Error C++ struct with pointer

#include <stdio.h>
#include <stdlib.h>

struct whatever{
struct whatever *next;
struct whatever *previous;
int value;
};
int main()
{
    struct whatever * node1 = (struct whatever*)malloc(sizeof(struct whatever));
    node1->value = 100;
    struct whatever * node2 = (struct whatever*)malloc(sizeof(struct whatever));
    node2->value = 200;
    node1->next = node2;
    node2->previous = node1;
...
    //release the memory
    free(node1);
    free(node2);

    return 0;
}