Unable to compile 0.16.0rc2 for aarch64

[vertyclank]

System: Ubuntu 16.04 64bit in Virtualbox (all up to date, all dependencies met) (this exact procedure works to compile bitcoin-0.20.1)

====Procedure for compile====

Download https://github.com/vertcoin-project/vertcoin-core/archive/0.16.0-rc2.zip

Unzip

unzip 0.16.0-rc2.zip

cd into directory

vertcoin-core-0.16.0-rc2

cd into depends

cd depends

make folder for the arch

mkdir aarch64-linux-gnu

cd back into vertcoin-core-0.16.0-rc2

cd ../

Run autogen.sh

./autogen.sh

Run ./configure command

./configure --prefix=$PWD/depends/aarch64-linux-gnu --disable-wallet --without-gui --without-miniupnpc

Run make command

make HOST=aarch64-linux-gnu

'make' command finishes with this error (ERROR ENCOUNTERED HERE)

//usr/lib/x86_64-linux-gnu/libboost_system.so.1.58.0: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
Makefile:7907: recipe for target 'vertcoind' failed
make[2]: *** [vertcoind] Error 1
make[2]: Leaving directory '/home/vertyclank/Downloads/vertcoin-core-0.16.0-rc2/src'
Makefile:17240: recipe for target 'all-recursive' failed
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory '/home/vertyclank/Downloads/vertcoin-core-0.16.0-rc2/src'
Makefile:781: recipe for target 'all-recursive' failed
make: *** [all-recursive] Error 1

