compile the following VCL app

g++ -I /home/vadim/vpp/build-root/install-vpp_debug-native/vpp/include main.cpp -L/home/vadim/vpp/build-root/install-vpp_debug-native/vpp/lib -lpthread -lvppcom

#include <vcl/vppcom.h>

#include <cstdio>
#include <thread>

int func()
{
    if (vppcom_worker_register() != VPPCOM_OK)
    {
        printf("failed to initialize worker");
        return 1;
    }

    return 0;
}

int main()
{
    if (vppcom_app_create("test_vcl_server") != VPPCOM_OK)
    {
        printf("failed to initialize vppcom_app");
        return 1;
    }

    std::thread thread1(func);
    thread1.join();
    vppcom_app_destroy();

    return 0;
}

vadim@vadim-lenovo:~/hybrid-ngfw/sources/pdk/network_interceptor/test_vcl_server$ sudo LD_LIBRARY_PATH=/home/vadim/vpp/build-root/install-vpp_debug-native/vpp/lib VCL_CONFIG=/home/vadim/config/vcl.conf gdb a.out
GNU gdb (Ubuntu 9.2-0ubuntu1~20.04) 9.2
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License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
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Reading symbols from a.out...
(No debugging symbols found in a.out)
(gdb) r
Starting program: /home/vadim/hybrid-ngfw/sources/pdk/network_interceptor/test_vcl_server/a.out
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
VCL<91647>: allocated VCL heap = 0x7fffe786a000, size 268435456 (0x10000000)
VCL<91647>: configured rx_fifo_size 1048576 (0x100000)
VCL<91647>: configured tx_fifo_size 1048576 (0x100000)
VCL<91647>: configured api-socket-name (/run/vpp/api.sock)
VCL<91647>: configured with mq with eventfd
VCL<91647>: configured event_queue_size 524288 (0x80000)
VCL<91647>: completed parsing vppcom config!
[New Thread 0x7fffe7869700 (LWP 91651)]
vcl_bapi_connect_to_vpp:504: vcl<91647:0>: app (test_vcl_server-wrk-0) is connected to VPP!
vcl_bapi_init:607: vcl<91647:0>: sending session enable
vppcom_app_create:1267: vcl<91647:0>: app_name 'test_vcl_server', my_client_index 512 (0x200)
[New Thread 0x7fffe7068700 (LWP 91652)]
[New Thread 0x7fffe6867700 (LWP 91653)]
vcl_bapi_connect_to_vpp:504: vcl<91647:1>: app (test_vcl_server-wrk-1) is connected to VPP!
vl_api_app_worker_add_del_reply_t_handler:227: vcl<0:-1>: worker 1 vpp-worker 1 added
vcl_worker_register_with_vpp:218: vcl<91647:1>: added worker 1
vcl_worker_cleanup_cb:145: vcl<0:-1>: cleaned up worker 1
[Thread 0x7fffe7068700 (LWP 91652) exited]
[Thread 0x7fffe7869700 (LWP 91651) exited]
^C
Thread 1 "a.out" received signal SIGINT, Interrupt.
__pthread_clockjoin_ex (threadid=140737060960000, thread_return=0x7fffffffe150, clockid=<optimized out>, abstime=<optimized out>, block=<optimized out>) at pthread_join_common.c:145
145 pthread_join_common.c: No such file or directory.
(gdb) thread apply all bt

Thread 4 (Thread 0x7fffe6867700 (LWP 91653)):
#0 futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f814202c950) at ../sysdeps/nptl/futex-internal.h:183
#1 __pthread_cond_wait_common (abstime=0x0, clockid=0, mutex=0x7f814202c900, cond=0x7f814202c928) at pthread_cond_wait.c:508
#2 __pthread_cond_wait (cond=0x7f814202c928, mutex=0x7f814202c900) at pthread_cond_wait.c:638
#3 0x00007ffff7c5928d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:82
#4 0x4000000000000000 in ?? ()
#5 0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7ffff786a780 (LWP 91647)):
#0 __pthread_clockjoin_ex (threadid=140737060960000, thread_return=0x7fffffffe150, clockid=<optimized out>, abstime=<optimized out>, block=<optimized out>) at pthread_join_common.c:145
#1 0x00007ffff7b197c1 in disconnect_from_vlib_internal (do_unmap=0 '\000') at /home/vadim/vpp/src/vlibmemory/memory_client.c:518
#2 0x00007ffff7b19827 in vl_client_disconnect_from_vlib_no_unmap () at /home/vadim/vpp/src/vlibmemory/memory_client.c:538
#3 0x00007ffff7b20aaa in vl_socket_client_disconnect2 (scm=0x7fffe786ba18) at /home/vadim/vpp/src/vlibmemory/socket_client.c:237
#4 0x00007ffff7f50569 in vcl_bapi_disconnect_from_vpp () at /home/vadim/vpp/src/vcl/vcl_bapi.c:519
#5 0x00007ffff7f39bb8 in vcl_api_detach (wrk=0x7fffe786b8c0) at /home/vadim/vpp/src/vcl/vppcom.c:1228
#6 0x00007ffff7f3a1d4 in vppcom_app_destroy () at /home/vadim/vpp/src/vcl/vppcom.c:1293
#7 0x000055555555534b in main ()
(gdb)

Actual

HANGED on exit

Expected

No hang on exit