**Describe the bug**
https://clickhouse-test-reports.s3.yandex.net/19702/c74631c650b42e4d107254a03bd82c2c2913039b/fuzzer_msan/server.log

Most likely introduced here: #11006
{
    gatherer.gather(*this);
}
void ColumnFixedString::getExtremes(Field & min, Field & max) const
{
    min = String();
    max = String();
    size_t col_size = size();
    if (col_size == 0)
        return;
    size_t min_idx = 0;
    size_t max_idx = 0;
    less<true> less_op(*this);
    for (size_t i = 1; i < col_size; ++i)
    {
        if (less_op(i, min_idx))
            min_idx = i;
        else if (less_op(max_idx, i))
            max_idx = i;
    }
    get(min_idx, min);
    get(max_idx, max);
}
}