Obtained 21 stack frames.
/usr/games/crawl-0.26(_Z17write_stack_traceP8_IO_FILE+0x3e) [0x5c1a810b0dde]: write_stack_trace(_IO_FILE*)
/usr/games/crawl-0.26(_Z20crash_signal_handleri+0x18f) [0x5c1a810b124f]: crash_signal_handler(int)
/lib/x86_64-linux-gnu/libc.so.6(+0x45330) [0x793deba65330]: 
/usr/games/crawl-0.26(_Z23raw_feature_descriptionB5cxx11RK9coord_def+0x6a) [0x5c1a81138d4a]: raw_feature_description[abi:cxx11](coord_def const&)
/usr/games/crawl-0.26(_Z13do_crash_dumpv+0x226b) [0x5c1a810bcfeb]: do_crash_dump()
/usr/games/crawl-0.26(_Z20crash_signal_handleri+0x1fa) [0x5c1a810b12ba]: crash_signal_handler(int)
/lib/x86_64-linux-gnu/libc.so.6(+0x45330) [0x793deba65330]: 
/lib/x86_64-linux-gnu/libc.so.6(pthread_kill+0x11c) [0x793debabeb2c]: 
/lib/x86_64-linux-gnu/libc.so.6(gsignal+0x1e) [0x793deba6527e]: 
/usr/games/crawl-0.26(+0x3f14dd) [0x5c1a810ba4dd]: 
/usr/games/crawl-0.26(_Z12AssertFailedPKcS0_iS0_z+0x1c7) [0x5c1a810baa97]: AssertFailed(char const*, char const*, int, char const*, ...)
/usr/games/crawl-0.26(_Z9save_gamebPKc+0x7dc) [0x5c1a811aa45c]: save_game(bool, char const*)
/usr/games/crawl-0.26(_Z21check_selected_skillsv+0x247) [0x5c1a81586db7]: check_selected_skills()
/usr/games/crawl-0.26(+0x4df95b) [0x5c1a811a895b]: 
/usr/games/crawl-0.26(_Z12restore_gameRKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE+0x23) [0x5c1a811a93d3]: restore_game(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)
/usr/games/crawl-0.26(_Z12startup_stepv+0xfb1) [0x5c1a815f6a01]: startup_step()
/usr/games/crawl-0.26(+0xa7a99d) [0x5c1a8174399d]: 
/usr/games/crawl-0.26(main+0x1f4) [0x5c1a81004d64]: 
/lib/x86_64-linux-gnu/libc.so.6(+0x2a1ca) [0x793deba4a1ca]: 
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0x8b) [0x793deba4a28b]: 
/usr/games/crawl-0.26(_start+0x25) [0x5c1a81005735]: