Ok got something...
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Reading symbols from nzbget.debug...done.
[New LWP 101153]
[New LWP 100764]
[New LWP 101146]
[New LWP 101147]
[New LWP 101148]
[New LWP 101162]
[New LWP 101455]
[New LWP 101648]
[New LWP 101663]
[New LWP 101664]
[New LWP 101665]
[New LWP 101666]
[New LWP 101669]
[New LWP 101670]
[New LWP 101671]
[New LWP 101672]
[New LWP 101673]
[New LWP 101674]
[New LWP 101675]
[New LWP 101676]
[New LWP 101678]
[New LWP 101679]
[New LWP 101680]
[New LWP 101681]
[New LWP 101682]
[New LWP 101684]
[New LWP 101686]
[New LWP 101687]
[New LWP 101690]
[New LWP 101691]
[New LWP 101692]
[New LWP 101693]
[New LWP 101694]
[New LWP 101695]
[New LWP 101696]
[New LWP 101697]
[New LWP 101700]
[New LWP 101142]
[New LWP 101135]
[New LWP 101155]
[New LWP 101157]
Core was generated by `./nzbget.debug -c nzbget.conf -s -o outputmode=log'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 x86_64_freebsd_fallback_frame_state (context=0x804600de0, context=0x804600de0, fs=0x804600b30) at ./md-unwind-support.h:60
60 ./md-unwind-support.h: No such file or directory.
[Current thread is 1 (LWP 101153)]
(gdb) bt
#0 x86_64_freebsd_fallback_frame_state (context=0x804600de0, context=0x804600de0, fs=0x804600b30) at ./md-unwind-support.h:60
#1 uw_frame_state_for (context=context@entry=0x804600de0, fs=fs@entry=0x804600b30) at ../../../gcc-5.3.0/libgcc/unwind-dw2.c:1249
#2 0x00000000008954db in _Unwind_ForcedUnwind_Phase2 (exc=exc@entry=0x8034afdf0, context=context@entry=0x804600de0) at ../../../gcc-5.3.0/libgcc/unwind.inc:155
#3 0x0000000000895b54 in _Unwind_ForcedUnwind (exc=0x8034afdf0, stop=0x57d1a0 <thread_unwind_stop>, stop_argument=<optimized out>)
at ../../../gcc-5.3.0/libgcc/unwind.inc:207
#4 0x000000000057d38c in _pthread_exit_mask ()
#5 0x000000000057d3ab in pthread_exit ()
#6 0x000000000057b36c in thread_start ()
#7 0x0000000804401000 in ?? ()
Backtrace stopped: Cannot access memory at address 0x804601000