(gdb) bt full
#0  __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at ./nptl/pthread_kill.c:44
        tid = <optimized out>
        ret = 0
        pd = <optimized out>
        old_mask = {__val = {0}}
        ret = <optimized out>
#1  0x00007fc6354a815f in __pthread_kill_internal (signo=6, threadid=<optimized out>) at ./nptl/pthread_kill.c:78
No locals.
#2  0x00007fc63545a472 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
        ret = <optimized out>
#3  0x00007fc6354444b2 in __GI_abort () at ./stdlib/abort.c:79
        save_stage = 1
        act = {__sigaction_handler = {sa_handler = 0x20, sa_sigaction = 0x20}, sa_mask = {__val = {0 <repeats 13 times>, 7167589996808792434, 7503118402219671557, 0}}, sa_flags = 797308496, sa_restorer = 0x7fc62a6eaa60}
#4  0x00007fc6326a89ab in __gnu_cxx::__verbose_terminate_handler () at /tmp/deploy/objdir/../gcc-13.2.0/libstdc++-v3/libsupc++/vterminate.cc:95
        terminating = false
        t = <optimized out>
#5  0x0000000000c61e66 in backtrace_terminate_handler () at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/utilities/terminate_handler.cc:88
No locals.
#6  0x00007fc6326b82fa in __cxxabiv1::__terminate (handler=<optimized out>) at /tmp/deploy/objdir/../gcc-13.2.0/libstdc++-v3/libsupc++/eh_terminate.cc:48
No locals.
#7  0x00007fc6326b8365 in std::terminate () at /tmp/deploy/objdir/../gcc-13.2.0/libstdc++-v3/libsupc++/eh_terminate.cc:58
No locals.
#8  0x00007fc6326b8608 in __cxxabiv1::__cxa_rethrow () at /tmp/deploy/objdir/../gcc-13.2.0/libstdc++-v3/libsupc++/eh_throw.cc:136
        globals = <optimized out>
        header = <optimized out>
#9  0x0000000000d45c3e in __cxxabiv1::__cxa_rethrow () at /home/couchbase/jenkins/cbdeps-ws/deps/packages/build/folly/folly-prefix/src/folly/folly/experimental/exception_tracer/ExceptionTracerLib.cpp:119
        orig_cxa_rethrow = 0x0
#10 0x000000000053d605 in log_handled_exception () at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/utilities/terminate_handler.cc:39
        tried_throw = 0
#11 backtrace_terminate_handler () at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/utilities/terminate_handler.cc:79
No locals.
#12 0x00007fc6326b82fa in __cxxabiv1::__terminate (handler=<optimized out>) at /tmp/deploy/objdir/../gcc-13.2.0/libstdc++-v3/libsupc++/eh_terminate.cc:48
No locals.
#13 0x00007fc6326b8365 in std::terminate () at /tmp/deploy/objdir/../gcc-13.2.0/libstdc++-v3/libsupc++/eh_terminate.cc:58
No locals.
#14 0x00007fc6326b9063 in __cxxabiv1::__cxa_pure_virtual () at /tmp/deploy/objdir/../gcc-13.2.0/libstdc++-v3/libsupc++/pure.cc:50
No locals.
#15 0x000000000060cd6e in Connection::to_json[abi:cxx11]() const (this=0x7fc62d5fcd80) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/daemon/connection.cc:226
        ret = {m_type = nlohmann::json_abi_v3_11_2::detail::value_t::object, m_value = {object = 0x7fc62cfa9e70, array = 0x7fc62cfa9e70, string = 0x7fc62cfa9e70, binary = 0x7fc62cfa9e70, boolean = 112, number_integer = 140489134874224, 
            number_unsigned = 140489134874224, number_float = 6.9410855155311474e-310}}
        features = {m_type = nlohmann::json_abi_v3_11_2::detail::value_t::array, m_value = {object = 0x7fc62d171440, array = 0x7fc62d171440, string = 0x7fc62d171440, binary = 0x7fc62d171440, boolean = 64, number_integer = 140489136739392, 
            number_unsigned = 140489136739392, number_float = 6.9410856076826906e-310}}
        arr = {m_type = nlohmann::json_abi_v3_11_2::detail::value_t::array, m_value = {object = 0x7fc62d188fa0, array = 0x7fc62d188fa0, string = 0x7fc62d188fa0, binary = 0x7fc62d188fa0, boolean = 160, number_integer = 140489136836512, 
            number_unsigned = 140489136836512, number_float = 6.9410856124810562e-310}}
        value = 868257070
#16 0x0000000000627432 in Cookie::~Cookie (this=0x7fc62d22f000, __in_chrg=<optimized out>) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/daemon/cookie.cc:775
        _logger_ = 0x7fc62f85f650
        _logger_ = <optimized out>
#17 0x0000000000627519 in Cookie::~Cookie (this=0x7fc62d22f000, __in_chrg=<optimized out>) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/daemon/cookie.cc:785
        _logger_ = <optimized out>
#18 0x000000000060750f in std::default_delete<Cookie>::operator() (__ptr=<optimized out>, this=<optimized out>) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/unique_ptr.h:99
No locals.
#19 std::unique_ptr<Cookie, std::default_delete<Cookie> >::~unique_ptr (this=0x7fc54f03ce00, __in_chrg=<optimized out>) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/unique_ptr.h:404
        __ptr = <error reading variable: Cannot access memory at address 0x7fc54f03ce00>
#20 std::_Destroy<std::unique_ptr<Cookie, std::default_delete<Cookie> > > (__pointer=0x7fc54f03ce00) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/stl_construct.h:151
No locals.
#21 std::_Destroy_aux<false>::__destroy<std::unique_ptr<Cookie, std::default_delete<Cookie> >*> (__last=<optimized out>, __first=0x7fc54f03ce00) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/stl_construct.h:163
No locals.
#22 std::_Destroy<std::unique_ptr<Cookie, std::default_delete<Cookie> >*> (__last=<optimized out>, __first=<optimized out>) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/stl_construct.h:196
No locals.
#23 std::_Destroy<std::unique_ptr<Cookie, std::default_delete<Cookie> >*, std::unique_ptr<Cookie, std::default_delete<Cookie> > > (__last=<optimized out>, __first=<optimized out>) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/alloc_traits.h:947
No locals.
#24 std::deque<std::unique_ptr<Cookie, std::default_delete<Cookie> >, std::allocator<std::unique_ptr<Cookie, std::default_delete<Cookie> > > >::_M_destroy_data_aux (this=<optimized out>, __last=..., __first=...)
    at /opt/gcc-13.2.0/include/c++/13.2.0/bits/deque.tcc:875
--Type <RET> for more, q to quit, c to continue without paging--
No locals.
#25 std::deque<std::unique_ptr<Cookie, std::default_delete<Cookie> >, std::allocator<std::unique_ptr<Cookie, std::default_delete<Cookie> > > >::_M_destroy_data (this=0x7fc62d5fcdc8, __first=..., __last=...)
    at /opt/gcc-13.2.0/include/c++/13.2.0/bits/stl_deque.h:2091
No locals.
#26 std::deque<std::unique_ptr<Cookie, std::default_delete<Cookie> >, std::allocator<std::unique_ptr<Cookie, std::default_delete<Cookie> > > >::~deque (this=0x7fc62d5fcdc8, __in_chrg=<optimized out>)
    at /opt/gcc-13.2.0/include/c++/13.2.0/bits/stl_deque.h:1028
No locals.
#27 Connection::~Connection (this=this@entry=0x7fc62d5fcd80, __in_chrg=<optimized out>) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/daemon/connection.cc:1263
No locals.
#28 0x000000000061cd6c in LibeventConnection::~LibeventConnection (this=0x7fc62d5fcd80, __in_chrg=<optimized out>) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/daemon/connection_libevent.cc:76
No locals.
#29 LibeventConnection::~LibeventConnection (this=0x7fc62d5fcd80, __in_chrg=<optimized out>) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/daemon/connection_libevent.cc:76
No locals.
#30 0x00000000005cf7e4 in std::default_delete<Connection>::operator() (__ptr=<optimized out>, this=<optimized out>) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/unique_ptr.h:99
No locals.
#31 std::unique_ptr<Connection, std::default_delete<Connection> >::~unique_ptr (this=0x7fc62fd00290, __in_chrg=<optimized out>) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/unique_ptr.h:404
        __ptr = <error reading variable: Cannot access memory at address 0x7fc62fd00290>
#32 std::pair<Connection* const, std::unique_ptr<Connection, std::default_delete<Connection> > >::~pair (this=0x7fc62fd00288, __in_chrg=<optimized out>) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/stl_pair.h:187
No locals.