This is the entire output of the command

node@buildvm:~/Downloads/vertcoin-core-0.16.0-rc2$ make HOST=aarch64-linux-gnu

make[1]: Entering directory '/home/vertyclank/Downloads/vertcoin-core-0.16.0-rc2/src'
make[2]: Entering directory '/home/vertyclank/Downloads/vertcoin-core-0.16.0-rc2/src'
  CXX      support/libbitcoinconsensus_la-cleanse.lo
  CXX      crypto/libbitcoinconsensus_la-aes.lo
  CXX      crypto/libbitcoinconsensus_la-chacha_poly_aead.lo
  CXX      crypto/libbitcoinconsensus_la-chacha20.lo
  CXX      crypto/libbitcoinconsensus_la-hkdf_sha256_32.lo
  CXX      crypto/libbitcoinconsensus_la-hmac_sha256.lo
  CXX      crypto/libbitcoinconsensus_la-hmac_sha512.lo
  CXX      crypto/libbitcoinconsensus_la-poly1305.lo
  CXX      crypto/libbitcoinconsensus_la-ripemd160.lo
  CXX      crypto/libbitcoinconsensus_la-sha1.lo
  CXX      crypto/libbitcoinconsensus_la-sha256.lo
  CXX      crypto/libbitcoinconsensus_la-sha512.lo
  CXX      crypto/libbitcoinconsensus_la-scrypt.lo
crypto/scrypt.cpp: In function ‘void scrypt_N_1_1_256(const char*, char*, unsigned char)’:
crypto/scrypt.cpp:248:52: warning: variable length array ‘scratchpad’ is used [-Wvla]
  char scratchpad[((1 << (Nfactor + 1)) * 128 ) + 63];
                                                    ^
crypto/scrypt.cpp:246:6: warning: stack protector not protecting local variables: variable length buffer [-Wstack-protector]
 void scrypt_N_1_1_256(const char *input, char *output, unsigned char Nfactor)
      ^
In file included from ./util/system.h:22:0,
                 from crypto/scrypt.cpp:34:
./optional.h: At global scope:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      crypto/libbitcoinconsensus_la-scrypt-sse2.lo
  CC       crypto/Lyra2RE/libbitcoinconsensus_la-Lyra2RE.lo
  CC       crypto/Lyra2RE/libbitcoinconsensus_la-Lyra2.lo
  CC       crypto/Lyra2RE/libbitcoinconsensus_la-Sponge.lo
  CC       crypto/Lyra2RE/libbitcoinconsensus_la-blake.lo
  CC       crypto/Lyra2RE/libbitcoinconsensus_la-groestl.lo
  CC       crypto/Lyra2RE/libbitcoinconsensus_la-keccak.lo
  CC       crypto/Lyra2RE/libbitcoinconsensus_la-skein.lo
  CC       crypto/Lyra2RE/libbitcoinconsensus_la-cubehash.lo
  CC       crypto/Lyra2RE/libbitcoinconsensus_la-bmw.lo
  CXX      crypto/libbitcoinconsensus_la-siphash.lo
  CXX      crypto/libbitcoinconsensus_la-verthash_datfile.lo
In file included from ./util/system.h:22:0,
                 from ./crypto/verthash_datfile.h:13,
                 from crypto/verthash_datfile.cpp:1:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CC       crypto/tiny_sha3/libbitcoinconsensus_la-sha3.lo
  CXX      crypto/libbitcoinconsensus_la-verthash.lo
crypto/verthash.cpp: In static member function ‘static void Verthash::Hash(const char*, char*)’:
crypto/verthash.cpp:128:68: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result]
                 fread(&value, sizeof(uint32_t), 1, VerthashDatFile);
                                                                    ^
crypto/verthash.cpp:150:32: warning: ‘VerthashDatFile’ may be used uninitialized in this function [-Wmaybe-uninitialized]
         fclose(VerthashDatFile);
                                ^
In file included from ./util/system.h:22:0,
                 from ./crypto/verthash.h:12,
                 from crypto/verthash.cpp:1:
./optional.h: At global scope:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      crypto/libbitcoinconsensus_la-sha256_sse4.lo
  CXX      libbitcoinconsensus_la-arith_uint256.lo
  CXX      consensus/libbitcoinconsensus_la-merkle.lo
  CXX      consensus/libbitcoinconsensus_la-tx_check.lo
  CXX      libbitcoinconsensus_la-hash.lo
  CXX      primitives/libbitcoinconsensus_la-block.lo
In file included from ./util/system.h:22:0,
                 from ./crypto/verthash.h:12,
                 from primitives/block.cpp:13:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      primitives/libbitcoinconsensus_la-transaction.lo
  CXX      libbitcoinconsensus_la-pubkey.lo
  CXX      script/libbitcoinconsensus_la-bitcoinconsensus.lo
  CXX      script/libbitcoinconsensus_la-interpreter.lo
  CXX      script/libbitcoinconsensus_la-script.lo
  CXX      script/libbitcoinconsensus_la-script_error.lo
  CXX      libbitcoinconsensus_la-uint256.lo
  CXX      util/libbitcoinconsensus_la-strencodings.lo
make[3]: Entering directory '/home/vertyclank/Downloads/vertcoin-core-0.16.0-rc2/src/secp256k1'
gcc -I. -g -O2 -Wall -Wextra -Wno-unused-function -c src/gen_context.c -o gen_context.o
gcc -g -O2 -Wall -Wextra -Wno-unused-function  gen_context.o -o gen_context
./gen_context
  CC       src/libsecp256k1_la-secp256k1.lo
  CCLD     libsecp256k1.la
/usr/bin/ar: `u' modifier ignored since `D' is the default (see `U')
make[3]: Leaving directory '/home/vertyclank/Downloads/vertcoin-core-0.16.0-rc2/src/secp256k1'
  CXXLD    libbitcoinconsensus.la
/usr/bin/ar: `u' modifier ignored since `D' is the default (see `U')
  CXX      vertcoind-bitcoind.o
  CXX      libbitcoin_server_a-addrdb.o
In file included from ./util/system.h:22:0,
                 from ./addrman.h:15,
                 from addrdb.cpp:8:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-addrman.o
In file included from ./util/system.h:22:0,
                 from ./addrman.h:15,
                 from addrman.cpp:6:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-banman.o
In file included from ./util/system.h:22:0,
                 from banman.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-blockencodings.o
In file included from ./txmempool.h:20:0,
                 from blockencodings.cpp:13:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-blockfilter.o
  CXX      libbitcoin_server_a-chain.o
  CXX      consensus/libbitcoin_server_a-tx_verify.o
  CXX      libbitcoin_server_a-flatfile.o
In file included from ./util/system.h:22:0,
                 from flatfile.cpp:11:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-httprpc.o
In file included from ./util/system.h:22:0,
                 from httprpc.cpp:14:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-httpserver.o
In file included from ./util/system.h:22:0,
                 from httpserver.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      index/libbitcoin_server_a-base.o
In file included from ./util/system.h:22:0,
                 from ./dbwrapper.h:12,
                 from ./index/base.h:8,
                 from index/base.cpp:6:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      index/libbitcoin_server_a-blockfilterindex.o
In file included from ./util/system.h:22:0,
                 from ./dbwrapper.h:12,
                 from index/blockfilterindex.cpp:7:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      index/libbitcoin_server_a-txindex.o
In file included from ./util/system.h:22:0,
                 from ./dbwrapper.h:12,
                 from ./index/base.h:8,
                 from ./index/txindex.h:9,
                 from index/txindex.cpp:5:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      interfaces/libbitcoin_server_a-chain.o
  CXX      interfaces/libbitcoin_server_a-node.o
  CXX      libbitcoin_server_a-init.o
  CXX      libbitcoin_server_a-dbwrapper.o
In file included from ./util/system.h:22:0,
                 from ./dbwrapper.h:12,
                 from dbwrapper.cpp:5:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-miner.o
  CXX      libbitcoin_server_a-net.o
In file included from ./util/system.h:22:0,
                 from ./addrman.h:15,
                 from ./net.h:10,
                 from net.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-net_processing.o
In file included from ./util/system.h:22:0,
                 from ./addrman.h:15,
                 from ./net.h:10,
                 from ./net_processing.h:10,
                 from net_processing.cpp:6:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      node/libbitcoin_server_a-coin.o
In file included from ./txmempool.h:20:0,
                 from node/coin.cpp:8:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      node/libbitcoin_server_a-coinstats.o
In file included from ./txmempool.h:20:0,
                 from ./validation.h:21,
                 from node/coinstats.cpp:11:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      node/libbitcoin_server_a-context.o
