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 IDataType * from_type = arguments[0].type.get();
        if (checkAndGetDataType<DataTypeString>(from_type))
        {
            return ConvertThroughParsing<DataTypeString, ConvertToDataType, Name, exception_mode, parsing_mode>::execute(
                arguments, result_type, input_rows_count, scale);
        }
        else if (checkAndGetDataType<DataTypeFixedString>(from_type))
        {
            return ConvertThroughParsing<DataTypeFixedString, ConvertToDataType, Name, exception_mode, parsing_mode>::execute(
                arguments, result_type, input_rows_count, scale);
        }
        return nullptr;
    }
    ColumnPtr executeImpl(const ColumnsWithTypeAndName & arguments, const DataTypePtr & result_type, size_t input_rows_count) const override