(gdb) bt full
#0  0x00007f911e0d0337 in __GI_raise (sig=sig@entry=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:55
        resultvar = 0
        pid = 56542
        selftid = 56552
#1  0x00007f911e0d1a28 in __GI_abort () at abort.c:90
        save_stage = 2
        act = {__sigaction_handler = {sa_handler = 0xd, sa_sigaction = 0xd}, sa_mask = {__val = {13, 140261296845347, 140261251435184, 13, 140261028270096, 40, 140261254898112, 13, 1, 13, 140261296845347, 140261254882176, 140261251389186, 
              696638366412715, 140261254898112, 140261254882176}}, sa_flags = 504399459, sa_restorer = 0x7fb900 <stderr>}
        sigs = {__val = {32, 0 <repeats 15 times>}}
#2  0x00007f9120c57786 in cb_assert_die (expression=expression@entry=0x58ea20 "iter != connections.conns.end()", file=file@entry=0x58e9c8 "/home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/daemon/connections.cc", line=line@entry=281)
    at /home/couchbase/jenkins/workspace/couchbase-server-unix/platform/src/cbassert.c:49
No locals.
#3  0x0000000000499434 in release_connection (c=0x7f90d3a35000) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/daemon/connections.cc:281
No locals.
#4  run_event_loop (c=0x7f90d3a35000, which=<optimized out>) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/daemon/connections.cc:157
        start = <optimized out>
        stop = <optimized out>
        ns = <optimized out>
#5  0x000000000046d0cc in thread_libevent_process (fd=<optimized out>, arg=0x7f911cc00028) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/daemon/thread.cc:338
        me = @0x7f911cc00028: <error reading variable>
        pending = {
          _M_h = {<std::__detail::_Hashtable_base<Connection*, std::pair<Connection* const, std::vector<std::pair<Cookie*, ENGINE_ERROR_CODE>, std::allocator<std::pair<Cookie*, ENGINE_ERROR_CODE> > > >, std::__detail::_Select1st, std::equal_to<Connection*>, std::hash<Connection*>, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Hashtable_traits<false, false, true> >> = {<std::__detail::_Hash_code_base<Connection*, std::pair<Connection* const, std::vector<std::pair<Cookie*, ENGINE_ERROR_CODE>, std::allocator<std::pair<Cookie*, ENGINE_ERROR_CODE> > > >, std::__detail::_Select1st, std::hash<Connection*>, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, false>> = {<std::__detail::_Hashtable_ebo_helper<0, std::__detail::_Select1st, true>> = {<std::__detail::_Select1st> = {<No data fields>}, <No data fields>}, <std::__detail::_Hashtable_ebo_helper<1, std::hash<Connection*>, true>> = {<std::hash<Connection*>> = {<std::__hash_base<unsigned long, Connection*>> = {<No data fields>}, <No data fields>}, <No data fields>}, <std::__detail::_Hashtable_ebo_helper<2, std::__detail::_Mod_range_hashing, true>> = {<std::__detail::_Mod_range_hashing> = {<No data fields>}, <No data fields>}, <No data fields>}, <std::__detail::_Hashtable_ebo_helper<0, std::equal_to<Connection*>, true>> = {<std::equal_to<Connection*>> = {<std::binary_function<Connection*, Connection*, bool>> = {<No data fields>}, <No data fields>}, <No data fields>}, <No data fields>}, <std::__detail::_Map_base<Connection*, std::pair<Connection* const, std::vector<std::pair<Cookie*, ENGINE_ERROR_CODE>, std::allocator<std::pair<Cookie*, ENGINE_ERROR_CODE> > > >, std::allocator<std::pair<Connection* const, std::vector<std::pair<Cookie*, ENGINE_ERROR_CODE>, std::allocator<std::pair<Cookie*, ENGINE_ERROR_CODE> > > > >, std::__detail::_Select1st, std::equal_to<Connection*>, std::hash<Connection*>, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<false, false, true>, true>> = {<No data