  CXX      node/libbitcoin_server_a-psbt.o
  CXX      node/libbitcoin_server_a-transaction.o
In file included from ./util/system.h:22:0,
                 from ./addrman.h:15,
                 from ./net.h:10,
                 from node/transaction.cpp:7:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-noui.o
In file included from ./util/system.h:22:0,
                 from noui.cpp:9:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      policy/libbitcoin_server_a-fees.o
In file included from ./txmempool.h:20:0,
                 from policy/fees.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      policy/libbitcoin_server_a-rbf.o
In file included from ./txmempool.h:20:0,
                 from ./policy/rbf.h:8,
                 from policy/rbf.cpp:5:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      policy/libbitcoin_server_a-settings.o
  CXX      libbitcoin_server_a-pow.o
In file included from ./util/system.h:22:0,
                 from ./crypto/verthash.h:12,
                 from pow.cpp:16:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-rest.o
In file included from ./util/system.h:22:0,
                 from ./dbwrapper.h:12,
                 from ./index/base.h:8,
                 from ./index/txindex.h:9,
                 from rest.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      rpc/libbitcoin_server_a-blockchain.o
In file included from ./util/system.h:22:0,
                 from ./dbwrapper.h:12,
                 from ./index/base.h:8,
                 from ./index/blockfilterindex.h:11,
                 from rpc/blockchain.cpp:16:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
rpc/blockchain.cpp:1121:13: warning: ‘void BIP9SoftForkDescPushBack(UniValue&, const string&, const Consensus::Params&, Consensus::DeploymentPos)’ defined but not used [-Wunused-function]
 static void BIP9SoftForkDescPushBack(UniValue& softforks, const std::string &na
             ^
  CXX      rpc/libbitcoin_server_a-mining.o
In file included from ./miner.h:9:0,
                 from rpc/mining.cpp:14:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      rpc/libbitcoin_server_a-misc.o
In file included from ./script/descriptor.h:8:0,
                 from rpc/misc.cpp:14:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      rpc/libbitcoin_server_a-net.o
In file included from ./util/system.h:22:0,
                 from ./addrman.h:15,
                 from ./net.h:10,
                 from rpc/net.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      rpc/libbitcoin_server_a-rawtransaction.o
  CXX      rpc/libbitcoin_server_a-server.o
In file included from ./util/system.h:22:0,
                 from rpc/server.cpp:12:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      script/libbitcoin_server_a-sigcache.o
In file included from ./util/system.h:22:0,
                 from script/sigcache.cpp:11:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-shutdown.o
  CXX      libbitcoin_server_a-timedata.o
In file included from ./util/system.h:22:0,
                 from timedata.cpp:14:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-torcontrol.o
In file included from ./util/system.h:22:0,
                 from ./addrman.h:15,
                 from ./net.h:10,
                 from torcontrol.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-txdb.o
In file included from ./util/system.h:22:0,
                 from ./dbwrapper.h:12,
                 from ./txdb.h:10,
                 from txdb.cpp:6:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-txmempool.o
In file included from ./txmempool.h:20:0,
                 from txmempool.cpp:6:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-ui_interface.o
  CXX      libbitcoin_server_a-validation.o
In file included from ./txmempool.h:20:0,
                 from ./validation.h:21,
                 from validation.cpp:6:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-validationinterface.o
  CXX      libbitcoin_server_a-versionbits.o
  CXX      libbitcoin_server_a-dummywallet.o
In file included from ./util/system.h:22:0,
                 from dummywallet.cpp:5:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  AR       libbitcoin_server.a
  CXX      libbitcoin_common_a-base58.o
  CXX      libbitcoin_common_a-bech32.o
  CXX      libbitcoin_common_a-bloom.o
  CXX      libbitcoin_common_a-chainparams.o
In file included from ./util/system.h:22:0,
                 from chainparams.cpp:11:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_common_a-coins.o
  CXX      libbitcoin_common_a-compressor.o
  CXX      libbitcoin_common_a-core_read.o
  CXX      libbitcoin_common_a-core_write.o
In file included from ./util/system.h:22:0,
                 from core_write.cpp:15:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_common_a-key.o
  CXX      libbitcoin_common_a-key_io.o
  CXX      libbitcoin_common_a-merkleblock.o
  CXX      libbitcoin_common_a-netaddress.o
  CXX      libbitcoin_common_a-netbase.o
In file included from ./util/system.h:22:0,
                 from netbase.cpp:12:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_common_a-net_permissions.o
In file included from ./util/system.h:22:0,
                 from net_permissions.cpp:8:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_common_a-outputtype.o
  CXX      policy/libbitcoin_common_a-feerate.o
  CXX      policy/libbitcoin_common_a-policy.o
  CXX      libbitcoin_common_a-protocol.o
In file included from ./util/system.h:22:0,
                 from protocol.cpp:8:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_common_a-psbt.o
In file included from ./psbt.h:10:0,
                 from psbt.cpp:5:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      rpc/libbitcoin_common_a-rawtransaction_util.o
  CXX      rpc/libbitcoin_common_a-util.o
In file included from ./script/descriptor.h:8:0,
                 from rpc/util.cpp:8:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_common_a-scheduler.o
  CXX      script/libbitcoin_common_a-descriptor.o
  CXX      script/libbitcoin_common_a-sign.o
  CXX      script/libbitcoin_common_a-signingprovider.o
In file included from ./util/system.h:22:0,
                 from script/signingprovider.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      script/libbitcoin_common_a-standard.o
  CXX      libbitcoin_common_a-versionbitsinfo.o
  CXX      libbitcoin_common_a-warnings.o
In file included from ./util/system.h:22:0,
                 from warnings.cpp:9:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  AR       libbitcoin_common.a
make[3]: Entering directory '/home/vertyclank/Downloads/vertcoin-core-0.16.0-rc2/src/univalue'
  CXX      lib/libunivalue_la-univalue.lo
  CXX      lib/libunivalue_la-univalue_get.lo
  CXX      lib/libunivalue_la-univalue_read.lo
  CXX      lib/libunivalue_la-univalue_write.lo
  CXXLD    libunivalue.la
ar: `u' modifier ignored since `D' is the default (see `U')
make[3]: Leaving directory '/home/vertyclank/Downloads/vertcoin-core-0.16.0-rc2/src/univalue'
  CXX      support/libbitcoin_util_a-lockedpool.o
  CXX      libbitcoin_util_a-chainparamsbase.o
In file included from ./util/system.h:22:0,
                 from chainparamsbase.cpp:9:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_util_a-clientversion.o
  CXX      compat/libbitcoin_util_a-glibc_sanity_fdelt.o
  CXX      compat/libbitcoin_util_a-glibc_sanity.o
  CXX      compat/libbitcoin_util_a-glibcxx_sanity.o
  CXX      compat/libbitcoin_util_a-strnlen.o
  CXX      libbitcoin_util_a-fs.o
  CXX      interfaces/libbitcoin_util_a-handler.o
  CXX      libbitcoin_util_a-logging.o
  CXX      libbitcoin_util_a-random.o
  CXX      libbitcoin_util_a-randomenv.o
  CXX      rpc/libbitcoin_util_a-request.o
In file included from ./util/system.h:22:0,
                 from rpc/request.cpp:12:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      support/libbitcoin_util_a-cleanse.o
  CXX      libbitcoin_util_a-sync.o
  CXX      libbitcoin_util_a-threadinterrupt.o
  CXX      util/libbitcoin_util_a-asmap.o
  CXX      util/libbitcoin_util_a-bip32.o
  CXX      util/libbitcoin_util_a-bytevectorhash.o
  CXX      util/libbitcoin_util_a-error.o
In file included from ./util/system.h:22:0,
                 from util/error.cpp:8:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      util/libbitcoin_util_a-fees.o
