在C中动态分配的结构中使用位域是否可以？

Question

I'm going to implement a singly linked list program with bitfield in its structure, something like this:

typedef struct large
{
    unsigned number :4;
    struct large *next;
} large;

int main()
{
    large *g;
    g=(large *)malloc(sizeof(large));

    g->number=15;
    printf("%d",g->number);

    return 0;
}

---

The above program is working correctly but I read in GeeksForGeeks that,

We cannot have pointers to bit field members as they may not start at a byte boundary.

Will there be problems if I code it further for linked list implementation?

Answer 1

The pointer g in your program is a pointer to a structure variable to which you allocated memory dynamically.

g->number is not the address of the member number but its value.

You cannot have a pointer like

unsigned char *ptr=&(g->number);

you should get an error like cannot take address of bit-field

Answer 2

malloc-ing any structures including those containing bitfields is absolutely OK

 We cannot have pointers to bit field members as they may not start at a byte boundary. 

But you do not get the address of the bitfield - only for the structure itself and its size and location is always a multiple of byte.