joinGet crash for LowCardinality string

[alesapin]

SELECT joinGet('join_test', 'b', toLowCardinality('hellohellohellohell\0hellohell\0hellohellohellohellohellohell\0hellohell\0hellohellohellohellohellohell\0hellohell\0hellohellohellohellohellohell\0hellohell\0hellohello'), 1)
2020.09.24 10:23:59.446092 [ 36297 ] {} <Fatal> BaseDaemon: (version 20.10.1.1, build id: 20CB5097C4D54CF8) (from thread 20215) (query_id: 8a514d47-b48f-45c4-866f-eb0fec698ba1) Received signal Segmentation fault (11)                       
2020.09.24 10:23:59.446251 [ 36297 ] {} <Fatal> BaseDaemon: Address: NULL pointer. Access: read. Address not mapped to object.                                                                                                                 
2020.09.24 10:23:59.446405 [ 36297 ] {} <Fatal> BaseDaemon: Stack trace: 0x1171e65c 0x1172ee49 0x117229d7 0x18527323 0x18526ed3 0x18871e72 0x1887a3c6 0x1887548a 0x18872447 0x188596fb 0x1886b0a6 0x1885970d 0x188507cd 0x18853d6e 0x188569a6 0x1859f90b 0x1859c854 0x1859949b 0x1859836c 0x18898f41 0x18897a8d 0x184c2a45 0x184c196f 0x18aa1ebe 0x18aa108a 0x19400656 0x19409168 0x1d0b5a3c                                                                                                  
2020.09.24 10:23:59.452433 [ 36297 ] {} <Fatal> BaseDaemon: 4. /home/alesap/code/cpp/ClickHouse/src/Functions/IFunction.cpp:636: DB::FunctionOverloadResolverAdaptor::getReturnType(std::__1::vector<DB::ColumnWithTypeAndName, std::__1::allocator<DB::ColumnWithTypeAndName> > const&) const @ 0x1171e65c in /home/alesap/code/cpp/BuildCH/programs/clickhouse                                                                                                                              
...

Very easy to reproduce.