  CXX      util/libbitcoin_util_a-system.o
  CXX      util/libbitcoin_util_a-message.o
  CXX      util/libbitcoin_util_a-moneystr.o
  CXX      util/libbitcoin_util_a-rbf.o
  CXX      util/libbitcoin_util_a-settings.o
  CXX      util/libbitcoin_util_a-threadnames.o
  CXX      util/libbitcoin_util_a-spanparsing.o
  CXX      util/libbitcoin_util_a-strencodings.o
  CXX      util/libbitcoin_util_a-string.o
  CXX      util/libbitcoin_util_a-time.o
  CXX      util/libbitcoin_util_a-url.o
  AR       libbitcoin_util.a
  CXX      libbitcoin_consensus_a-arith_uint256.o
  CXX      consensus/libbitcoin_consensus_a-merkle.o
  CXX      consensus/libbitcoin_consensus_a-tx_check.o
  CXX      libbitcoin_consensus_a-hash.o
  CXX      primitives/libbitcoin_consensus_a-block.o
In file included from ./util/system.h:22:0,
                 from ./crypto/verthash.h:12,
                 from primitives/block.cpp:13:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      primitives/libbitcoin_consensus_a-transaction.o
  CXX      libbitcoin_consensus_a-pubkey.o
  CXX      script/libbitcoin_consensus_a-bitcoinconsensus.o
  CXX      script/libbitcoin_consensus_a-interpreter.o
  CXX      script/libbitcoin_consensus_a-script.o
  CXX      script/libbitcoin_consensus_a-script_error.o
  CXX      libbitcoin_consensus_a-uint256.o
  CXX      util/libbitcoin_consensus_a-strencodings.o
  AR       libbitcoin_consensus.a
  CXX      crypto/crypto_libbitcoin_crypto_base_a-aes.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-chacha_poly_aead.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-chacha20.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-hkdf_sha256_32.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-hmac_sha256.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-hmac_sha512.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-poly1305.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-ripemd160.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-sha1.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-sha256.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-sha512.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-scrypt.o
crypto/scrypt.cpp: In function ‘void scrypt_N_1_1_256(const char*, char*, unsigned char)’:
crypto/scrypt.cpp:248:52: warning: variable length array ‘scratchpad’ is used [-Wvla]
  char scratchpad[((1 << (Nfactor + 1)) * 128 ) + 63];
                                                    ^
crypto/scrypt.cpp:246:6: warning: stack protector not protecting local variables: variable length buffer [-Wstack-protector]
 void scrypt_N_1_1_256(const char *input, char *output, unsigned char Nfactor)
      ^
In file included from ./util/system.h:22:0,
                 from crypto/scrypt.cpp:34:
./optional.h: At global scope:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      crypto/crypto_libbitcoin_crypto_base_a-scrypt-sse2.o
  CC       crypto/Lyra2RE/crypto_libbitcoin_crypto_base_a-Lyra2RE.o
  CC       crypto/Lyra2RE/crypto_libbitcoin_crypto_base_a-Lyra2.o
  CC       crypto/Lyra2RE/crypto_libbitcoin_crypto_base_a-Sponge.o
  CC       crypto/Lyra2RE/crypto_libbitcoin_crypto_base_a-blake.o
  CC       crypto/Lyra2RE/crypto_libbitcoin_crypto_base_a-groestl.o
  CC       crypto/Lyra2RE/crypto_libbitcoin_crypto_base_a-keccak.o
  CC       crypto/Lyra2RE/crypto_libbitcoin_crypto_base_a-skein.o
  CC       crypto/Lyra2RE/crypto_libbitcoin_crypto_base_a-cubehash.o
  CC       crypto/Lyra2RE/crypto_libbitcoin_crypto_base_a-bmw.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-siphash.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-verthash_datfile.o
In file included from ./util/system.h:22:0,
                 from ./crypto/verthash_datfile.h:13,
                 from crypto/verthash_datfile.cpp:1:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CC       crypto/tiny_sha3/crypto_libbitcoin_crypto_base_a-sha3.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-verthash.o
crypto/verthash.cpp: In static member function ‘static void Verthash::Hash(const char*, char*)’:
crypto/verthash.cpp:128:68: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result]
                 fread(&value, sizeof(uint32_t), 1, VerthashDatFile);
                                                                    ^
crypto/verthash.cpp:150:32: warning: ‘VerthashDatFile’ may be used uninitialized in this function [-Wmaybe-uninitialized]
         fclose(VerthashDatFile);
                                ^
In file included from ./util/system.h:22:0,
                 from ./crypto/verthash.h:12,
                 from crypto/verthash.cpp:1:
./optional.h: At global scope:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      crypto/crypto_libbitcoin_crypto_base_a-sha256_sse4.o
  AR       crypto/libbitcoin_crypto_base.a
  CXX      crypto/crypto_libbitcoin_crypto_sse41_a-sha256_sse41.o
  AR       crypto/libbitcoin_crypto_sse41.a
  CXX      crypto/crypto_libbitcoin_crypto_avx2_a-sha256_avx2.o
  AR       crypto/libbitcoin_crypto_avx2.a
  CXX      crypto/crypto_libbitcoin_crypto_shani_a-sha256_shani.o
  AR       crypto/libbitcoin_crypto_shani.a
  CXX      leveldb/db/leveldb_libleveldb_a-builder.o
  CXX      leveldb/db/leveldb_libleveldb_a-c.o
  CXX      leveldb/db/leveldb_libleveldb_a-dbformat.o
  CXX      leveldb/db/leveldb_libleveldb_a-db_impl.o
  CXX      leveldb/db/leveldb_libleveldb_a-db_iter.o
  CXX      leveldb/db/leveldb_libleveldb_a-dumpfile.o
  CXX      leveldb/db/leveldb_libleveldb_a-filename.o
  CXX      leveldb/db/leveldb_libleveldb_a-log_reader.o
  CXX      leveldb/db/leveldb_libleveldb_a-log_writer.o
  CXX      leveldb/db/leveldb_libleveldb_a-memtable.o
  CXX      leveldb/db/leveldb_libleveldb_a-repair.o
  CXX      leveldb/db/leveldb_libleveldb_a-table_cache.o
  CXX      leveldb/db/leveldb_libleveldb_a-version_edit.o
  CXX      leveldb/db/leveldb_libleveldb_a-version_set.o
  CXX      leveldb/db/leveldb_libleveldb_a-write_batch.o
  CXX      leveldb/table/leveldb_libleveldb_a-block_builder.o
  CXX      leveldb/table/leveldb_libleveldb_a-block.o
  CXX      leveldb/table/leveldb_libleveldb_a-filter_block.o
  CXX      leveldb/table/leveldb_libleveldb_a-format.o
  CXX      leveldb/table/leveldb_libleveldb_a-iterator.o
  CXX      leveldb/table/leveldb_libleveldb_a-merger.o
  CXX      leveldb/table/leveldb_libleveldb_a-table_builder.o
  CXX      leveldb/table/leveldb_libleveldb_a-table.o
  CXX      leveldb/table/leveldb_libleveldb_a-two_level_iterator.o
  CXX      leveldb/util/leveldb_libleveldb_a-arena.o
  CXX      leveldb/util/leveldb_libleveldb_a-bloom.o
  CXX      leveldb/util/leveldb_libleveldb_a-cache.o
  CXX      leveldb/util/leveldb_libleveldb_a-coding.o
  CXX      leveldb/util/leveldb_libleveldb_a-comparator.o
  CXX      leveldb/util/leveldb_libleveldb_a-crc32c.o
  CXX      leveldb/util/leveldb_libleveldb_a-env.o
  CXX      leveldb/util/leveldb_libleveldb_a-filter_policy.o
  CXX      leveldb/util/leveldb_libleveldb_a-hash.o
  CXX      leveldb/util/leveldb_libleveldb_a-histogram.o
  CXX      leveldb/util/leveldb_libleveldb_a-logging.o
  CXX      leveldb/util/leveldb_libleveldb_a-options.o
  CXX      leveldb/util/leveldb_libleveldb_a-status.o
  CXX      leveldb/util/leveldb_libleveldb_a-env_posix.o
  AR       leveldb/libleveldb.a
  CXX      crc32c/src/crc32c_libcrc32c_a-crc32c.o
  CXX      crc32c/src/crc32c_libcrc32c_a-crc32c_portable.o
  AR       crc32c/libcrc32c.a
  CXX      crc32c/src/crc32c_libcrc32c_sse42_a-crc32c_sse42.o
  AR       crc32c/libcrc32c_sse42.a
  CXX      leveldb/helpers/memenv/leveldb_libmemenv_a-memenv.o
  AR       leveldb/libmemenv.a
  CXXLD    vertcoind
/usr/bin/ld: vertcoind-bitcoind.o: undefined reference to symbol '_ZN5boost6system15system_categoryEv'
//usr/lib/x86_64-linux-gnu/libboost_system.so.1.58.0: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
Makefile:7907: recipe for target 'vertcoind' failed
make[2]: *** [vertcoind] Error 1
make[2]: Leaving directory '/home/vertyclank/Downloads/vertcoin-core-0.16.0-rc2/src'
Makefile:17240: recipe for target 'all-recursive' failed
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory '/home/vertyclank/Downloads/vertcoin-core-0.16.0-rc2/src'
Makefile:781: recipe for target 'all-recursive' failed
make: *** [all-recursive] Error 1

