[ 82%] Linking CXX executable ../../bin/nerva-blockchain-export
../cryptonote_core/libcryptonote_core.a(blockchain.cpp.o): In function `cryptonote::Blockchain::get_difficulty_for_next_block()':
blockchain.cpp:(.text+0xfc43): undefined reference to `cryptonote::next_difficulty(std::vector<unsigned long, std::allocator<unsigned long> >, std::vector<unsigned long, std::allocator<unsigned long> >, unsigned long)'
../cryptonote_core/libcryptonote_core.a(blockchain.cpp.o): In function `cryptonote::Blockchain::get_next_difficulty_for_alternative_chain(std::__cxx11::list<std::__detail::_Node_iterator<std::pair<crypto::hash const, cryptonote::Blockchain::block_extended_info>, false, true>, std::allocator<std::__detail::_Node_iterator<std::pair<crypto::hash const, cryptonote::Blockchain::block_extended_info>, false, true> > > const&, unsigned long) const':
blockchain.cpp:(.text+0x1040a): undefined reference to `cryptonote::next_difficulty(std::vector<unsigned long, std::allocator<unsigned long> >, std::vector<unsigned long, std::allocator<unsigned long> >, unsigned long)'
collect2: error: ld returned 1 exit status
src/blockchain_utilities/CMakeFiles/blockchain_export.dir/build.make:190: recipe for target 'bin/nerva-blockchain-export' failed
make[2]: *** [bin/nerva-blockchain-export] Error 1
CMakeFiles/Makefile2:3011: recipe for target 'src/blockchain_utilities/CMakeFiles/blockchain_export.dir/all' failed
make[1]: *** [src/blockchain_utilities/CMakeFiles/blockchain_export.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....
[ 82%] Linking CXX executable ../../bin/nerva-blockchain-import
../cryptonote_core/libcryptonote_core.a(blockchain.cpp.o): In function `cryptonote::Blockchain::get_difficulty_for_next_block()':
blockchain.cpp:(.text+0xfc43): undefined reference to `cryptonote::next_difficulty(std::vector<unsigned long, std::allocator<unsigned long> >, std::vector<unsigned long, std::allocator<unsigned long> >, unsigned long)'
../cryptonote_core/libcryptonote_core.a(blockchain.cpp.o): In function `cryptonote::Blockchain::get_next_difficulty_for_alternative_chain(std::__cxx11::list<std::__detail::_Node_iterator<std::pair<crypto::hash const, cryptonote::Blockchain::block_extended_info>, false, true>, std::allocator<std::__detail::_Node_iterator<std::pair<crypto::hash const, cryptonote::Blockchain::block_extended_info>, false, true> > > const&, unsigned long) const':
blockchain.cpp:(.text+0x1040a): undefined reference to `cryptonote::next_difficulty(std::vector<unsigned long, std::allocator<unsigned long> >, std::vector<unsigned long, std::allocator<unsigned long> >, unsigned long)'
collect2: error: ld returned 1 exit status
src/blockchain_utilities/CMakeFiles/blockchain_import.dir/build.make:190: recipe for target 'bin/nerva-blockchain-import' failed
make[2]: *** [bin/nerva-blockchain-import] Error 1
CMakeFiles/Makefile2:2953: recipe for target 'src/blockchain_utilities/CMakeFiles/blockchain_import.dir/all' failed
make[1]: *** [src/blockchain_utilities/CMakeFiles/blockchain_import.dir/all] Error 2
Makefile:127: recipe for target 'all' failed
make: *** [all] Error 2
./2.0/builder/linux: line 36: zip: command not found