使用 Std::allocator 在特定地址分配内存

Question

可以使用 std::allocator 在特定地址分配特定大小的内存吗？

Answer 1

I am working on the OS level and I need to allocate certain buffers at certain address for embedded application.

Allocation is the process of obtaining memory from the OS. Without an OS, or if you are writing the OS, you don't need to allocate the memory at all, you can just use it as is.

If you want to construct a typed buffer at that location, you can use placement-new to do this.

struct MyBufferType {
 //...
};

MyBufferType* buffer = reinterpret_cast<MyBufferType*>(0xdeadbee0);

void construct_buffer() {
  buffer = new (the_buffer) MyBufferType();
}