Intermittent failure of StreamTest.DiskBackfillFail/persistent test

/home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/kv_engine/engines/ep/src/dcp/backfill-manager.cc:140:62: runtime error: member call on address 0x621000076d00 which does not point to an object of type 'DcpConnMap'

01:38:28 0x621000076d00: note: object is of type 'ConnMap'

01:38:28  81 08 00 2f  b0 6b 2d 03 00 00 00 00  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  00 00 00 00

01:38:28               ^~~~~~~~~~~~~~~~~~~~~~~

01:38:28               vptr for 'ConnMap'

01:38:28     #0 0x1efec2d in BackfillManager::~BackfillManager() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/kv_engine/engines/ep/src/dcp/backfill-manager.cc:140

01:38:28     #1 0xf32bbc in MockDcpBackfillManager::~MockDcpBackfillManager() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/kv_engine/engines/ep/tests/mock/mock_dcp_backfill_mgr.h:26

01:38:28     #2 0xf32bbc in MockDcpBackfillManager::~MockDcpBackfillManager() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/kv_engine/engines/ep/tests/mock/mock_dcp_backfill_mgr.h:26

01:38:28     #3 0xf32621 in std::_Sp_counted_ptr<MockDcpBackfillManager*, (__gnu_cxx::_Lock_policy)2>::_M_dispose() /usr/local/include/c++/7.3.0/bits/shared_ptr_base.h:376

01:38:28     #4 0x7c2f5a in std::_Sp_counted_base<(__gnu_cxx::_Lock_policy)2>::_M_release() /usr/local/include/c++/7.3.0/bits/shared_ptr_base.h:154

01:38:28     #5 0x2014128 in std::__shared_count<(__gnu_cxx::_Lock_policy)2>::~__shared_count() /usr/local/include/c++/7.3.0/bits/shared_ptr_base.h:684

01:38:28     #6 0x2014128 in std::__shared_ptr<BackfillManager, (__gnu_cxx::_Lock_policy)2>::~__shared_ptr() /usr/local/include/c++/7.3.0/bits/shared_ptr_base.h:1123

01:38:28     #7 0x2014128 in std::__shared_ptr<BackfillManager, (__gnu_cxx::_Lock_policy)2>::reset() /usr/local/include/c++/7.3.0/bits/shared_ptr_base.h:1235

01:38:28     #8 0x2014128 in DcpProducer::~DcpProducer() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/kv_engine/engines/ep/src/dcp/producer.cc:243

01:38:28     #9 0xf32952 in MockDcpProducer::~MockDcpProducer() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/kv_engine/engines/ep/tests/mock/mock_dcp_producer.h:33

01:38:28     #10 0xf4997c in void __gnu_cxx::new_allocator<MockDcpProducer>::destroy<MockDcpProducer>(MockDcpProducer*) /usr/local/include/c++/7.3.0/ext/new_allocator.h:140

01:38:28     #11 0xf4997c in void std::allocator_traits<std::allocator<MockDcpProducer> >::destroy<MockDcpProducer>(std::allocator<MockDcpProducer>&, MockDcpProducer*) /usr/local/include/c++/7.3.0/bits/alloc_traits.h:487

01:38:28     #12 0xf4997c in std::_Sp_counted_ptr_inplace<MockDcpProducer, std::allocator<MockDcpProducer>, (__gnu_cxx::_Lock_policy)2>::_M_dispose() /usr/local/include/c++/7.3.0/bits/shared_ptr_base.h:535

01:38:28     #13 0x1e7c720 in std::_Sp_counted_base<(__gnu_cxx::_Lock_policy)2>::_M_release() /usr/local/include/c++/7.3.0/bits/shared_ptr_base.h:154

01:38:28     #14 0x1e7c720 in std::__shared_count<(__gnu_cxx::_Lock_policy)2>::~__shared_count() /usr/local/include/c++/7.3.0/bits/shared_ptr_base.h:684

01:38:28     #15 0x1e7c720 in std::__shared_ptr<ConnHandler, (__gnu_cxx::_Lock_policy)2>::~__shared_ptr() /usr/local/include/c++/7.3.0/bits/shared_ptr_base.h:1123

01:38:28     #16 0x1e7c720 in std::shared_ptr<ConnHandler>::~shared_ptr() /usr/local/include/c++/7.3.0/bits/shared_ptr.h:93

01:38:28     #17 0x1e7c720 in void std::_Destroy<std::shared_ptr<ConnHandler> >(std::shared_ptr<ConnHandler>*) /usr/local/include/c++/7.3.0/bits/stl_construct.h:98

01:38:28     #18 0x1e7c720 in void std::_Destroy_aux<false>::__destroy<std::shared_ptr<ConnHandler>*>(std::shared_ptr<ConnHandler>*, std::shared_ptr<ConnHandler>*) /usr/local/include/c++/7.3.0/bits/stl_construct.h:108

01:38:28     #19 0x1e7c720 in void std::_Destroy<std::shared_ptr<ConnHandler>*>(std::shared_ptr<ConnHandler>*, std::shared_ptr<ConnHandler>*) /usr/local/include/c++/7.3.0/bits/stl_construct.h:137

01:38:28     #20 0x1e7c720 in void std::_Destroy<std::shared_ptr<ConnHandler>*, std::shared_ptr<ConnHandler> >(std::shared_ptr<ConnHandler>*, std::shared_ptr<ConnHandler>*, std::allocator<std::shared_ptr<ConnHandler> >&) /usr/local/include/c++/7.3.0/bits/stl_construct.h:206

