Revision control
++ // Copyright (C) 2023 The Qt Company Ltd.
++ // Copyright (C) 2020 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Marc Mutz <marc.mutz@kdab.com>
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
++ // Qt-Security score:significant reason:default
++
++ #ifndef Q20MEMORY_H
++ #define Q20MEMORY_H
++
++ #include <QtCore/qtconfigmacros.h>
++
++ #include <QtCore/q17memory.h>
++
++ #include <QtCore/q20type_traits.h>
++ #include <utility>
++
++ //
++ // W A R N I N G
++ // -------------
++ //
++ // This file is not part of the Qt API. Types and functions defined in this
++ // file can reliably be replaced by their std counterparts, once available.
++ // You may use these definitions in your own code, but be aware that we
++ // will remove them once Qt depends on the C++ version that supports
++ // them in namespace std. There will be NO deprecation warning, the
++ // definitions will JUST go away.
++ //
++ // If you can't agree to these terms, don't use these definitions!
++ //
++ // We mean it.
++ //
++
++ QT_BEGIN_NAMESPACE
++
++ // like std::construct_at (but not whitelisted for constexpr)
++ namespace q20 {
++ #ifdef __cpp_lib_constexpr_dynamic_alloc
++ using std::construct_at;
++ #else
++ template <typename T,
++ typename... Args,
++ typename Enable = std::void_t<decltype(::new (std::declval<void *>()) T(std::declval<Args>()...))> >
++ T *construct_at(T *ptr, Args && ... args)
++ {
++ return ::new (const_cast<void *>(static_cast<const volatile void *>(ptr)))
++ T(std::forward<Args>(args)...);
++ }
++ #endif // __cpp_lib_constexpr_dynamic_alloc
++ } // namespace q20
++
++ // like std::make_unique_for_overwrite (excl. C++23-added constexpr)
++ namespace q20 {
++ #ifdef __cpp_lib_smart_ptr_for_overwrite
++ using std::make_unique_for_overwrite;
++ #else
++ template <typename T>
++ std::enable_if_t<!std::is_array_v<T>, std::unique_ptr<T>>
++ make_unique_for_overwrite()
++ { return std::unique_ptr<T>(new T); }
++
++ template <typename T>
++ std::enable_if_t<q20::is_unbounded_array_v<T>, std::unique_ptr<T>>
++ make_unique_for_overwrite(std::size_t n)
++ { return std::unique_ptr<T>(new std::remove_extent_t<T>[n]); }
++
++ template <typename T, typename...Args>
++ std::enable_if_t<q20::is_bounded_array_v<T>>
++ make_unique_for_overwrite(Args&&...) = delete;
++
++ #endif // __cpp_lib_smart_ptr_for_overwrite
++ } // namespace q20
++
++ namespace q20 {
++ // like std::to_address
++ #ifdef __cpp_lib_to_address
++ using std::to_address;
++ #else
++ template <typename T>
++ constexpr T *to_address(T *p) noexcept {
++ // Mandates: T is not a function type.
++ static_assert(!std::is_function_v<T>, "to_address must not be used on function types");
++ return p;
++ }
++
++ template <typename Ptr, typename std::enable_if_t<!std::is_pointer_v<Ptr>, bool> = true>
++ constexpr auto to_address(const Ptr &ptr) noexcept; // fwd declared
++
++ namespace detail {
++ template <typename Ptr, typename = void>
++ struct to_address_helper {
++ static constexpr auto get(const Ptr &ptr) noexcept
++ { return q20::to_address(ptr.operator->()); }
++ };
++ template <typename Ptr>
++ struct to_address_helper<Ptr, std::void_t<
++ decltype(std::pointer_traits<Ptr>::to_address(std::declval<const Ptr&>()))
++ >>
++ {
++ static constexpr auto get(const Ptr &ptr) noexcept
++ { return std::pointer_traits<Ptr>::to_address(ptr); }
++ };
++ } // namespace detail
++
++ template <typename Ptr, typename std::enable_if_t<!std::is_pointer_v<Ptr>, bool>>
++ constexpr auto to_address(const Ptr &ptr) noexcept
++ { return detail::to_address_helper<Ptr>::get(ptr); }
++
++ #endif // __cpp_lib_to_address
++ } // namespace q20
++
++ QT_END_NAMESPACE
++
++ #endif /* Q20MEMORY_H */