Question

I am trying to solve this error, but failed miserably. I have declared my code below

msc_con_list_slot msc_slot;
memset(&msc_slot, 0, sizeof(msc_slot));
msc_pdn_con_t*conn = &msc_slot.conn;

msc_ber_list_slot bearer_slot;
memset(&bearer_slot, 0, sizeof(bearer_slot));
msc_ber_t *bearer = &bearer_slot.bearer;

and tried to iterate it

for(&bearer_slot=(&(conn->bearers))->head; &bearer_slot; &bearer_slot=(&bearer_slot)->next)
{
//asign value here 
}

I got an error of :
lvalue required as left operand of assignment
warning: the address of ‘bearer_slot’ will always evaluate as ‘true’

Maybe I miss something, because I don’t really get what is the error actually mean is. Thank you for your help

edit add struct:

typedef struct {
        int id;
} msc_ber_t;

typedef struct _msc_ber_list_slot {
        msc_ber_t bearer;
        struct _msc_ber_list_slot *next, *prev;
} msc_ber_list_slot;

typedef struct {
        msc_ber_list_slot *head, *tail;
} msc_ber_list;

Answer 1

In the for loop, you are assigning values to &bearer_slot, that is, the address of the variable bearer_slot, which is not allowed (it is not an lvalue) and makes no sense. Furthermore, your loop condition is the value of &bearer_slot, which will always evaluate to true (as it is a non-NULL pointer), so your loop will run forever. You will need to provide more context on what you want this loop to do. By the way, (&x)->y can be written more succinctly as x.y – this would make your code a lot more readable.