typedef unsigned long long uint64_t;
void f(uint64_t *a, uint64_t aa) __attribute__((noinline));
void f(uint64_t *a, uint64_t aa) {
    uint64_t new_value = aa;
    uint64_t old_value = *a;
    int bit_size = 32;
    uint64_t mask = (uint64_t)(unsigned)(-1);
    uint64_t tmp = old_value & mask;
    new_value &= mask;
    /* On overflow we need to add 1 in the upper bits */
    if (tmp > new_value)
        new_value += 1ull << bit_size;
    /* Add in the upper bits from the old value */
    new_value += old_value & ~mask;
    *a = new_value;
}
int main(void) {
    uint64_t value, new_value, old_value;
    value = 0x100000001;
    old_value = value;
    new_value = (value + 1) & (uint64_t)(unsigned)(-1);
    f(&value, new_value);
    if (value != old_value + 1)
        __builtin_abort();
    return 0;
}