fields>}, <std::__detail::_Insert<Connection*, std::pair<Connection* const, std::vector<std::pair<Cookie*, ENGINE_ERROR_CODE>, std::allocator<std::pair<Cookie*, ENGINE_ERROR_CODE> > > >, std::allocator<std::pair<Connection* const, std::vector<std::pair<Cookie*, ENGINE_ERROR_CODE>, std::allocator<std::pair<Cookie*, ENGINE_ERROR_CODE> > > > >, std::__detail::_Select1st, std::equal_to<Connection*>, std::hash<Connection*>, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<false, false, true>, false>> = {<std::__detail::_Insert_base<Connection*, std::pair<Connection* const, std::vector<std::pair<Cookie*, ENGINE_ERROR_CODE>, std::allocator<std::pair<Cookie*, ENGINE_ERROR_CODE> > > >, std::allocator<std::pair<Connection* const, std::vector<std::pair<Cookie*, ENGINE_ERROR_CODE>, std::allocator<std::pair<Cookie*, ENGINE_ERROR_CODE> > > > >, std::__detail::_Select1st, std::equal_to<Connection*>, std::hash<Connection*>, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<false, false, true> >> = {<No data fields>}, <No data fields>}, <std::__detail::_Rehash_base<Connection*, std::pair<Connection* const, std::vector<std::pair<Cookie*, ENGINE_ERROR_CODE>, std::allocator<std::pair<Cookie*, ENGINE_ERROR_CODE> > > >, std::allocator<std::pair<Connection* const, std::vector<std::pair<Cookie*, ENGINE_ERROR_CODE>, std::allocator<std::pair<Cookie*, ENGINE_ERROR_CODE> > > > >, std::__detail::_Select1st, std::equal_to<Connection*>, std::hash<Connection*>, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<false, false, true>, std::integral_constant<bool, true> >> = {<No data fields>}, <std::__detail::_Equality<Connection*, std::pair<Connection* const, std::vector<std::pair<Cookie*, ENGINE_ERROR_CODE>, std::allocator<std::pair<Cookie*, ENGINE_ERROR_CODE> > > >, std::allocator<std::pair<Connection* const, std::vector<std::pair<Cookie*, ENGINE_ERROR_CODE>, std::allocator<std::pair<Cookie*, ENGINE_ERROR_CODE> > > > >, std::__detail::_Select1st, std::equal_to<Connection*>, std::hash<Connection*>, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<false, false, true>, true>> = {<No data fields>}, <std::__detail::_Hashtable_alloc<std::allocator<std::__detail::_Hash_node<std::pair<Connection* const, std::vector<std::pair<Cookie*, ENGINE_ERROR_CODE>, std::allocator<std::pair<Cookie*, ENGINE_ERROR_CODE> > > >, false> > >> = {<std::__detail::_Hashtable_ebo_helper<0, std::allocator<std::__detail::_Hash_node<std::pair<Connection* const, std::vector<std::pair<Cookie*, ENGINE_ERROR_CODE>, std::allocator<std::pair<Cookie*, ENGINE_ERROR_CODE> > > >, false> >, true>> = {<std::allocator<std::__detail::_Hash_node<std::pair<Connection* const, std::vector<std::pair<Cookie*, ENGINE_ERROR_CODE>, std::allocator<std::pair<Cookie*, ENGINE_ERROR_CODE> > > >, false> >> = {<__gnu_cxx::new_allocator<std::__detail::_Hash_node<std::pair<Connection* const, std::vector<std::pair<Cookie*, ENGINE_ERROR_CODE>, std::allocator<std::pair<Cookie*, ENGINE_ERROR_CODE> > > >, false> >> = {<No data fields>}, <No data fields>}, <No data fields>}, <No data fields>}, _M_buckets = 0x7f9111d45740, _M_bucket_count = 3, 
            _M_before_begin = {_M_nxt = 0x7f911cc1c650}, _M_element_count = 1, _M_rehash_policy = {static _S_growth_factor = 2, _M_max_load_factor = 1, _M_next_resize = 3}, _M_single_bucket = 0x0}}
        phosphor_internal_category_enabled_301 = {_M_b = {_M_p = 0x0}}
        phosphor_internal_category_enabled_temp_301 = <optimized out>
        phosphor_internal_tpi_wait_301 = {category = 0x584085 "mutex", name = 0x58b708 "thread_libevent_process::threadLock.wait", type = phosphor::Complete, argument_names = {_M_elems = {0x5830c2 "this", 0x59e5f2 ""}}, argument_types = {_M_elems = {
              phosphor::is_pointer, phosphor::is_none}}}
        phosphor_internal_tpi_held_301 = {category = 0x584085 "mutex", name = 0x58b6d8 "thread_libevent_process::threadLock.held", type = phosphor::Complete, argument_names = {_M_elems = {0x59e5f2 "", 0x59e5f2 ""}}, argument_types = {_M_elems = {
              phosphor::is_pointer, phosphor::is_none}}}
