add8
static void add8(secret uint8_t *, size_t, const secret uint8_t *, size_t);
add8(D->V, sizeof D->V, w, sizeof w);
add8(D->V, sizeof D->V, H, sizeof H);
add8(D->V, sizeof D->V, D->C, sizeof D->C);
add8(D->V, sizeof D->V, reseed_counter, sizeof reseed_counter);
add8(data, sizeof data, (const uint8_t[]) {1}, 1);