std::pmr::unsynchronized_pool_resource::do_allocate

 

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未初始化内存算法 uninitialized_copy uninitialized_fill uninitialized_move (C++17) uninitialized_default_construct (C++17) uninitialized_value_construct (C++17) destroy (C++17) destroy_at (C++17) voidify (C++20) uninitialized_copy_n (C++11) uninitialized_fill_n uninitialized_move_n (C++17) uninitialized_default_construct_n (C++17) uninitialized_value_construct_n (C++17) destroy_n (C++17) construct_at (C++20) 受约束的未初始化内存算法 ranges::uninitialized_copy (C++20) ranges::uninitialized_fill (C++20) ranges::uninitialized_move (C++20) ranges::construct_at (C++20) ranges::destroy (C++20) ranges::destroy_n (C++20) ranges::destroy_at (C++20) ranges::uninitialized_copy_n (C++20) ranges::uninitialized_fill_n (C++20) ranges::uninitialized_move_n (C++20) ranges::uninitialized_default_construct (C++20) ranges::uninitialized_value_construct (C++20) ranges::uninitialized_default_construct_n (C++20)   ranges::uninitialized_value_construct_n (C++20) 分配器 allocator allocator_traits (C++11) allocation_result (C++23) allocator_arg (C++11) uses_allocator (C++11) uses_allocator_construction_args (C++20) make_obj_using_allocator (C++20) uninitialized_construct_using_allocator (C++20) scoped_allocator_adaptor (C++11) pmr::polymorphic_allocator (C++17) 内存资源 pmr::memory_resource (C++17) pmr::get_default_resource (C++17) pmr::set_default_resource (C++17) pmr::new_delete_resource (C++17) pmr::null_memory_resource (C++17) pmr::synchronized_pool_resource (C++17) pmr::unsynchronized_pool_resource (C++17)   pmr::monotonic_buffer_resource (C++17) pmr::pool_options (C++17) 垃圾收集支持 declare_reachable (C++11)(C++23 前) undeclare_reachable (C++11)(C++23 前) declare_no_pointers (C++11)(C++23 前) undeclare_no_pointers (C++11)(C++23 前) pointer_safety (C++11)(C++23 前) get_pointer_safety (C++11)(C++23 前) 未初始化存储 raw_storage_iterator (C++20 前*) get_temporary_buffer (C++20 前*) return_temporary_buffer (C++20 前*) 显式生存期管理 start_lifetime_asstart_lifetime_as_array (C++23)(C++23)

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std::pmr::unsynchronized_pool_resource

unsynchronized_pool_resource::unsynchronized_pool_resource

unsynchronized_pool_resource::~unsynchronized_pool_resource

公开成员函数

unsynchronized_pool_resource::release

unsynchronized_pool_resource::upstream_resource

unsynchronized_pool_resource::options

受保护成员函数

unsynchronized_pool_resource::do_allocate

unsynchronized_pool_resource::do_deallocate

unsynchronized_pool_resource::do_is_equal

 

virtual void* do_allocate(std::size_t bytes, std::size_t alignment);		(C++17 起)

分配存储。

若为 bytes 大小的块所选的池不足以满足来自其内部数据结构的请求，则调用上游 memory_resources 上的 allocate() 以获得内存。

若请求的大小大于最大的池所能处理者，则通过调用上游 memory_resources 上的 allocate() 分配内存。

返回值

指向至少有 bytes 字节大小，若支持这种对齐则对齐到指定的 alignment ，否则对齐到 alignof(std::max_align_t) 的被分配存储。

异常

除非上游内存资源上的 allocate() 调用抛出异常，否则不抛出。

参阅

allocate	分配内存 (std::pmr::memory_resource 的公开成员函数)
do_allocate [虚]	分配内存 (std::pmr::memory_resource 的虚私有成员函数)