__x))
+        return true;
+    return less<_Tp>{}(*__x, *__y);
+}
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+constexpr
+bool
+operator==(const optional<_Tp>& __x, nullopt_t) noexcept
+{
+    return !static_cast<bool>(__x);
+}
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+constexpr
+bool
+operator==(nullopt_t, const optional<_Tp>& __x) noexcept
+{
+    return !static_cast<bool>(__x);
+}
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+constexpr
+bool
+operator<(const optional<_Tp>&, nullopt_t) noexcept
+{
+    return false;
+}
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+constexpr
+bool
+operator<(nullopt_t, const optional<_Tp>& __x) noexcept
+{
+    return static_cast<bool>(__x);
+}
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+constexpr
+bool
+operator==(const optional<_Tp>& __x, const _Tp& __v)
+{
+    return static_cast<bool>(__x) ? *__x == __v : false;
+}
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+constexpr
+bool
+operator==(const _Tp& __v, const optional<_Tp>& __x)
+{
+    return static_cast<bool>(__x) ? *__x == __v : false;
+}
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+constexpr
+bool
+operator<(const optional<_Tp>& __x, const _Tp& __v)
+{
+    return static_cast<bool>(__x) ? less<_Tp>{}(*__x, __v) : true;
+}
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+constexpr
+bool
+operator<(const _Tp& __v, const optional<_Tp>& __x)
+{
+    return static_cast<bool>(__x) ? less<_Tp>{}(__v, *__x) : false;
+}
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+void
+swap(optional<_Tp>& __x, optional<_Tp>& __y) noexcept(noexcept(__x.swap(__y)))
+{
+    __x.swap(__y);
+}
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+constexpr
+optional<typename decay<_Tp>::type>
+make_optional(_Tp&& __v)
+{
+    return optional<typename decay<_Tp>::type>(_VSTD::forward<_Tp>(__v));
+}
+
+template <class _Tp>
+struct _LIBCPP_TYPE_VIS_ONLY hash<optional<_Tp> >
+{
+    typedef optional<_Tp> argument_type;
+    typedef size_t        result_type;
+
+    _LIBCPP_INLINE_VISIBILITY
+    result_type operator()(const argument_type& __opt) const _NOEXCEPT
+    {
+        return static_cast<bool>(__opt) ? hash<_Tp>()(*__opt) : 0;
+    }
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif  // _LIBCPP_STD_VER > 11
+
+#endif  // _LIBCPP_ARRAY