Obtained 27 stack frames.
/usr/games/crawl-git-381ce9d8e6(_Z17write_stack_traceP8_IO_FILE+0x3e) [0x571e9f71881e]: write_stack_trace(_IO_FILE*)
/usr/games/crawl-git-381ce9d8e6(_Z20crash_signal_handleri+0x18f) [0x571e9f718c8f]: crash_signal_handler(int)
/lib/x86_64-linux-gnu/libc.so.6(+0x42910) [0x7f5cc8042910]: 
/usr/games/crawl-git-381ce9d8e6(_Z13handle_hangupi+0) [0x571e9f9d7680]: handle_hangup(int)
/lib/x86_64-linux-gnu/libc.so.6(+0x42910) [0x7f5cc8042910]: 
/lib/x86_64-linux-gnu/libc.so.6(wait4+0x15) [0x7f5cc810fbf5]: 
/usr/games/crawl-git-381ce9d8e6(_Z8call_gdbP8_IO_FILE+0xec) [0x571e9f718ecc]: call_gdb(_IO_FILE*)
/usr/games/crawl-git-381ce9d8e6(_Z13do_crash_dumpv+0x458) [0x571e9f726998]: do_crash_dump()
/usr/games/crawl-git-381ce9d8e6(_Z20crash_signal_handleri+0x1fa) [0x571e9f718cfa]: crash_signal_handler(int)
/lib/x86_64-linux-gnu/libc.so.6(+0x42910) [0x7f5cc8042910]: 
/usr/games/crawl-git-381ce9d8e6(_ZN5actor9knockbackERKS_iiNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE+0x133) [0x571e9f68a723]: actor::knockback(actor const&, int, int, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >)
/usr/games/crawl-git-381ce9d8e6(_ZN4bolt15knockback_actorEP5actori+0xf6) [0x571e9f6c8636]: bolt::knockback_actor(actor*, int)
/usr/games/crawl-git-381ce9d8e6(_ZN4bolt13affect_playerEv+0x4cf) [0x571e9f6cb32f]: bolt::affect_player()
/usr/games/crawl-git-381ce9d8e6(_ZN4bolt11affect_cellEv+0x2d6) [0x571e9f6cc126]: bolt::affect_cell()
/usr/games/crawl-git-381ce9d8e6(_ZN4bolt7do_fireEv+0x750) [0x571e9f6d3fc0]: bolt::do_fire()
/usr/games/crawl-git-381ce9d8e6(_ZN4bolt4fireEv+0x278) [0x571e9f6d49b8]: bolt::fire()
/usr/games/crawl-git-381ce9d8e6(_Z16handle_mon_spellP7monster+0x974) [0x571e9fac3824]: handle_mon_spell(monster*)
/usr/games/crawl-git-381ce9d8e6(+0x80e57a) [0x571e9fa8757a]: 
/usr/games/crawl-git-381ce9d8e6(_Z19handle_monster_moveP7monster+0x4b6) [0x571e9fa8bea6]: handle_monster_move(monster*)
/usr/games/crawl-git-381ce9d8e6(_Z15handle_monstersb+0xc28) [0x571e9fa8ed88]: handle_monsters(bool)
/usr/games/crawl-git-381ce9d8e6(_Z12world_reactsv+0x14f) [0x571e9fe880ef]: world_reacts()
/usr/games/crawl-git-381ce9d8e6(+0xc11446) [0x571e9fe8a446]: 
/usr/games/crawl-git-381ce9d8e6(+0xc12145) [0x571e9fe8b145]: 
/usr/games/crawl-git-381ce9d8e6(main+0x1f7) [0x571e9f6518c7]: 
/lib/x86_64-linux-gnu/libc.so.6(+0x280d0) [0x7f5cc80280d0]: 
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0x89) [0x7f5cc8028189]: 
/usr/games/crawl-git-381ce9d8e6(_start+0x25) [0x571e9f6522e5]: