std::pmr::polymorphic_allocator<T>::deallocate_bytes

 

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std::pmr::polymorphic_allocator

成员函数

polymorphic_allocator::polymorphic_allocator

polymorphic_allocator::allocate

polymorphic_allocator::deallocate

polymorphic_allocator::construct

polymorphic_allocator::destroy (C++20/26*)

polymorphic_allocator::allocate_bytes (C++20)

polymorphic_allocator::deallocate_bytes (C++20)

polymorphic_allocator::allocate_object (C++20)

polymorphic_allocator::deallocate_object (C++20)

polymorphic_allocator::new_object (C++20)

polymorphic_allocator::delete_object (C++20)

polymorphic_allocator::select_on_container_copy_construction

polymorphic_allocator::resource

非成员函数

operator==operator!= (直到 C++20)

 

void deallocate_bytes( void* p,                        std::size_t nbytes,                        std::size_t alignment = alignof(std::max_align_t) );		(since C++20)

释放 p 指向的存储，它必须是从与 *resource() 相等的 std::pmr::memory_resource x 分配的，通常通过调用 x.allocate(nbytes, alignment)，典型地是通过调用 allocate_bytes(nbytes, alignment) 来实现。

等价于 resource()->deallocate(p, nbytes, alignment);。

参数

p	-	要释放的内存指针
nbytes	-	最初分配的字节数
alignment	-	最初分配的对齐方式

异常

不抛出异常。

注解

此函数是为了配合完全特化的分配器 std::pmr::polymorphic_allocator<> 而引入的，但它在任何特化中都可能有用。

参见

deallocate_object (C++20)	释放由 allocate_object 获得的原始内存 (公共成员函数)
delete_object (C++20)	销毁并释放对象 (公共成员函数)
deallocate [静态]	使用分配器释放存储 (std::allocator_traits<Alloc> 的公共静态成员函数)
deallocate	释放内存 (std::pmr::memory_resource 的公共成员函数)