error: no viable conversion from       'cryptonote::difficulty_type'
```
home/mwo2/onion-monero-blockchain-explorer/src/page.h:1294:14: error: no viable conversion from
      'cryptonote::difficulty_type' (aka 'number<cpp_int_backend<128, 128, unsigned_magnitude,
      unchecked, void> >') to 'uint64_t' (aka 'unsigned long')
    uint64_t blk_difficulty = core_storage->get_db().get_block_difficulty(_blk_height);
             ^                ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /home/mwo2/onion-monero-blockchain-explorer/main.cpp:4:
In file included from /home/mwo2/onion-monero-blockchain-explorer/src/page.h:12:
In file included from /home/mwo2/onion-monero-blockchain-explorer/src/monero_headers.h:24:
In file included from /home/mwo2/monero/src/cryptonote_core/tx_pool.h:44:
In file included from /home/mwo2/monero/src/cryptonote_basic/cryptonote_basic_impl.h:33:
In file included from /home/mwo2/monero/src/cryptonote_basic/cryptonote_basic.h:41:
/home/mwo2/monero/src/serialization/binary_archive.h:194:28: warning: shift count >= width of type
      [-Wshift-count-overflow]
      if (1 < sizeof(T)) v >>= 8;
                           ^   ~
/home/mwo2/monero/src/serialization/binary_archive.h:187:5: note: in instantiation of function
      template specialization 'binary_archive<true>::serialize_uint<unsigned char>' requested here
    serialize_uint(static_cast<typename boost::make_unsigned<T>::type>(v));
    ^
/home/mwo2/monero/src/serialization/binary_archive.h:227:5: note: in instantiation of function
      template specialization 'binary_archive<true>::serialize_int<unsigned char>' requested here
    serialize_int(t);
    ^
1 warning and 1 error generated.
make[2]: *** [CMakeFiles/xmrblocks.dir/build.make:63: CMakeFiles/xmrblocks.dir/main.cpp.o] Error 1
make[1]: *** [CMakeFiles/Makefile2:75: CMakeFiles/xmrblocks.dir/all] Error 2
make: *** [Makefile:84: all] Error 2
```