01:38:28     #21 0x1e7c720 in std::deque<std::shared_ptr<ConnHandler>, std::allocator<std::shared_ptr<ConnHandler> > >::_M_destroy_data_aux(std::_Deque_iterator<std::shared_ptr<ConnHandler>, std::shared_ptr<ConnHandler>&, std::shared_ptr<ConnHandler>*>, std::_Deque_iterator<std::shared_ptr<ConnHandler>, std::shared_ptr<ConnHandler>&, std::shared_ptr<ConnHandler>*>) /usr/local/include/c++/7.3.0/bits/deque.tcc:861

01:38:28     #22 0x1e68708 in std::deque<std::shared_ptr<ConnHandler>, std::allocator<std::shared_ptr<ConnHandler> > >::_M_destroy_data(std::_Deque_iterator<std::shared_ptr<ConnHandler>, std::shared_ptr<ConnHandler>&, std::shared_ptr<ConnHandler>*>, std::_Deque_iterator<std::shared_ptr<ConnHandler>, std::shared_ptr<ConnHandler>&, std::shared_ptr<ConnHandler>*>, std::allocator<std::shared_ptr<ConnHandler> > const&) /usr/local/include/c++/7.3.0/bits/stl_deque.h:2072

01:38:28     #23 0x1e68708 in std::deque<std::shared_ptr<ConnHandler>, std::allocator<std::shared_ptr<ConnHandler> > >::~deque() /usr/local/include/c++/7.3.0/bits/stl_deque.h:1045

01:38:28     #24 0x1e68708 in std::queue<std::shared_ptr<ConnHandler>, std::deque<std::shared_ptr<ConnHandler>, std::allocator<std::shared_ptr<ConnHandler> > > >::~queue() /usr/local/include/c++/7.3.0/bits/stl_queue.h:96

01:38:28     #25 0x1e68708 in AtomicQueue<std::shared_ptr<ConnHandler> >::~AtomicQueue() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/kv_engine/engines/ep/src/atomicqueue.h:39

01:38:28     #26 0x1e68708 in ConnMap::~ConnMap() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/kv_engine/engines/ep/src/connmap.cc:106

01:38:28     #27 0x1f9a019 in DcpConnMap::~DcpConnMap() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/kv_engine/engines/ep/src/dcp/dcpconnmap.cc:63

01:38:28     #28 0x1f9a182 in DcpConnMap::~DcpConnMap() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/kv_engine/engines/ep/src/dcp/dcpconnmap.cc:65

01:38:28     #29 0x2124b4a in std::default_delete<DcpConnMap>::operator()(DcpConnMap*) const /usr/local/include/c++/7.3.0/bits/unique_ptr.h:78

01:38:28     #30 0x2124b4a in std::unique_ptr<DcpConnMap, std::default_delete<DcpConnMap> >::~unique_ptr() /usr/local/include/c++/7.3.0/bits/unique_ptr.h:268

01:38:28     #31 0x2124b4a in EventuallyPersistentEngine::~EventuallyPersistentEngine() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/kv_engine/engines/ep/src/ep_engine.cc:5664

01:38:28     #32 0x212539e in EventuallyPersistentEngine::~EventuallyPersistentEngine() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/kv_engine/engines/ep/src/ep_engine.cc:5672

01:38:28     #33 0x20dbc96 in EventuallyPersistentEngine::destroy(bool) /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/kv_engine/engines/ep/src/ep_engine.cc:154

01:38:28     #34 0x111c8fb in EventuallyPersistentEngineTest::TearDown() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/kv_engine/engines/ep/tests/module_tests/evp_engine_test.cc:78

01:38:28     #35 0xffebbc in virtual thunk to StreamTest::TearDown() (/home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/build/kv_engine/ep-engine_ep_unit_tests+0xffebbc)

01:38:28     #36 0x2972d0d in void testing::internal::HandleSehExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*) /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/googletest/googletest/src/gtest.cc:2402

01:38:28     #37 0x2989369 in void testing::internal::HandleExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*) /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/googletest/googletest/src/gtest.cc:2438

01:38:28     #38 0x2948cd3 in testing::Test::Run() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/googletest/googletest/src/gtest.cc:2482

01:38:28     #39 0x2949cc9 in testing::TestInfo::Run() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/googletest/googletest/src/gtest.cc:2656

01:38:28     #40 0x294a348 in testing::TestCase::Run() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/googletest/googletest/src/gtest.cc:2774

01:38:28     #41 0x2951041 in testing::internal::UnitTestImpl::RunAllTests() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/googletest/googletest/src/gtest.cc:4649

01:38:28     #42 0x29739d3 in bool testing::internal::HandleSehExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/googletest/googletest/src/gtest.cc:2402

01:38:28     #43 0x298a9ae in bool testing::internal::HandleExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/googletest/googletest/src/gtest.cc:2438

01:38:28     #44 0x29491f6 in testing::UnitTest::Run() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/googletest/googletest/src/gtest.cc:4257

01:38:28     #45 0x1064539 in RUN_ALL_TESTS() /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/googletest/googletest/include/gtest/gtest.h:2237

01:38:28     #46 0x1064539 in main /home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/kv_engine/engines/ep/tests/module_tests/ep_unit_tests_main.cc:80

01:38:28     #47 0x7fa0e9f7882f in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2082f)

01:38:28     #48 0x7bbc88 in _start (/home/couchbase/jenkins/workspace/kv_engine-ASan-UBSan-master/build/kv_engine/ep-engine_ep_unit_tests+0x7bbc88)

01:38:28