#33 std::__new_allocator<std::__detail::_Hash_node<std::pair<Connection* const, std::unique_ptr<Connection, std::default_delete<Connection> > >, false> >::destroy<std::pair<Connection* const, std::unique_ptr<Connection, std::default_delete<Connection> > > > (__p=0x7fc62fd00288, this=<synthetic pointer>) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/new_allocator.h:194
No locals.
#34 std::allocator_traits<std::allocator<std::__detail::_Hash_node<std::pair<Connection* const, std::unique_ptr<Connection, std::default_delete<Connection> > >, false> > >::destroy<std::pair<Connection* const, std::unique_ptr<Connection, std::default_delete<Connection> > > > (__p=0x7fc62fd00288, __a=<synthetic pointer>...) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/alloc_traits.h:557
No locals.
#35 std::_Node_handle_common<std::pair<Connection* const, std::unique_ptr<Connection, std::default_delete<Connection> > >, std::allocator<std::__detail::_Hash_node<std::pair<Connection* const, std::unique_ptr<Connection, std::default_delete<Connection> > >, false> > >::_M_reset (this=<synthetic pointer>) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/node_handle.h:166
        __alloc = <optimized out>
        __alloc = <optimized out>
#36 std::_Node_handle_common<std::pair<Connection* const, std::unique_ptr<Connection, std::default_delete<Connection> > >, std::allocator<std::__detail::_Hash_node<std::pair<Connection* const, std::unique_ptr<Connection, std::default_delete<Connection> > >, false> > >::~_Node_handle_common (this=<synthetic pointer>, __in_chrg=<optimized out>) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/node_handle.h:89
No locals.
#37 std::_Node_handle<Connection*, std::pair<Connection* const, std::unique_ptr<Connection, std::default_delete<Connection> > >, std::allocator<std::__detail::_Hash_node<std::pair<Connection* const, std::unique_ptr<Connection, std::default_delete<Connection> > >, false> > >::~_Node_handle (this=<synthetic pointer>, __in_chrg=<optimized out>) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/node_handle.h:243
No locals.
#38 FrontEndThread::destroy_connection (this=<optimized out>, connection=...) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/daemon/thread.cc:332
        node = {<std::_Node_handle_common<std::pair<Connection* const, std::unique_ptr<Connection, std::default_delete<Connection> > >, std::allocator<std::__detail::_Hash_node<std::pair<Connection* const, std::unique_ptr<Connection, std::default_delete<Connection> > >, false> > >> = {_M_ptr = 0x7fc62fd00280, _M_alloc = {_M_empty = {<No data fields>}, 
              _M_alloc = {<std::__new_allocator<std::__detail::_Hash_node<std::pair<Connection* const, std::unique_ptr<Connection, std::default_delete<Connection> > >, false> >> = {<No data fields>}, <No data fields>}}}, _M_pkey = 0x7fc62fd00288, 
          _M_pmapped = <optimized out>}
#39 0x000000000061e9ea in LibeventConnection::read_callback (this=0x7fc62d5fcd80) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/daemon/connection_libevent.cc:136
        phosphor_internal_category_enabled_130 = {_M_b = {_M_p = 0x0}}
        phosphor_internal_category_enabled_temp_130 = <optimized out>
        phosphor_internal_tpi_wait_130 = {category = 0xe3dd0d "mutex", name = 0xde0d18 "LibeventConnection::read_callback::threadLock.wait", type = phosphor::TraceEventType::Complete, argument_names = {_M_elems = {0xe3a7cd "this", 0xe3e723 ""}}, 
          argument_types = {_M_elems = {phosphor::TraceArgumentType::is_pointer, phosphor::TraceArgumentType::is_none}}}
        phosphor_internal_tpi_held_130 = {category = 0xe3dd0d "mutex", name = 0xde0ce0 "LibeventConnection::read_callback::threadLock.held", type = phosphor::TraceEventType::Complete, argument_names = {_M_elems = {0xe3e723 "", 0xe3e723 ""}}, 
          argument_types = {_M_elems = {phosphor::TraceArgumentType::is_pointer, phosphor::TraceArgumentType::is_none}}}
        phosphor_internal_guard_130 = {tpiWait = 0xe4f220 <LibeventConnection::read_callback()::phosphor_internal_tpi_wait_130>, tpiHeld = 0xe4f1e0 <LibeventConnection::read_callback()::phosphor_internal_tpi_held_130>, enabled = true, 
          mutex = @0x7fc62fd58ee0, threshold = {__r = 10000000}, start = {__d = {__r = 7497502325363639}}, lockedAt = {__d = {__r = 7497502325364227}}, releasedAt = {__d = {__r = 0}}}
#40 0x00007fc633c0f84e in bufferevent_run_deferred_callbacks_unlocked (cb=<optimized out>, arg=0x7fc62d5fb980) at /home/couchbase/jenkins/cbdeps-ws/deps/packages/build/libevent/libevent-prefix/src/libevent/bufferevent.c:208
        readcb = 0x61ebb0 <LibeventConnection::read_callback(bufferevent*, void*)>
        cbarg = 0x7fc62d5fcd80
        bufev_private = 0x7fc62d5fb980
        bufev = 0x7fc62d5fb980
#41 0x00007fc633c18b99 in event_process_active_single_queue (base=base@entry=0x7fc62f865200, activeq=0x7fc6303ec0e0, max_to_process=max_to_process@entry=2147483647, endtime=endtime@entry=0x0)
    at /home/couchbase/jenkins/cbdeps-ws/deps/packages/build/libevent/libevent-prefix/src/libevent/event.c:1726
        evcb_cbfinalize = <optimized out>
        ev = <optimized out>
        evcb = 0x7fc62d5fbb20
        count = 2
#42 0x00007fc633c19287 in event_process_active (base=0x7fc62f865200) at /home/couchbase/jenkins/cbdeps-ws/deps/packages/build/libevent/libevent-prefix/src/libevent/event.c:1789
        activeq = <optimized out>
        i = 0
        c = 0
--Type <RET> for more, q to quit, c to continue without paging--
        tv = {tv_sec = 0, tv_usec = 140489092149504}
        maxcb = 2147483647
        endtime = 0x0
        limit_after_prio = 2147483647
        activeq = <optimized out>
        i = <optimized out>
        c = <optimized out>
        endtime = <optimized out>
        tv = <optimized out>
        maxcb = <optimized out>
        limit_after_prio = <optimized out>
        done = <optimized out>
#43 event_base_loop (base=0x7fc62f865200, flags=flags@entry=1) at /home/couchbase/jenkins/cbdeps-ws/deps/packages/build/libevent/libevent-prefix/src/libevent/event.c:2012
        n = <optimized out>
        evsel = 0x7fc633e2cc20 <epollops>
        tv = {tv_sec = 0, tv_usec = 0}
        tv_p = <optimized out>
        res = <optimized out>
        done = 0
        retval = 0
        __func__ = "event_base_loop"
#44 0x0000000000d7bcc6 in (anonymous namespace)::EventBaseBackend::eb_event_base_loop (flags=1, this=<optimized out>) at /home/couchbase/jenkins/cbdeps-ws/deps/packages/build/folly/folly-prefix/src/folly/folly/io/async/EventBase.cpp:74
No locals.
#45 folly::EventBase::loopBody (this=this@entry=0x7fc62fd58c80, flags=flags@entry=0, ignoreKeepAlive=ignoreKeepAlive@entry=false) at /home/couchbase/jenkins/cbdeps-ws/deps/packages/build/folly/folly-prefix/src/folly/folly/io/async/EventBase.cpp:381
        callbacks = {<boost::intrusive::list_impl<boost::intrusive::bhtraits<folly::EventBase::LoopCallback, boost::intrusive::list_node_traits<void*>, (boost::intrusive::link_mode_type)2, boost::intrusive::dft_tag, 1>, unsigned long, false, void>> = {
            static constant_time_size = false, static stateful_value_traits = <optimized out>, static has_container_from_iterator = <optimized out>, static safemode_or_autounlink = true, 
            data_ = {<boost::intrusive::bhtraits<folly::EventBase::LoopCallback, boost::intrusive::list_node_traits<void*>, (boost::intrusive::link_mode_type)2, boost::intrusive::dft_tag, 1>> = {<boost::intrusive::bhtraits_base<folly::EventBase::LoopCallback, boost::intrusive::list_node<void*>*, boost::intrusive::dft_tag, 1>> = {<No data fields>}, static link_mode = boost::intrusive::auto_unlink}, root_plus_size_ = {<boost::intrusive::detail::size_holder<false, unsigned long, void>> = {
                  static constant_time_size = <optimized out>}, m_header = {<boost::intrusive::list_node<void*>> = {next_ = 0x7fc62a6eb0a0, prev_ = 0x7fc62a6eb0a0}, <No data fields>}}}}, <No data fields>}
        message = 0xe2ba38 "Your code just tried to loop over an event base from inside another event base loop. Since libevent is not reentrant, this leads to undefined behavior in opt builds. Please fix immediately. For the co"...
