Server is dying after groupArrayArray of Array(LowCardinality(String))

[stovmasyan89]

Steps to reproduce:

SET allow_experimental_low_cardinality_type = 1;

CREATE TABLE test.table1
(
dt Date,
id Int32,
arr Array(LowCardinality(String))
) ENGINE = MergeTree PARTITION BY toMonday(dt)
ORDER BY (dt, id) SETTINGS index_granularity = 8192;

CREATE TABLE test.table2
(
dt Date,
id Int32,
arr Array(LowCardinality(String))
) ENGINE = MergeTree PARTITION BY toMonday(dt)
ORDER BY (dt, id) SETTINGS index_granularity = 8192;

insert into test.table1 (dt, id, arr)
values (toDate(now()), 1, ['aaa']);
insert into test.table2 (dt, id, arr)
values (toDate(now()), 1, ['aaa','bbb','ccc']);

select dt,
id,
groupArrayArray(arr)
from (
select dt, id, arr
from test.table1
where dt = today()
and id = 1
UNION ALL
select dt, id, arr
from test.table2
where dt = today()
and id = 1
)
group by dt, id

[filimonov]

STacktrace:

2019.01.11 15:43:58.038811 [ 2 ] {} <Error> BaseDaemon: ########################################
2019.01.11 15:43:58.038876 [ 2 ] {} <Error> BaseDaemon: (from thread 229) Received signal Segmentation fault (11).
2019.01.11 15:43:58.038897 [ 2 ] {} <Error> BaseDaemon: Address: 0x11
2019.01.11 15:43:58.038912 [ 2 ] {} <Error> BaseDaemon: Access: read.
2019.01.11 15:43:58.038925 [ 2 ] {} <Error> BaseDaemon: Address not mapped to object.
2019.01.11 15:43:58.071560 [ 2 ] {} <Error> BaseDaemon: 0. clickhouse-server(memcpy+0x250) [0x6348220]
2019.01.11 15:43:58.071707 [ 2 ] {} <Error> BaseDaemon: 1. clickhouse-server(DB::GroupArrayGeneralListImpl<DB::GroupArrayListNodeString, false>::add(char*, DB::IColumn const**, unsigned long, DB::Arena*) const+0xa6) [0x490d6e6]
2019.01.11 15:43:58.071728 [ 2 ] {} <Error> BaseDaemon: 2. clickhouse-server(DB::IAggregateFunctionHelper<DB::AggregateFunctionArray>::addFree(DB::IAggregateFunction const*, char*, DB::IColumn const**, unsigned long, DB::Arena*)+0xfb) [0x48eb46b]
2019.01.11 15:43:58.071766 [ 2 ] {} <Error> BaseDaemon: 3. clickhouse-server(void DB::Aggregator::executeImplCase<false, DB::AggregationMethodKeysFixed<HashMapTable<DB::UInt128, HashMapCell<DB::UInt128, char*, DB::UInt128HashCRC32, HashTableNoState>, DB::UInt128HashCRC32, HashTableGrower<8ul>, Allocator<true> >, false, false> >(DB::AggregationMethodKeysFixed<HashMapTable<DB::UInt128, HashMapCell<DB::UInt128, char*, DB::UInt128HashCRC32, HashTableNoState>, DB::UInt128HashCRC32, HashTableGrower<8ul>, Allocator<true> >, false, false>&, DB::AggregationMethodKeysFixed<HashMapTable<DB::UInt128, HashMapCell<DB::UInt128, char*, DB::UInt128HashCRC32, HashTableNoState>, DB::UInt128HashCRC32, HashTableGrower<8ul>, Allocator<true> >, false, false>::State&, DB::Arena*, unsigned long, std::vector<DB::IColumn const*, std::allocator<DB::IColumn const*> >&, DB::Aggregator::AggregateFunctionInstruction*, std::vector<StringRef, std::allocator<StringRef> >&, char*) const+0x218) [0x52ec2c8]
2019.01.11 15:43:58.071797 [ 2 ] {} <Error> BaseDaemon: 4. clickhouse-server(void DB::Aggregator::executeImpl<DB::AggregationMethodKeysFixed<HashMapTable<DB::UInt128, HashMapCell<DB::UInt128, char*, DB::UInt128HashCRC32, HashTableNoState>, DB::UInt128HashCRC32, HashTableGrower<8ul>, Allocator<true> >, false, false> >(DB::AggregationMethodKeysFixed<HashMapTable<DB::UInt128, HashMapCell<DB::UInt128, char*, DB::UInt128HashCRC32, HashTableNoState>, DB::UInt128HashCRC32, HashTableGrower<8ul>, Allocator<true> >, false, false>&, DB::Arena*, unsigned long, std::vector<DB::IColumn const*, std::allocator<DB::IColumn const*> >&, DB::Aggregator::AggregateFunctionInstruction*, std::vector<StringRef, std::allocator<StringRef> >&, bool, char*) const+0x5b) [0x52ec5eb]
2019.01.11 15:43:58.071828 [ 2 ] {} <Error> BaseDaemon: 5. clickhouse-server(DB::Aggregator::executeOnBlock(DB::Block const&, DB::AggregatedDataVariants&, std::vector<DB::IColumn const*, std::allocator<DB::IColumn const*> >&, std::vector<std::vector<DB::IColumn const*, std::allocator<DB::IColumn const*> >, std::allocator<std::vector<DB::IColumn const*, std::allocator<DB::IColumn const*> > > >&, std::vector<StringRef, std::allocator<StringRef> >&, bool&)+0xe56) [0x5275586]
2019.01.11 15:43:58.071843 [ 2 ] {} <Error> BaseDaemon: 6. clickhouse-server(DB::ParallelAggregatingBlockInputStream::Handler::onBlock(DB::Block&, unsigned long)+0x5c) [0x522224c]
2019.01.11 15:43:58.071855 [ 2 ] {} <Error> BaseDaemon: 7. clickhouse-server(DB::ParallelInputsProcessor<DB::ParallelAggregatingBlockInputStream::Handler>::thread(std::shared_ptr<DB::ThreadGroupStatus>, unsigned long)+0x34a) [0x5228d4a]
2019.01.11 15:43:58.071873 [ 2 ] {} <Error> BaseDaemon: 8. clickhouse-server(std::thread::_State_impl<std::thread::_Invoker<std::tuple<DB::ParallelInputsProcessor<DB::ParallelAggregatingBlockInputStream::Handler>::process()::{lambda()#1}> > >::_M_run()+0x40) [0x52294d0]
2019.01.11 15:43:58.071910 [ 2 ] {} <Error> BaseDaemon: 9. clickhouse-server() [0x6a7fa8f]
2019.01.11 15:43:58.071920 [ 2 ] {} <Error> BaseDaemon: 10. /lib64/libpthread.so.0(+0x7e25) [0x7fa97c380e25]
2019.01.11 15:43:58.071940 [ 2 ] {} <Error> BaseDaemon: