https://clickhouse-test-reports.s3.yandex.net/20492/c5b96a522e29b38eae3f6c2d945540dd234e3c34/fuzzer_msan/server.log

```
for i in {1..100}; do clickhouse-client --query "SELECT toUInt8(assumeNotNull(cast(cast(NULL, 'Nullable(String)'), 'Nullable(Enum8(\'Hello\' = 1))')))"; done

160
224
128
192
64
64
32
160
128
192
128
224
128
160
0
96
64
32
192
224
64
96
224
96
128
192
192
128
...
```
{
        const IColumn & col_from = *arguments[0].column;
        size_t size = col_from.size();
        const IDataType & data_type_to = *result_type;
        if (const ColumnString * col_from_string = checkAndGetColumn<ColumnString>(&col_from))
        {
            auto res = data_type_to.createColumn();
            IColumn & column_to = *res;
            column_to.reserve(size);
            const ColumnString::Chars & chars = col_from_string->getChars();
            const IColumn::Offsets & offsets = col_from_string->getOffsets();
            size_t current_offset = 0;
            FormatSettings format_settings;
            for (size_t i = 0; i < size; ++i)
            {
                ReadBufferFromMemory read_buffer(&chars[current_offset], offsets[i] - current_offset - 1);
                data_type_to.deserializeAsWholeText(column_to, read_buffer, format_settings);
                if (!read_buffer.eof())
                    throwExceptionForIncompletelyParsedValue(read_buffer, result_type);
                current_offset = offsets[i];
            }
            return res;
        }
        else
            throw Exception("Illegal column " + arguments[0].column->getName()
                    + " of first argument of conversion function from string",
                ErrorCodes::ILLEGAL_COLUMN);