        phosphor_internal_guard_301 = {tpiWait = 0x58b7e0 <thread_libevent_process(int, short, void*)::phosphor_internal_tpi_wait_301>, tpiHeld = 0x58b7a0 <thread_libevent_process(int, short, void*)::phosphor_internal_tpi_held_301>, enabled = true, 
          mutex = @0x7f911cc00100, threshold = {__r = 10000000}, start = {__d = {__r = 696638366410999}}, lockedAt = {__d = {__r = 696638366411799}}, releasedAt = {__d = {__r = 0}}}
        notify = {<std::_Vector_base<Connection*, std::allocator<Connection*> >> = {_M_impl = {<std::allocator<Connection*>> = {<__gnu_cxx::new_allocator<Connection*>> = {<No data fields>}, <No data fields>}, _M_start = 0x0, _M_finish = 0x0, 
              _M_end_of_storage = <optimized out>}}, <No data fields>}
#6  0x00007f911fd2b107 in event_persist_closure (ev=<optimized out>, base=0x2454860) at /home/couchbase/jenkins/workspace/cbdeps-platform-build-old/deps/packages/build/libevent/libevent-prefix/src/libevent/event.c:1580
        evcb_callback = 0x46cbb0 <thread_libevent_process(int, short, void*)>
        evcb_fd = 37
        evcb_res = 2
        evcb_arg = 0x7f911cc00028
#7  event_process_active_single_queue (base=base@entry=0x2454860, max_to_process=max_to_process@entry=2147483647, endtime=endtime@entry=0x0, activeq=<optimized out>)
    at /home/couchbase/jenkins/workspace/cbdeps-platform-build-old/deps/packages/build/libevent/libevent-prefix/src/libevent/event.c:1639
        ev = <optimized out>
        evcb = <optimized out>
        count = 1
#8  0x00007f911fd2b67f in event_process_active (base=0x2454860) at /home/couchbase/jenkins/workspace/cbdeps-platform-build-old/deps/packages/build/libevent/libevent-prefix/src/libevent/event.c:1738
        activeq = <optimized out>
---Type <return> to continue, or q <return> to quit---
        i = 0
        c = 0
        tv = {tv_sec = 140261200475760, tv_usec = 140261254989695}
        maxcb = 2147483647
        endtime = 0x0
        limit_after_prio = 2147483647
#9  event_base_loop (base=0x2454860, flags=flags@entry=0) at /home/couchbase/jenkins/workspace/cbdeps-platform-build-old/deps/packages/build/libevent/libevent-prefix/src/libevent/event.c:1961
        evsel = 0x7f911ff40bc0 <epollops>
        tv = {tv_sec = 140261145712240, tv_usec = 0}
        tv_p = <optimized out>
        res = <optimized out>
        done = 0
        retval = 0
#10 0x000000000046b209 in worker_libevent (arg=0x7f911cc00028) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/daemon/thread.cc:218
        me = @0x7f911cc00028: <error reading variable>
#11 0x00007f9120c54f17 in run (this=0x7f911cc819d0) at /home/couchbase/jenkins/workspace/couchbase-server-unix/platform/src/cb_pthreads.cc:58
No locals.
#12 platform_thread_wrap (arg=0x7f911cc819d0) at /home/couchbase/jenkins/workspace/couchbase-server-unix/platform/src/cb_pthreads.cc:71
        context = {_M_t = {
            _M_t = {<std::_Tuple_impl<0, CouchbaseThread*, std::default_delete<CouchbaseThread> >> = {<std::_Tuple_impl<1, std::default_delete<CouchbaseThread> >> = {<std::_Head_base<1, std::default_delete<CouchbaseThread>, true>> = {<std::default_delete<CouchbaseThread>> = {<No data fields>}, <No data fields>}, <No data fields>}, <std::_Head_base<0, CouchbaseThread*, false>> = {_M_head_impl = 0x7f911cc819d0}, <No data fields>}, <No data fields>}}}
#13 0x00007f911e46fe65 in start_thread (arg=0x7f9117c41700) at pthread_create.c:307
        __res = <optimized out>
        pd = 0x7f9117c41700
        now = <optimized out>
        unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140261145712384, 3532009343455218073, 0, 8392704, 0, 140261145712384, -3592156924256040551, -3592171261123868263}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, 
              cleanup = 0x0, canceltype = 0}}}
        not_first_call = <optimized out>
        pagesize_m1 = <optimized out>
        sp = <optimized out>
        freesize = <optimized out>
#14 0x00007f911e19888d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111
No locals.
(gdb)