PIDS_TICS_ALL_DELTA returns 0

Hi, I encountered an issue when using the procps library. The PIDS_TICS_ALL_DELTA value returns 0 when the PIDS_UTILIZATION_C output is commented out. When the PIDS_UTILIZATION_C output is printed, the PIDS_TICS_ALL_DELTA value returns as expected.

propc version:4.0.4

Here is my code, is something wrong?

#include <libproc2/pids.h>
#include <unistd.h>
#include <stdio.h>


int main()
{
    struct pids_info *info = NULL;
    unsigned pids[] = {getpid()};
    enum pids_item items[] = {
        PIDS_ID_PID,
        PIDS_UTILIZATION,
        PIDS_UTILIZATION_C,
        PIDS_TICS_ALL_DELTA,
    };
    enum rel_items
    {
        pid,
        utilization,
        utilization_c,
        delta,
    };

    procps_pids_new(&info, items, sizeof(items) / sizeof(items[0]));

    for (int n = 0; n < 1000000; n++)
    {

        struct pids_fetch *result = procps_pids_select(info, pids, 1, PIDS_SELECT_PID);

        for (int i = 0; i < result->counts->total; i++)
        {
            printf("PID: %lld\n", PIDS_VAL(pid, s_int, result->stacks[i], NULL));

            // if not printf utilization_c, the delta value is 0.
            printf("PIDS_UTILIZATION_C:%f\n",PIDS_VAL(utilization_c, real, result->stacks[i], NULL));
            printf("delta:%f\n", PIDS_VAL(delta, u_int, result->stacks[i], NULL));
 
        }
        procps_pids_reset(info, items, sizeof(items) / sizeof(items[0]));
    }
    procps_pids_unref(&info);

    return 0;
}