Why can't debug static initialization block in java.util.concurrent.ConcurrentHashMap？

Question

I set breakpoints but it doesn't work. The following code cannot be debugged:

static {
    try {
        U = sun.misc.Unsafe.getUnsafe();
        Class<?> k = ConcurrentHashMap.class;
        SIZECTL = U.objectFieldOffset
            (k.getDeclaredField("sizeCtl"));
        TRANSFERINDEX = U.objectFieldOffset
            (k.getDeclaredField("transferIndex"));
        BASECOUNT = U.objectFieldOffset
            (k.getDeclaredField("baseCount"));
        CELLSBUSY = U.objectFieldOffset
            (k.getDeclaredField("cellsBusy"));
        Class<?> ck = CounterCell.class;
        CELLVALUE = U.objectFieldOffset
            (ck.getDeclaredField("value"));
        Class<?> ak = Node[].class;
        ABASE = U.arrayBaseOffset(ak);
        int scale = U.arrayIndexScale(ak);
        if ((scale & (scale - 1)) != 0)
            throw new Error("data type scale not a power of two");
        ASHIFT = 31 - Integer.numberOfLeadingZeros(scale);
    } catch (Exception e) {
        throw new Error(e);
    }
}

IDE: IntelliJ IDEA 2021.3.2 (Ultimate Edition).

The same problem occurs with AtomicInteger, but I don't know why. Can anyone explain why?