============================================================ This portion is to show the output of the same compile procedure, but for bitcoin-0.20.1

vertyclank@buildvm:~/Downloads/bitcoin-0.20.1$ ./autogen.sh

libtoolize: copying file 'build-aux/ltmain.sh'
libtoolize: putting macros in AC_CONFIG_MACRO_DIRS, 'build-aux/m4'.
libtoolize: copying file 'build-aux/m4/libtool.m4'
libtoolize: copying file 'build-aux/m4/ltoptions.m4'
libtoolize: copying file 'build-aux/m4/ltsugar.m4'
libtoolize: copying file 'build-aux/m4/ltversion.m4'
libtoolize: copying file 'build-aux/m4/lt~obsolete.m4'
configure.ac:45: installing 'build-aux/compile'
configure.ac:45: installing 'build-aux/config.guess'
configure.ac:45: installing 'build-aux/config.sub'
configure.ac:28: installing 'build-aux/install-sh'
configure.ac:28: installing 'build-aux/missing'
Makefile.am: installing 'build-aux/depcomp'
parallel-tests: installing 'build-aux/test-driver'
libtoolize: putting auxiliary files in AC_CONFIG_AUX_DIR, 'build-aux'.
libtoolize: copying file 'build-aux/ltmain.sh'
libtoolize: putting macros in AC_CONFIG_MACRO_DIRS, 'build-aux/m4'.
libtoolize: copying file 'build-aux/m4/libtool.m4'
libtoolize: copying file 'build-aux/m4/ltoptions.m4'
libtoolize: copying file 'build-aux/m4/ltsugar.m4'
libtoolize: copying file 'build-aux/m4/ltversion.m4'
libtoolize: copying file 'build-aux/m4/lt~obsolete.m4'
configure.ac:10: installing 'build-aux/compile'
configure.ac:5: installing 'build-aux/config.guess'
configure.ac:5: installing 'build-aux/config.sub'
configure.ac:9: installing 'build-aux/install-sh'
configure.ac:9: installing 'build-aux/missing'
Makefile.am: installing 'build-aux/depcomp'
parallel-tests: installing 'build-aux/test-driver'
libtoolize: putting auxiliary files in AC_CONFIG_AUX_DIR, 'build-aux'.
libtoolize: copying file 'build-aux/ltmain.sh'
libtoolize: putting macros in AC_CONFIG_MACRO_DIRS, 'build-aux/m4'.
libtoolize: copying file 'build-aux/m4/libtool.m4'
libtoolize: copying file 'build-aux/m4/ltoptions.m4'
libtoolize: copying file 'build-aux/m4/ltsugar.m4'
libtoolize: copying file 'build-aux/m4/ltversion.m4'
libtoolize: copying file 'build-aux/m4/lt~obsolete.m4'
configure.ac:83: installing 'build-aux/compile'
configure.ac:29: installing 'build-aux/config.guess'
configure.ac:29: installing 'build-aux/config.sub'
configure.ac:39: installing 'build-aux/install-sh'
configure.ac:39: installing 'build-aux/missing'
src/Makefile.am: installing 'build-aux/depcomp'
parallel-tests: installing 'build-aux/test-driver'

vertyclank@buildvm:~/Downloads/bitcoin-0.20.1$ ./configure --prefix=$PWD/depends/aarch64-linux-gnu --disable-wallet --without-gui --without-miniupnpc

