Thread: Volatile, nested structs

I can't figure out why I get "warning: assignment discards qualifiers from pointer target type" when I do this:

Code:

struct b_struct {
    int *data;
};

static volatile struct a_struct {
    struct b_struct b;
    int data[10];
} a;


int main(void)
{
    volatile struct b_struct b;
    b.data = a.data; /* This line gives a warning. */
    return 0;
}

b.data is “volatile pointer to int”, a.data is “array of volatile int” which turns into “pointer to volatile int”.

That is, with the array of int, each int is volatile. With the pointer, the pointer itself is volatile.