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标准库头文件 <new>

来自 cppreference.cn
< cpp‎ | header
 
 
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<algorithm>
<numeric>
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此头文件是 动态内存管理 库的一部分,特别是提供了 底层内存管理 功能。

目录

当内存分配失败时抛出的异常
(类) [编辑]
当分配具有无效长度的数组时抛出的异常
(类) [编辑]
用于将对齐传递给感知对齐的分配和释放函数的类型
(枚举) [编辑]

类型

new 处理函数的函数指针类型
(typedef) [编辑]

标签

用于选择非抛出分配函数的标签
(标签)[编辑]
用于在 operator delete 的销毁删除重载中进行选择的标签
(标签)[编辑]

常量

避免伪共享的最小偏移量
促进真共享的最大偏移量
(常量) [编辑]

函数

分配函数
(函数) [编辑]
释放函数
(函数) [编辑]
获取当前的 new 处理函数
(函数) [编辑]
注册一个新的 new 处理函数
(函数) [编辑]
(C++17)
指针优化屏障
(函数模板) [编辑]

[编辑] 概要

namespace std {
  // storage allocation errors
  class bad_alloc;
  class bad_array_new_length;
 
  struct destroying_delete_t {
    explicit destroying_delete_t() = default;
  };
  inline constexpr destroying_delete_t destroying_delete{};
 
  // global operator new control
  enum class align_val_t : size_t {};
 
  struct nothrow_t { explicit nothrow_t() = default; };
  extern const nothrow_t nothrow;
 
  using new_handler = void (*)();
  new_handler get_new_handler() noexcept;
  new_handler set_new_handler(new_handler new_p) noexcept;
 
  // pointer optimization barrier
  template<class T> constexpr T* launder(T* p) noexcept;
 
  // hardware interference size
  inline constexpr size_t hardware_destructive_interference_size =
    /* implementation-defined */;
  inline constexpr size_t hardware_constructive_interference_size =
    /* implementation-defined */;
}
 
// storage allocation and deallocation
void* operator new(std::size_t size);
void* operator new(std::size_t size, std::align_val_t alignment);
void* operator new(std::size_t size, const std::nothrow_t&) noexcept;
void* operator new(std::size_t size, std::align_val_t alignment,
                                 const std::nothrow_t&) noexcept;
 
void  operator delete(void* ptr) noexcept;
void  operator delete(void* ptr, std::size_t size) noexcept;
void  operator delete(void* ptr, std::align_val_t alignment) noexcept;
void  operator delete(void* ptr, std::size_t size, std::align_val_t alignment) noexcept;
void  operator delete(void* ptr, const std::nothrow_t&) noexcept;
void  operator delete(void* ptr, std::align_val_t alignment,
                      const std::nothrow_t&) noexcept;
 
void* operator new[](std::size_t size);
void* operator new[](std::size_t size, std::align_val_t alignment);
void* operator new[](std::size_t size, const std::nothrow_t&) noexcept;
void* operator new[](std::size_t size, std::align_val_t alignment,
                                   const std::nothrow_t&) noexcept;
 
void  operator delete[](void* ptr) noexcept;
void  operator delete[](void* ptr, std::size_t size) noexcept;
void  operator delete[](void* ptr, std::align_val_t alignment) noexcept;
void  operator delete[](void* ptr, std::size_t size, std::align_val_t alignment) noexcept;
void  operator delete[](void* ptr, const std::nothrow_t&) noexcept;
void  operator delete[](void* ptr, std::align_val_t alignment,
                        const std::nothrow_t&) noexcept;
 
constexpr void* operator new  (std::size_t size, void* ptr) noexcept;
constexpr void* operator new[](std::size_t size, void* ptr) noexcept;
void  operator delete  (void* ptr, void*) noexcept;
void  operator delete[](void* ptr, void*) noexcept;