放置新建和删除

What is the right method to delete all the memory allocated here?

  const char* charString = "Hello, World";
  void *mem = ::operator new(sizeof(Buffer) + strlen(charString) + 1);
  Buffer* buf = new(mem) Buffer(strlen(charString));

  delete (char*)buf;

或

  const char* charString = "Hello, World";
  void *mem = ::operator new(sizeof(Buffer) + strlen(charString) + 1);
  Buffer* buf = new(mem) Buffer(strlen(charString));

  delete buf;

还是两者都一样?

推荐答案

正确的方法是:

buf->~Buffer();
::operator delete(mem);

您只能使用 delete operator 删除您从 new operator 收到的内容.如果直接调用operator new函数，也必须直接调用operator delete函数，并且必须手动调用析构函数.