Comment 3 for bug 1767124

That would be because you failed to apply a workaround for bug 994921. It might require some tweaking :/

But lucky for you we did get enough info from the crash file:

Stacktrace:
 #0 agent_get (owner=owner@entry=0x0) at src/agent.c:267
         agent = <optimized out>
 #1 0x000055922049561b in adapter_register (adapter=0x559220a77c20) at src/adapter.c:7434
         agent = <optimized out>
         db = <optimized out>
 #2 read_info_complete (status=<optimized out>, length=<optimized out>, param=<optimized out>, user_data=0x559220a77c20) at src/adapter.c:7897
         adapter = 0x559220a77c20
         rp = <optimized out>
         missing_settings = <optimized out>
         __func__ = "read_info_complete"
 #3 0x00005592204bf656 in request_complete (mgmt=mgmt@entry=0x559220a71d90, status=<optimized out>, opcode=opcode@entry=4, index=index@entry=0, length=length@entry=280, param=0x559220a72d29) at src/shared/mgmt.c:261
         match = {opcode = 4, index = 0}
         request = 0x559220a72fb0
 #4 0x00005592204c011c in can_read_data (io=<optimized out>, user_data=0x559220a71d90) at src/shared/mgmt.c:353
         hdr = <optimized out>
         cc = 0x559220a72d26
         cs = <optimized out>
         opcode = 4
         event = <optimized out>
         index = <optimized out>
         length = 283
 #5 0x00005592204cbe25 in watch_callback (channel=<optimized out>, cond=<optimized out>, user_data=<optimized out>) at src/shared/io-glib.c:170
         watch = <optimized out>
         result = <optimized out>
         destroy = <optimized out>
 #6 0x00007f310746b04a in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
 No symbol table info available.
 #7 0x00007f310746b3f0 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
 No symbol table info available.
 #8 0x00007f310746b712 in g_main_loop_run () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
 No symbol table info available.
 #9 0x000055922042d09d in main (argc=1, argv=0x7ffe83a0edb8) at src/main.c:687
         context = <optimized out>
         err = 0x0
         sdp_flags = <optimized out>
         gdbus_flags = <optimized out>
         watchdog = 0
         watchdog_usec = <optimized out>
         __func__ = "main"
StacktraceAddressSignature: /usr/lib/bluetooth/bluetoothd:4:/usr/lib/bluetooth/bluetoothd+8461b:/usr/lib/bluetooth/bluetoothd+ae656:/usr/lib/bluetooth/bluetoothd+af11c:/usr/lib/bluetooth/bluetoothd+bae25:/lib/x86_64-linux-gnu/libglib-2.0.so.0.4800.2+4a04a:/lib/x86_64-linux-gnu/libglib-2.0.so.0.4800.2+4a3f0:/lib/x86_64-linux-gnu/libglib-2.0.so.0.4800.2+4a712:/usr/lib/bluetooth/bluetoothd+1c09d
StacktraceTop:
 agent_get (owner=owner@entry=0x0) at src/agent.c:267
 adapter_register (adapter=0x559220a77c20) at src/adapter.c:7434
 read_info_complete (status=<optimized out>, length=<optimized out>, param=<optimized out>, user_data=0x559220a77c20) at src/adapter.c:7897
 request_complete (mgmt=mgmt@entry=0x559220a71d90, status=<optimized out>, opcode=opcode@entry=4, index=index@entry=0, length=length@entry=280, param=0x559220a72d29) at src/shared/mgmt.c:261
 can_read_data (io=<optimized out>, user_data=0x559220a71d90) at src/shared/mgmt.c:353
Tags: xenial third-party-packages
ThreadStacktrace:
 .
 Thread 1 (Thread 0x7f3107894880 (LWP 23334)):
 #0 agent_get (owner=owner@entry=0x0) at src/agent.c:267
         agent = <optimized out>
 #1 0x000055922049561b in adapter_register (adapter=0x559220a77c20) at src/adapter.c:7434
         agent = <optimized out>
         db = <optimized out>
 #2 read_info_complete (status=<optimized out>, length=<optimized out>, param=<optimized out>, user_data=0x559220a77c20) at src/adapter.c:7897
         adapter = 0x559220a77c20
         rp = <optimized out>
         missing_settings = <optimized out>
         __func__ = "read_info_complete"
 #3 0x00005592204bf656 in request_complete (mgmt=mgmt@entry=0x559220a71d90, status=<optimized out>, opcode=opcode@entry=4, index=index@entry=0, length=length@entry=280, param=0x559220a72d29) at src/shared/mgmt.c:261
         match = {opcode = 4, index = 0}
         request = 0x559220a72fb0
 #4 0x00005592204c011c in can_read_data (io=<optimized out>, user_data=0x559220a71d90) at src/shared/mgmt.c:353
         hdr = <optimized out>
         cc = 0x559220a72d26
         cs = <optimized out>
         opcode = 4
         event = <optimized out>
         index = <optimized out>
         length = 283
 #5 0x00005592204cbe25 in watch_callback (channel=<optimized out>, cond=<optimized out>, user_data=<optimized out>) at src/shared/io-glib.c:170
         watch = <optimized out>
         result = <optimized out>
         destroy = <optimized out>
 #6 0x00007f310746b04a in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
 No symbol table info available.
 #7 0x00007f310746b3f0 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
 No symbol table info available.
 #8 0x00007f310746b712 in g_main_loop_run () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
 No symbol table info available.
 #9 0x000055922042d09d in main (argc=1, argv=0x7ffe83a0edb8) at src/main.c:687
         context = <optimized out>
         err = 0x0
         sdp_flags = <optimized out>
         gdbus_flags = <optimized out>
         watchdog = 0
         watchdog_usec = <optimized out>
         __func__ = "main"