In file included from /usr/include/c++/5/algorithm:62:0,
                 from /in/foo.cc:2:
/usr/include/c++/5/bits/stl_algo.h: In instantiation of 'void std::__insertion_sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]':
/usr/include/c++/5/bits/stl_algo.h:1880:25:   required from 'void std::__final_insertion_sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]'
/usr/include/c++/5/bits/stl_algo.h:1966:31:   required from 'void std::__sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]'
/usr/include/c++/5/bits/stl_algo.h:4698:18:   required from 'void std::sort(_RAIter, _RAIter) [with _RAIter = int]'
/in/foo.cc:18:25:   required from here
/usr/include/c++/5/bits/stl_algo.h:1845:3: error: no type named 'value_type' in 'struct std::iterator_traits<int>'
   __val = _GLIBCXX_MOVE(*__i);
   ^
/usr/include/c++/5/bits/stl_algo.h:1847:8: error: invalid type argument of unary '*' (have 'int')
        *__first = _GLIBCXX_MOVE(__val);
        ^
/usr/include/c++/5/bits/stl_algo.h:1845:3: error: no type named 'value_type' in 'struct std::iterator_traits<int>'
   __val = _GLIBCXX_MOVE(*__i);
   ^
In file included from /usr/include/c++/5/bits/stl_algobase.h:71:0,
                 from /usr/include/c++/5/bits/char_traits.h:39,
                 from /usr/include/c++/5/ios:40,
                 from /usr/include/c++/5/ostream:38,
                 from /usr/include/c++/5/iostream:39,
                 from /in/foo.cc:1:
/usr/include/c++/5/bits/predefined_ops.h: In instantiation of 'bool __gnu_cxx::__ops::_Iter_less_iter::operator()(_Iterator1, _Iterator2) const [with _Iterator1 = int; _Iterator2 = int]':
/usr/include/c++/5/bits/stl_algo.h:1842:14:   required from 'void std::__insertion_sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]'
/usr/include/c++/5/bits/stl_algo.h:1880:25:   required from 'void std::__final_insertion_sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]'
/usr/include/c++/5/bits/stl_algo.h:1966:31:   required from 'void std::__sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]'
/usr/include/c++/5/bits/stl_algo.h:4698:18:   required from 'void std::sort(_RAIter, _RAIter) [with _RAIter = int]'
/in/foo.cc:18:25:   required from here
/usr/include/c++/5/bits/predefined_ops.h:43:16: error: invalid type argument of unary '*' (have 'int')
       { return *__it1 < *__it2; }
                ^
/usr/include/c++/5/bits/predefined_ops.h:43:25: error: invalid type argument of unary '*' (have 'int')
       { return *__it1 < *__it2; }
                         ^
In file included from /usr/include/c++/5/bits/stl_algo.h:61:0,
                 from /usr/include/c++/5/algorithm:62,
                 from /in/foo.cc:2:
/usr/include/c++/5/bits/stl_heap.h: In instantiation of 'void std::__make_heap(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]':
/usr/include/c++/5/bits/stl_algo.h:1669:23:   required from 'void std::__heap_select(_RandomAccessIterator, _RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]'
/usr/include/c++/5/bits/stl_algo.h:1928:25:   required from 'void std::__partial_sort(_RandomAccessIterator, _RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]'
/usr/include/c++/5/bits/stl_algo.h:1943:27:   required from 'void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = int; _Size = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]'
/usr/include/c++/5/bits/stl_algo.h:1963:25:   required from 'void std::__sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]'
/usr/include/c++/5/bits/stl_algo.h:4698:18:   required from 'void std::sort(_RAIter, _RAIter) [with _RAIter = int]'
/in/foo.cc:18:25:   required from here
/usr/include/c++/5/bits/stl_heap.h:321:4: error: no type named 'value_type' in 'struct std::iterator_traits<int>'
    _ValueType;
    ^
/usr/include/c++/5/bits/stl_heap.h:323:4: error: no type named 'difference_type' in 'struct std::iterator_traits<int>'
    _DistanceType;
    ^
/usr/include/c++/5/bits/stl_heap.h: In instantiation of 'void std::__pop_heap(_RandomAccessIterator, _RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]':
/usr/include/c++/5/bits/stl_algo.h:1672:19:   required from 'void std::__heap_select(_RandomAccessIterator, _RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]'
/usr/include/c++/5/bits/stl_algo.h:1928:25:   required from 'void std::__partial_sort(_RandomAccessIterator, _RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]'
/usr/include/c++/5/bits/stl_algo.h:1943:27:   required from 'void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIterator = int; _Size = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]'
/usr/include/c++/5/bits/stl_algo.h:1963:25:   required from 'void std::__sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]'
/usr/include/c++/5/bits/stl_algo.h:4698:18:   required from 'void std::sort(_RAIter, _RAIter) [with _RAIter = int]'
/in/foo.cc:18:25:   required from here
/usr/include/c++/5/bits/stl_heap.h:239:2: error: no type named 'value_type' in 'struct std::iterator_traits<int>'
  _ValueType;
  ^
/usr/include/c++/5/bits/stl_heap.h:241:2: error: no type named 'difference_type' in 'struct std::iterator_traits<int>'
  _DistanceType;
  ^
/usr/include/c++/5/bits/stl_heap.h:244:7: error: invalid type argument of unary '*' (have 'int')
       *__result = _GLIBCXX_MOVE(*__first);
       ^
In file included from /usr/include/c++/5/bits/stl_pair.h:59:0,
                 from /usr/include/c++/5/bits/stl_algobase.h:64,
                 from /usr/include/c++/5/bits/char_traits.h:39,
                 from /usr/include/c++/5/ios:40,
                 from /usr/include/c++/5/ostream:38,
                 from /usr/include/c++/5/iostream:39,
                 from /in/foo.cc:1:
/usr/include/c++/5/bits/stl_heap.h:244:19: error: invalid type argument of unary '*' (have 'int')
       *__result = _GLIBCXX_MOVE(*__first);
                   ^
In file included from /usr/include/c++/5/bits/char_traits.h:39:0,
                 from /usr/include/c++/5/ios:40,
                 from /usr/include/c++/5/ostream:38,
                 from /usr/include/c++/5/iostream:39,
                 from /in/foo.cc:1:
/usr/include/c++/5/bits/stl_algobase.h: In instantiation of 'void std::iter_swap(_ForwardIterator1, _ForwardIterator2) [with _ForwardIterator1 = int; _ForwardIterator2 = int]':
/usr/include/c++/5/bits/stl_algo.h:84:20:   required from 'void std::__move_median_to_first(_Iterator, _Iterator, _Iterator, _Iterator, _Compare) [with _Iterator = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]'
/usr/include/c++/5/bits/stl_algo.h:1916:34:   required from '_RandomAccessIterator std::__unguarded_partition_pivot(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = int; _Compare = __gnu_cxx::__ops::_Iter_less_iter]'
/usr/include/c++/5/bits/stl_algo.h:1948:38:   required from 'void std::__introsort_loop(_RandomAccessIterator, _RandomAccessIterator, _Size, _Compare) [with _RandomAccessIte