gdb -ex=run  --args /usr/sbin/accel-pppd  -p /var/run/accel-pppd.pid -c /etc/accel-ppp.conf

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Reading symbols from /usr/sbin/accel-pppd...
Starting program: /usr/sbin/accel-pppd -p /var/run/accel-pppd.pid -c /etc/accel-ppp.conf
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7ffff760a640 (LWP 242110)]
[New Thread 0x7ffff6dfa640 (LWP 242111)]
[New Thread 0x7ffff65f9640 (LWP 242112)]
[New Thread 0x7ffff5d75640 (LWP 244002)]
[New Thread 0x7ffff5c74640 (LWP 244003)]
[New Thread 0x7ffff5b73640 (LWP 244004)]
[New Thread 0x7ffff5a72640 (LWP 244005)]
[New Thread 0x7ffff5971640 (LWP 244006)]
[New Thread 0x7ffff5170640 (LWP 244007)]

Thread 7 "accel-pppd" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7ffff5b73640 (LWP 244004)]
0x00007ffff77d36b9 in __list_add (new=0x7fffe00a20d8, prev=0x278608b331fc000, next=0x7fffec0f52b0) at /opt/accel-ppp-code/accel-pppd/include/list.h:47
47prev->next = new;
(gdb) bt fullbt full

#0  0x00007ffff77d36b9 in __list_add (new=0x7fffe00a20d8, prev=0x278608b331fc000, next=0x7fffec0f52b0)
    at /opt/accel-ppp-code/accel-pppd/include/list.h:47
No locals.
#1  0x00007ffff77d370d in list_add_tail (new=0x7fffe00a20d8, head=0x7fffec0f52b0) at /opt/accel-ppp-code/accel-pppd/include/list.h:73
No locals.
#2  0x00007ffff77d46e6 in fail_log (t=0x7ffff77d8280 <fail_log_target>, msg=0x7fffe00a20d8, ses=0x7fffec11cf60)
    at /opt/accel-ppp-code/accel-pppd/logs/log_file.c:358
        fpd = 0x7fffec0f5298
#3  0x00005555555874ba in do_log (level=5, fmt=0x55555558bc1c "ccp_layer_free\n", ap=0x7ffff5b72860, ses=0x7fffec11cf60)
    at /opt/accel-ppp-code/accel-pppd/log.c:109
        t = 0x7ffff77d8280 <fail_log_target>
        m = 0x7fffe00a20d8
#4  0x0000555555587ff9 in log_ppp_debug (fmt=0x55555558bc1c "ccp_layer_free\n") at /opt/accel-ppp-code/accel-pppd/log.c:230
        ap = {{gp_offset = 8, fp_offset = 48, overflow_arg_area = 0x7ffff5b72940, reg_save_area = 0x7ffff5b72880}}
#5  0x000055555557317b in ccp_layer_free (ld=0x7fffe4520b88) at /opt/accel-ppp-code/accel-pppd/ppp/ppp_ccp.c:184
        ccp = 0x7fffe4520b88
#6  0x0000555555563c32 in _free_layers (ppp=0x7fffec11cf60) at /opt/accel-ppp-code/accel-pppd/ppp/ppp.c:707
        n = 0x7fffe0137c98
        d = 0x7fffe4520b88
#7  0x0000555555562319 in destroy_ppp_channel (ppp=0x7fffec11cf60) at /opt/accel-ppp-code/accel-pppd/ppp/ppp.c:227
No locals.
#8  0x000055555556258b in destablish_ppp (ppp=0x7fffec11cf60) at /opt/accel-ppp-code/accel-pppd/ppp/ppp.c:268
        uc = 0x0
#9  0x0000555555563556 in ppp_terminate (ses=0x7fffec11cf60, hard=1) at /opt/accel-ppp-code/accel-pppd/ppp/ppp.c:593
        ppp = 0x7fffec11cf60
        n = 0x7fffe452efe8
        d = 0x321c05090
        s = 0
#10 0x000055555555ddb8 in ap_session_terminate (ses=0x7fffec11cf60, cause=1, hard=0) at /opt/accel-ppp-code/accel-pppd/session.c:298
No locals.
#11 0x000055555556833c in lcp_recv (h=0x7fffe452efc0) at /opt/accel-ppp-code/accel-pppd/ppp/ppp_lcp.c:821
        hdr = 0x7fffe04450c8
        lcp = 0x7fffe452ef98
        r = 32767
        term_msg = 0x5555555ce1e8 "\210\342\\UUU"
#12 0x0000555555562c96 in ppp_chan_read (h=0x7fffec11d0c0) at /opt/accel-ppp-code/accel-pppd/ppp/ppp.c:424
        ppp = 0x7fffec11cf60
        ppp_h = 0x7fffe452efc0
        proto = 49185
#13 0x00007ffff7fb228a in ctx_thread (ctx=0x7fffec19c628) at /opt/accel-ppp-code/accel-pppd/triton/triton.c:252
        h = 0x7fffe015b0c8
        t = 0x7fffec11cf60
        call = 0x7fffec11cf60
        tt = 140737153978072
        events = 1
#14 0x00007ffff7fb201e in triton_thread (thread=0x555555606de8) at /opt/accel-ppp-code/accel-pppd/triton/triton.c:192
        set = {__val = {516, 0 <repeats 15 times>}}
        sig = 10
        need_free = 0
        stack = 0x0
#15 0x00007ffff7891ac3 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:442
        ret = <optimized out>
        pd = <optimized out>
        out = <optimized out>
        unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140737488346896, 8002429504245508911, 140737315812928, 2, 140737346344912, 140737488347248,
                -8002408001985533137, -8002412553186923729}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0,
--Type <RET> for more, q to quit, c to continue without paging--c

              cleanup = 0x0, canceltype = 0}}}
        not_first_call = <optimized out>
#16 0x00007ffff7923850 in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81
No locals.