https://clickhouse-test-reports.s3.yandex.net/19475/02d28c1f9b9558ca5af267167a542819b9e1d061/fuzzer_debug/report.html#fail1
{
        size_t pos = impl.getRow() + 1;
        for (; pos < impl.rows; ++pos)
            if (!samePrev(pos))
                break;
        return pos - impl.getRow();
    }
    
    bool ALWAYS_INLINE samePrev(size_t lhs_pos) const
    {
        for (size_t i = 0; i < impl.sort_columns_size; ++i)
            if (impl.sort_columns[i]->compareAt(lhs_pos - 1, lhs_pos, *(impl.sort_columns[i]), 1) != 0)
                return false;
        return true;
    }
};
namespace
{
MutableColumns makeMutableColumns(const Block & block, size_t rows_to_reserve = 0)