Function null_function

tests/performance/local/future_overhead.cpp:97–114

//////////////////////////////////////////////////////////////////////////

///////////////////////////////////////////////////////////////////////////////
double null_function() noexcept
{
    if (num_iterations > 0)
    {
        constexpr int array_size = 4096;
        std::array<double, array_size> dummy;
        for (std::uint64_t i = 0; i < num_iterations; ++i)
        {
            for (std::uint64_t j = 0; j < array_size; ++j)
            {
                dummy[j] = 1.0 / (2.0 * i * j + 1.0);
            }
        }
        global_scratch = dummy[0];
        return dummy[0];
    }
    return 0.0;
}

struct scratcher
{