        SCOPE_EXIT_STATE8 = {<folly::detail::ScopeGuardImplBase> = {dismissed_ = false}, function_ = {__this = 0x7fc62fd58c80}}
        res = 0
        ranLoopCallbacks = <optimized out>
        blocking = true
        once = false
        prev = {__d = {__r = 7497294903795535}}
        idleStart = {__d = {__r = 7497502325356900}}
        busy = <optimized out>
        idle = <optimized out>
        prevLoopThread = {_M_thread = 0}
#46 0x0000000000d7c1ce in folly::EventBase::loop (this=this@entry=0x7fc62fd58c80) at /home/couchbase/jenkins/cbdeps-ws/deps/packages/build/folly/folly-prefix/src/folly/folly/io/async/EventBase.cpp:305
        guard = {list_ = {prev = 0x11ee8a0 <folly::emptyList>, curr = {forbid = true, allowTerminationOnBlocking = false, ex = 0x7fc62fd58c90, tag = {static npos = <optimized out>, b_ = 0x0, e_ = 0x0}}}}
#47 0x0000000000d7e698 in folly::EventBase::loopForever (this=this@entry=0x7fc62fd58c80) at /home/couchbase/jenkins/cbdeps-ws/deps/packages/build/folly/folly-prefix/src/folly/folly/io/async/EventBase.cpp:524
        SCOPE_EXIT_STATE9 = <optimized out>
        SCOPE_EXIT_STATE10 = <optimized out>
        ret = <optimized out>
#48 0x00000000005cf0d9 in worker_libevent (arg=0x7fc62fd58c70) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/daemon/thread.cc:272
        me = <error reading variable: Cannot access memory at address 0x7fc62fd58c70>
#49 0x0000000000cce91c in std::function<void ()>::operator()() const (this=0x7fc62fd07838) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/std_function.h:591
No locals.
#50 operator() (__closure=0x7fc62fd07818) at /home/couchbase/jenkins/workspace/couchbase-server-unix/platform/src/thread.cc:117
        main = <error reading variable main (Cannot access memory at address 0x7fc62fd07838)>
        n = <error reading variable n (Cannot access memory at address 0x7fc62fd07818)>
        main = <optimized out>
        n = <optimized out>
#51 std::__invoke_impl<void, create_thread(std::function<void()>, std::string)::<lambda()> > (__f=...) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/invoke.h:61
No locals.
#52 std::__invoke<create_thread(std::function<void()>, std::string)::<lambda()> > (__fn=...) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/invoke.h:96
No locals.
#53 std::thread::_Invoker<std::tuple<create_thread(std::function<void()>, std::string)::<lambda()> > >::_M_invoke<0> (this=0x7fc62fd07818) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/std_thread.h:292
No locals.
#54 std::thread::_Invoker<std::tuple<create_thread(std::function<void()>, std::string)::<lambda()> > >::operator() (this=0x7fc62fd07818) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/std_thread.h:299
No locals.
#55 std::thread::_State_impl<std::thread::_Invoker<std::tuple<create_thread(std::function<void()>, std::string)::<lambda()> > > >::_M_run(void) (this=0x7fc62fd07810) at /opt/gcc-13.2.0/include/c++/13.2.0/bits/std_thread.h:244
--Type <RET> for more, q to quit, c to continue without paging--
No locals.
#56 0x00007fc6326e4aa3 in std::execute_native_thread_routine (__p=0x7fc62fd07810) at /tmp/deploy/objdir/../gcc-13.2.0/libstdc++-v3/src/c++11/thread.cc:104
        __t = <optimized out>
#57 0x00007fc6354a63ec in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:444
        ret = <optimized out>
        pd = <optimized out>
        out = <optimized out>
        unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140489274319152, 5557518730196469383, -40320, 0, 140720678532080, 140489083801600, -5572059902401001849, -5572026670628944249}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {
              prev = 0x0, cleanup = 0x0, canceltype = 0}}}
        not_first_call = <optimized out>
#58 0x00007fc635526a4c in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81
No locals.
(gdb)