#0  0x00007ffff6ffa2a9 in raise () from /lib64/libc.so.6
#1  0x00007ffff6ffb5e8 in abort () from /lib64/libc.so.6
#2  0x00007ffff7925b45 in __gnu_debug::_Error_formatter::_M_error() const () from /usr/lib/gcc/x86_64-pc-linux-gnu/4.8.3/libstdc++.so.6
#3  0x0000000000491e90 in __gnu_debug::operator==<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > (__lhs=..., __rhs=...)
    at /usr/lib/gcc/x86_64-pc-linux-gnu/4.8.3/include/g++-v4/debug/safe_iterator.h:503
#4  0x0000000000c83ce1 in std::equal_to<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > >::operator() (this=0x1a04268, __x=..., __y=...)
    at /usr/lib/gcc/x86_64-pc-linux-gnu/4.8.3/include/g++-v4/bits/stl_function.h:208
#5  0x0000000000c82b7a in std::__detail::_Equal_helper<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > >, __gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > >, std::__detail::_Identity, std::equal_to<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > >, unsigned long, true>::_S_equals (__eq=..., __extract=..., __k=..., __c=83016128, __n=0x4f2c090) at /usr/lib/gcc/x86_64-pc-linux-gnu/4.8.3/include/g++-v4/bits/hashtable_policy.h:1166
#6  0x0000000000c812d4 in std::__detail::_Hashtable_base<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > >, __gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > >, std::__detail::_Identity, std::equal_to<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > >, list_iterator_hash, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Hashtable_traits<true, true, true> >::_M_equals (this=0x1a04268, __k=..., __c=83016128, __n=0x4f2c090)
    at /usr/lib/gcc/x86_64-pc-linux-gnu/4.8.3/include/g++-v4/bits/hashtable_policy.h:1470
#7  0x0000000000c8374b in std::_Hashtable<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > >, __gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > >, std::allocator<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > >, std::__detail::_Identity, std::equal_to<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > >, list_iterator_hash, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<true, true, true> >::_M_find_before_node (this=0x1a04268, __n=20, __k=..., __code=83016128) at /usr/lib/gcc/x86_64-pc-linux-gnu/4.8.3/include/g++-v4/bits/hashtable.h:1165
#8  0x0000000000c8271c in std::_Hashtable<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > >, __gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > >, std::allocator<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > >, std::__detail::_Identity, std::equal_to<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > >, list_iterator_hash, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<true, true, true> >::_M_find_node (this=0x1a04268, __bkt=20, __key=..., __c=83016128) at /usr/lib/gcc/x86_64-pc-linux-gnu/4.8.3/include/g++-v4/bits/hashtable.h:604
#9  0x0000000000c82937 in std::_Hashtable<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > >, __gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > >, std::allocator<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > >, std::__detail::_Identity, std::equal_to<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > >, list_iterator_hash, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<true, true, true> >::_M_insert<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > const&> (this=0x1a04268, __v=...)
    at /usr/lib/gcc/x86_64-pc-linux-gnu/4.8.3/include/g++-v4/bits/hashtable.h:1421
#10 0x0000000000c81061 in std::__detail::_Insert_base<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > >, __gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > >, std::allocator<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > >, std::__detail::_Identity, std::equal_to<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > >, list_iterator_hash, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<true, true, true> >::insert (this=0x1a04268, __v=...) at /usr/lib/gcc/x86_64-pc-linux-gnu/4.8.3/include/g++-v4/bits/hashtable_policy.h:604
#11 0x0000000000c7ef13 in std::__cxx1998::unordered_set<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > >, list_iterator_hash, std::equal_to<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > >, std::allocator<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > > >::insert (this=0x1a04268, __x=...) at /usr/lib/gcc/x86_64-pc-linux-gnu/4.8.3/include/g++-v4/bits/unordered_set.h:345
#12 0x0000000000c7d644 in std::__debug::unordered_set<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > >, list_iterator_hash, std::equal_to<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > >, std::allocator<__gnu_debug::_Safe_iterator<std::__cxx1998::_List_iterator<item>, std::__debug::list<item, std::allocator<item> > > > >::insert (this=0x1a04268, __obj=...) at /usr/lib/gcc/x86_64-pc-linux-gnu/4.8.3/include/g++-v4/debug/unordered_set:269
#13 0x0000000000c7ac87 in submap::add_active_item (this=0x19fcd40, it=..., location=...) at src/mapdata.cpp:951
#14 0x00000000009670b4 in map::add_item (this=0x7ffffff99480, x=5, y=12, new_item=..., maxitems=64) at src/map.cpp:3016
#15 0x000000000077a776 in map::rotate (this=0x7ffffff99480, turns=3) at src/mapgen.cpp:11593
#16 0x0000000000d05ffc in mapgen_rotate (m=0x7ffffff99480, terrain_type=..., north_is_down=false) at src/mapgen_functions.cpp:365
#17 0x00000000006f96b4 in mapgen_function_json::generate (this=0x23f3f00, m=0x7ffffff99480, terrain_type=..., md=..., t=28797, d=0.340000004) at src/mapgen.cpp:1028
#18 0x00000000006f9e2b in map::draw_map (this=0x7ffffff99480, terrain_type=..., t_north=..., t_east=..., t_south=..., t_west=..., t_neast=..., t_seast=..., t_nwest=..., t_swest=..., t_above=..., turn=28797,
    density=0.340000004, zlevel=0, rsettings=0x7ffff6dff178) at src/mapgen.cpp:1131
#19 0x00000000006eef9d in map::generate (this=0x7ffffff99480, x=20, y=60, z=0, turn=28797) at src/mapgen.cpp:91
#20 0x0000000000970bda in map::loadn (this=0x7ffff7f541a8, gridx=7, gridy=10, update_vehicles=true) at src/map.cpp:4632
#21 0x0000000000970162 in map::shift (this=0x7ffff7f541a8, sx=0, sy=1) at src/map.cpp:4538
#22 0x00000000005b5089 in game::update_map (this=0x7ffff7f54010, x=@0x7fffffffbf94: 61, y=@0x7fffffffbf98: 60) at src/game.cpp:13855
#23 0x00000000005adf43 in game::plmove (this=0x7ffff7f54010, dx=0, dy=1) at src/game.cpp:13138
#24 0x00000000005614a6 in game::handle_action (this=0x7ffff7f54010) at src/game.cpp:3496
#25 0x000000000054fd1c in game::do_turn (this=0x7ffff7f54010) at src/game.cpp:1423
#26 0x00000000009b8864 in main (argc=0, argv=0x7fffffffdbd0) at src/main.cpp:296