checking host system type... x86_64-pc-linux-gnu
checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /bin/mkdir -p
checking for gawk... no
checking for mawk... mawk
checking whether make sets $(MAKE)... yes
checking whether make supports nested variables... yes
checking whether to enable maintainer-specific portions of Makefiles... yes
checking whether make supports nested variables... (cached) yes
checking for g++... g++
checking whether the C++ compiler works... yes
checking for C++ compiler default output file name... a.out
checking for suffix of executables... 
checking whether we are cross compiling... no
checking for suffix of object files... o
checking whether we are using the GNU C++ compiler... yes
checking whether g++ accepts -g... yes
checking for style of include used by make... GNU
checking dependency style of g++... gcc3
checking whether g++ supports C++11 features with -std=c++11... yes
checking whether std::atomic can be used without link library... yes
checking whether we are using the GNU Objective C++ compiler... no
checking whether g++ -std=c++11 accepts -g... no
checking dependency style of g++ -std=c++11... gcc3
checking how to print strings... printf
checking for gcc... gcc
checking whether we are using the GNU C compiler... yes
checking whether gcc accepts -g... yes
checking for gcc option to accept ISO C89... none needed
checking whether gcc understands -c and -o together... yes
checking dependency style of gcc... gcc3
checking for a sed that does not truncate output... /bin/sed
checking for grep that handles long lines and -e... /bin/grep
checking for egrep... /bin/grep -E
checking for fgrep... /bin/grep -F
checking for ld used by gcc... /usr/bin/ld
checking if the linker (/usr/bin/ld) is GNU ld... yes
checking for BSD- or MS-compatible name lister (nm)... /usr/bin/nm -B
checking the name lister (/usr/bin/nm -B) interface... BSD nm
checking whether ln -s works... yes
checking the maximum length of command line arguments... 1572864
checking how to convert x86_64-pc-linux-gnu file names to x86_64-pc-linux-gnu format... func_convert_file_noop
checking how to convert x86_64-pc-linux-gnu file names to toolchain format... func_convert_file_noop
checking for /usr/bin/ld option to reload object files... -r
checking for objdump... objdump
checking how to recognize dependent libraries... pass_all
checking for dlltool... no
checking how to associate runtime and link libraries... printf %s\n
checking for ar... ar
checking for archiver @FILE support... @
checking for strip... strip
checking for ranlib... ranlib
checking command to parse /usr/bin/nm -B output from gcc object... ok
checking for sysroot... no
checking for a working dd... /bin/dd
checking how to truncate binary pipes... /bin/dd bs=4096 count=1
checking for mt... mt
checking if mt is a manifest tool... no
checking how to run the C preprocessor... gcc -E
checking for ANSI C header files... yes
checking for sys/types.h... yes
checking for sys/stat.h... yes
checking for stdlib.h... yes
checking for string.h... yes
checking for memory.h... yes
checking for strings.h... yes
checking for inttypes.h... yes
checking for stdint.h... yes
checking for unistd.h... yes
checking for dlfcn.h... yes
checking for objdir... .libs
checking if gcc supports -fno-rtti -fno-exceptions... no
checking for gcc option to produce PIC... -fPIC -DPIC
checking if gcc PIC flag -fPIC -DPIC works... yes
checking if gcc static flag -static works... yes
checking if gcc supports -c -o file.o... yes
checking if gcc supports -c -o file.o... (cached) yes
checking whether the gcc linker (/usr/bin/ld -m elf_x86_64) supports shared libraries... yes
checking whether -lc should be explicitly linked in... no
checking dynamic linker characteristics... GNU/Linux ld.so
checking how to hardcode library paths into programs... immediate
checking whether stripping libraries is possible... yes
checking if libtool supports shared libraries... yes
checking whether to build shared libraries... yes
checking whether to build static libraries... yes
checking how to run the C++ preprocessor... g++ -std=c++11 -E
checking for ld used by g++ -std=c++11... /usr/bin/ld -m elf_x86_64
checking if the linker (/usr/bin/ld -m elf_x86_64) is GNU ld... yes
checking whether the g++ -std=c++11 linker (/usr/bin/ld -m elf_x86_64) supports shared libraries... yes
checking for g++ -std=c++11 option to produce PIC... -fPIC -DPIC
checking if g++ -std=c++11 PIC flag -fPIC -DPIC works... yes
checking if g++ -std=c++11 static flag -static works... yes
checking if g++ -std=c++11 supports -c -o file.o... yes
checking if g++ -std=c++11 supports -c -o file.o... (cached) yes
checking whether the g++ -std=c++11 linker (/usr/bin/ld -m elf_x86_64) supports shared libraries... yes
checking dynamic linker characteristics... (cached) GNU/Linux ld.so
checking how to hardcode library paths into programs... immediate
checking for ar... /usr/bin/ar
checking for ranlib... /usr/bin/ranlib
checking for strip... /usr/bin/strip
checking for gcov... /usr/bin/gcov
checking for lcov... no
checking for python3.5... /usr/bin/python3.5
checking for genhtml... no
checking for git... no
checking for ccache... no
checking for xgettext... /usr/bin/xgettext
checking for hexdump... /usr/bin/hexdump
checking for readelf... /usr/bin/readelf
checking for c++filt... /usr/bin/c++filt
checking for objcopy... /usr/bin/objcopy
checking for doxygen... no
configure: WARNING: Doxygen not found
checking whether C++ compiler accepts -Werror... yes
checking whether C++ compiler accepts -Wall... yes
checking whether C++ compiler accepts -Wextra... yes
checking whether C++ compiler accepts -Wformat... yes
checking whether C++ compiler accepts -Wvla... yes
checking whether C++ compiler accepts -Wswitch... yes
checking whether C++ compiler accepts -Wformat-security... yes
checking whether C++ compiler accepts -Wthread-safety-analysis... no
checking whether C++ compiler accepts -Wrange-loop-analysis... no
checking whether C++ compiler accepts -Wredundant-decls... yes
checking whether C++ compiler accepts -Wunused-variable... yes
checking whether C++ compiler accepts -Wdate-time... yes
checking whether C++ compiler accepts -Wunused-parameter... yes
checking whether C++ compiler accepts -Wself-assign... no
checking whether C++ compiler accepts -Wunused-local-typedef... no
checking whether C++ compiler accepts -Wdeprecated-register... no
checking whether C++ compiler accepts -Wimplicit-fallthrough... no
checking whether C++ compiler accepts -msse4.2... yes
checking whether C++ compiler accepts -msse4.1... yes
checking whether C++ compiler accepts -mavx -mavx2... yes
checking whether C++ compiler accepts -msse4 -msha... yes
checking for SSE4.2 intrinsics... yes
checking for SSE4.1 intrinsics... yes
checking for AVX2 intrinsics... yes
checking for SHA-NI intrinsics... yes
checking whether C++ compiler accepts -march=armv8-a+crc+crypto... no
checking for ARM CRC32 intrinsics... no
checking for pkg-config... /usr/bin/pkg-config
checking pkg-config is at least version 0.9.0... yes
checking whether byte ordering is bigendian... no
checking whether gcc is Clang... no
checking whether pthreads work with -pthread... yes
checking for joinable pthread attribute... PTHREAD_CREATE_JOINABLE
checking whether more special flags are required for pthreads... no
checking for PTHREAD_PRIO_INHERIT... yes
checking for special C compiler options needed for large files... no
checking for _FILE_OFFSET_BITS value needed for large files... no
checking whether strerror_r is declared... yes
checking for strerror_r... yes
checking whether strerror_r returns char *... yes
checking for __attribute__((visibility))... yes
checking for __attribute__((dllexport))... no
checking for __attribute__((dllimport))... no
checking for library containing clock_gettime... none required
checking whether C++ compiler accepts -fPIC... yes
checking whether C++ compiler accepts -fstack-reuse=none... yes
checking whether C++ compiler accepts -Wstack-protector... yes
checking whether C++ compiler accepts -fstack-protector-all... yes
checking whether C++ preprocessor accepts -D_FORTIFY_SOURCE=2... yes
checking whether C++ preprocessor accepts -U_FORTIFY_SOURCE... yes
checking whether the linker accepts -Wl,--dynamicbase... no
checking whether the linker accepts -Wl,--nxcompat... no
checking whether the linker accepts -Wl,--high-entropy-va... no
checking whether the linker accepts -Wl,-z,relro... yes
checking whether the linker accepts -Wl,-z,now... yes
checking whether the linker accepts -fPIE -pie... yes
checking endian.h usability... yes
checking endian.h presence... yes
checking for endian.h... yes
checking sys/endian.h usability... no
checking sys/endian.h presence... no
checking for sys/endian.h... no
checking byteswap.h usability... yes
checking byteswap.h presence... yes
checking for byteswap.h... yes
checking stdio.h usability... yes
checking stdio.h presence... yes
checking for stdio.h... yes
checking for stdlib.h... (cached) yes
checking for unistd.h... (cached) yes
checking for strings.h... (cached) yes
checking for sys/types.h... (cached) yes
checking for sys/stat.h... (cached) yes
checking sys/select.h usability... yes
checking sys/select.h presence... yes
checking for sys/select.h... yes
checking sys/prctl.h usability... yes
checking sys/prctl.h presence... yes
checking for sys/prctl.h... yes
checking sys/sysctl.h usability... yes
checking sys/sysctl.h presence... yes
checking for sys/sysctl.h... yes
checking vm/vm_param.h usability... no
checking vm/vm_param.h presence... no
checking for vm/vm_param.h... no
checking sys/vmmeter.h usability... no
checking sys/vmmeter.h presence... no
checking for sys/vmmeter.h... no
checking sys/resources.h usability... no
checking sys/resources.h presence... no
checking for sys/resources.h... no
checking FD_ZERO memcpy dependence... no
checking whether getifaddrs is declared... yes
checking whether freeifaddrs is declared... yes
checking whether strnlen is declared... yes
checking whether daemon is declared... yes
checking whether le16toh is declared... yes
checking whether le32toh is declared... yes
checking whether le64toh is declared... yes
checking whether htole16 is declared... yes
checking whether htole32 is declared... yes
checking whether htole64 is declared... yes
checking whether be16toh is declared... yes
checking whether be32toh is declared... yes
checking whether be64toh is declared... yes
checking whether htobe16 is declared... yes
checking whether htobe32 is declared... yes
checking whether htobe64 is declared... yes
checking whether bswap_16 is declared... yes
checking whether bswap_32 is declared... yes
checking whether bswap_64 is declared... yes
checking whether __builtin_clz is declared... yes
checking whether __builtin_clzl is declared... yes
checking whether __builtin_clzll is declared... yes
checking for getmemoryinfo... yes
checking for mallopt M_ARENA_MAX... yes
checking for visibility attribute... yes
checking for thread_local support... yes
checking for gmtime_r... yes
checking for Linux getrandom syscall... yes
checking for getentropy... no
checking for getentropy via random.h... no
checking for sysctl... no
checking for sysctl KERN_ARND... no
checking for if type char equals int8_t... no
checking for fdatasync... yes
checking for F_FULLFSYNC... no
checking for O_CLOEXEC... yes
checking for __builtin_prefetch... yes
checking for _mm_prefetch... yes
checking for strong getauxval support in the system headers... no
checking for weak getauxval support in the compiler... yes
checking for std::system... yes
checking for ::_wsystem... no
checking whether to build Bitcoin Core GUI... no
checking for boostlib >= 1.47.0 (104700)... yes
checking whether the Boost::System library is available... yes
checking for exit in -lboost_system... yes
checking whether the Boost::Filesystem library is available... yes
checking for exit in -lboost_filesystem... yes
checking whether the Boost::Thread library is available... yes
checking for exit in -lboost_thread... yes
checking whether the Boost::Unit_Test_Framework library is available... yes
checking for dynamic linked boost test... yes
checking for mismatched boost c++11 scoped enums... ok
checking for EVENT... yes
checking for EVENT_PTHREADS... yes
checking for ZMQ... no
configure: WARNING: libzmq version 4.x or greater not found, disabling
checking whether to build bitcoind... yes
checking whether to build bitcoin-cli... yes
checking whether to build bitcoin-tx... yes
checking whether to build bitcoin-wallet... yes
checking whether to build libraries... yes
checking if ccache should be used... no
checking if wallet should be enabled... no
checking whether to build with support for UPnP... no
checking whether to build test_bitcoin... yes
checking whether to reduce exports... no
checking that generated files are newer than configure... done
configure: creating ./config.status
config.status: creating libbitcoinconsensus.pc
config.status: creating Makefile
config.status: creating src/Makefile
config.status: creating doc/man/Makefile
config.status: creating share/setup.nsi
config.status: creating share/qt/Info.plist
config.status: creating test/config.ini
config.status: creating contrib/devtools/split-debug.sh
config.status: creating src/config/bitcoin-config.h
config.status: executing depfiles commands
config.status: executing libtool commands
=== configuring in src/univalue (/home/vertyclank/Downloads/bitcoin-0.20.1/src/univalue)
configure: running /bin/bash ./configure --disable-option-checking '--prefix=/home/vertyclank/Downloads/bitcoin-0.20.1/depends/aarch64-linux-gnu'  '--disable-wallet' '--without-gui' '--without-miniupnpc' '--disable-shared' '--with-pic' '--enable-benchmark=no' '--with-bignum=no' '--enable-module-recovery' '--disable-jni' --cache-file=/dev/null --srcdir=.
checking whether make supports nested variables... yes
checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /bin/mkdir -p
checking for gawk... no
checking for mawk... mawk
checking whether make sets $(MAKE)... yes
checking build system type... x86_64-pc-linux-gnu
checking host system type... x86_64-pc-linux-gnu
checking how to print strings... printf
checking for style of include used by make... GNU
checking for gcc... gcc
checking whether the C compiler works... yes
checking for C compiler default output file name... a.out
checking for suffix of executables... 
checking whether we are cross compiling... no
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether gcc accepts -g... yes
checking for gcc option to accept ISO C89... none needed
checking whether gcc understands -c and -o together... yes
checking dependency style of gcc... gcc3
checking for a sed that does not truncate output... /bin/sed
checking for grep that handles long lines and -e... /bin/grep
checking for egrep... /bin/grep -E
checking for fgrep... /bin/grep -F
checking for ld used by gcc... /usr/bin/ld
checking if the linker (/usr/bin/ld) is GNU ld... yes
checking for BSD- or MS-compatible name lister (nm)... /usr/bin/nm -B
checking the name lister (/usr/bin/nm -B) interface... BSD nm
checking whether ln -s works... yes
checking the maximum length of command line arguments... 1572864
checking how to convert x86_64-pc-linux-gnu file names to x86_64-pc-linux-gnu format... func_convert_file_noop
checking how to convert x86_64-pc-linux-gnu file names to toolchain format... func_convert_file_noop
checking for /usr/bin/ld option to reload object files... -r
checking for objdump... objdump
checking how to recognize dependent libraries... pass_all
checking for dlltool... no
checking how to associate runtime and link libraries... printf %s\n
checking for ar... ar
checking for archiver @FILE support... @
checking for strip... strip
checking for ranlib... ranlib
checking command to parse /usr/bin/nm -B output from gcc object... ok
checking for sysroot... no
checking for a working dd... /bin/dd
checking how to truncate binary pipes... /bin/dd bs=4096 count=1
checking for mt... mt
checking if mt is a manifest tool... no
checking how to run the C preprocessor... gcc -E
checking for ANSI C header files... yes
checking for sys/types.h... yes
checking for sys/stat.h... yes
checking for stdlib.h... yes
checking for string.h... yes
checking for memory.h... yes
checking for strings.h... yes
checking for inttypes.h... yes
checking for stdint.h... yes
checking for unistd.h... yes
checking for dlfcn.h... yes
checking for objdir... .libs
checking if gcc supports -fno-rtti -fno-exceptions... no
checking for gcc option to produce PIC... -fPIC -DPIC
checking if gcc PIC flag -fPIC -DPIC works... yes
checking if gcc static flag -static works... yes
checking if gcc supports -c -o file.o... yes
checking if gcc supports -c -o file.o... (cached) yes
checking whether the gcc linker (/usr/bin/ld -m elf_x86_64) supports shared libraries... yes
checking dynamic linker characteristics... GNU/Linux ld.so
checking how to hardcode library paths into programs... immediate
checking whether stripping libraries is possible... yes
checking if libtool supports shared libraries... yes
checking whether to build shared libraries... no
checking whether to build static libraries... yes
checking for g++... g++
checking whether we are using the GNU C++ compiler... yes
checking whether g++ accepts -g... yes
checking dependency style of g++... gcc3
checking how to run the C++ preprocessor... g++ -E
checking for ld used by g++... /usr/bin/ld -m elf_x86_64
checking if the linker (/usr/bin/ld -m elf_x86_64) is GNU ld... yes
checking whether the g++ linker (/usr/bin/ld -m elf_x86_64) supports shared libraries... yes
checking for g++ option to produce PIC... -fPIC -DPIC
checking if g++ PIC flag -fPIC -DPIC works... yes
checking if g++ static flag -static works... yes
checking if g++ supports -c -o file.o... yes
checking if g++ supports -c -o file.o... (cached) yes
checking whether the g++ linker (/usr/bin/ld -m elf_x86_64) supports shared libraries... yes
checking dynamic linker characteristics... (cached) GNU/Linux ld.so
checking how to hardcode library paths into programs... immediate
checking that generated files are newer than configure... done
configure: creating ./config.status
config.status: creating Makefile
config.status: creating pc/libunivalue.pc
config.status: creating pc/libunivalue-uninstalled.pc
config.status: creating univalue-config.h
config.status: executing depfiles commands
config.status: executing libtool commands
=== configuring in src/secp256k1 (/home/vertyclank/Downloads/bitcoin-0.20.1/src/secp256k1)
configure: running /bin/bash ./configure --disable-option-checking '--prefix=/home/vertyclank/Downloads/bitcoin-0.20.1/depends/aarch64-linux-gnu'  '--disable-wallet' '--without-gui' '--without-miniupnpc' '--disable-shared' '--with-pic' '--enable-benchmark=no' '--with-bignum=no' '--enable-module-recovery' '--disable-jni' --cache-file=/dev/null --srcdir=.
checking build system type... x86_64-pc-linux-gnu
checking host system type... x86_64-pc-linux-gnu
checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /bin/mkdir -p
checking for gawk... no
checking for mawk... mawk
checking whether make sets $(MAKE)... yes
checking whether make supports nested variables... yes
checking how to print strings... printf
checking for style of include used by make... GNU
checking for gcc... gcc
checking whether the C compiler works... yes
checking for C compiler default output file name... a.out
checking for suffix of executables... 
checking whether we are cross compiling... no
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether gcc accepts -g... yes
checking for gcc option to accept ISO C89... none needed
checking whether gcc understands -c and -o together... yes
checking dependency style of gcc... gcc3
checking for a sed that does not truncate output... /bin/sed
checking for grep that handles long lines and -e... /bin/grep
checking for egrep... /bin/grep -E
checking for fgrep... /bin/grep -F
checking for ld used by gcc... /usr/bin/ld
checking if the linker (/usr/bin/ld) is GNU ld... yes
checking for BSD- or MS-compatible name lister (nm)... /usr/bin/nm -B
checking the name lister (/usr/bin/nm -B) interface... BSD nm
checking whether ln -s works... yes
checking the maximum length of command line arguments... 1572864
checking how to convert x86_64-pc-linux-gnu file names to x86_64-pc-linux-gnu format... func_convert_file_noop
checking how to convert x86_64-pc-linux-gnu file names to toolchain format... func_convert_file_noop
checking for /usr/bin/ld option to reload object files... -r
checking for objdump... objdump
checking how to recognize dependent libraries... pass_all
checking for dlltool... no
checking how to associate runtime and link libraries... printf %s\n
checking for ar... ar
checking for archiver @FILE support... @
checking for strip... strip
checking for ranlib... ranlib
checking command to parse /usr/bin/nm -B output from gcc object... ok
checking for sysroot... no
checking for a working dd... /bin/dd
checking how to truncate binary pipes... /bin/dd bs=4096 count=1
checking for mt... mt
checking if mt is a manifest tool... no
checking how to run the C preprocessor... gcc -E
checking for ANSI C header files... yes
checking for sys/types.h... yes
checking for sys/stat.h... yes
checking for stdlib.h... yes
checking for string.h... yes
checking for memory.h... yes
checking for strings.h... yes
checking for inttypes.h... yes
checking for stdint.h... yes
checking for unistd.h... yes
checking for dlfcn.h... yes
checking for objdir... .libs
checking if gcc supports -fno-rtti -fno-exceptions... no
checking for gcc option to produce PIC... -fPIC -DPIC
checking if gcc PIC flag -fPIC -DPIC works... yes
checking if gcc static flag -static works... yes
checking if gcc supports -c -o file.o... yes
checking if gcc supports -c -o file.o... (cached) yes
checking whether the gcc linker (/usr/bin/ld -m elf_x86_64) supports shared libraries... yes
checking dynamic linker characteristics... GNU/Linux ld.so
checking how to hardcode library paths into programs... immediate
checking whether stripping libraries is possible... yes
checking if libtool supports shared libraries... yes
checking whether to build shared libraries... no
checking whether to build static libraries... yes
checking whether make supports nested variables... (cached) yes
checking for pkg-config... /usr/bin/pkg-config
checking pkg-config is at least version 0.9.0... yes
checking for ar... /usr/bin/ar
checking for ranlib... /usr/bin/ranlib
checking for strip... /usr/bin/strip
checking for gcc... gcc
checking whether we are using the GNU C compiler... (cached) yes
checking whether gcc accepts -g... yes
checking for gcc option to accept ISO C89... (cached) none needed
checking whether gcc understands -c and -o together... (cached) yes
checking dependency style of gcc... (cached) gcc3
checking how to run the C preprocessor... gcc -E
checking for gcc option to accept ISO C89... (cached) none needed
checking dependency style of gcc... gcc3
checking if gcc supports -std=c89 -pedantic -Wall -Wextra -Wcast-align -Wnested-externs -Wshadow -Wstrict-prototypes -Wno-unused-function -Wno-long-long -Wno-overlength-strings... yes
checking if gcc supports -fvisibility=hidden... yes
checking for __int128... yes
checking if native gcc supports -Wall -Wextra -Wno-unused-function... yes
checking for working native compiler: gcc... yes
checking for x86_64 assembly availability... yes
checking for CRYPTO... no
checking openssl/crypto.h usability... no
checking openssl/crypto.h presence... no
checking for openssl/crypto.h... no
checking whether byte ordering is bigendian... no
checking that generated files are newer than configure... done
configure: creating ./config.status
config.status: creating Makefile
config.status: creating libsecp256k1.pc
config.status: creating src/libsecp256k1-config.h
config.status: executing depfiles commands
config.status: executing libtool commands

Build Options:
  with endomorphism   = no
  with ecmult precomp = yes
  with jni            = no
  with benchmarks     = no
  with coverage       = no
  module ecdh         = no
  module recovery     = yes

  asm                 = x86_64
  bignum              = no
  field               = 64bit
  scalar              = 64bit

  CC                  = gcc
  CFLAGS              = -g -O2 -W -std=c89 -pedantic -Wall -Wextra -Wcast-align -Wnested-externs -Wshadow -Wstrict-prototypes -Wno-unused-function -Wno-long-long -Wno-overlength-strings -fvisibility=hidden -O3
  CPPFLAGS            = 
  LDFLAGS             = 

Options used to compile and link:
  with wallet   = no
  with gui / qt = no
  with zmq      = no
  with test     = yes
    with fuzz   = no
  with bench    = yes
  with upnp     = no
  use asm       = yes
  sanitizers    = 
  debug enabled = no
  gprof enabled = no
  werror        = no

  target os     = linux
  build os      = linux-gnu

  CC            = gcc
  CFLAGS        = -g -O2
  CPPFLAGS      =   -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2  -DHAVE_BUILD_INFO -D__STDC_FORMAT_MACROS
  CXX           = g++ -std=c++11
  CXXFLAGS      =   -fstack-reuse=none -Wstack-protector -fstack-protector-all  -Wall -Wextra -Wformat -Wvla -Wswitch -Wformat-security -Wredundant-decls -Wunused-variable -Wdate-time  -Wno-unused-parameter   -g -O2
  LDFLAGS       = -pthread  -Wl,-z,relro -Wl,-z,now -pie  
  ARFLAGS       = cr```

vertyclank@buildvm:~/Downloads/bitcoin-0.20.1$ make HOST=aarch64-linux-gnu
```Making all in src
make[1]: Entering directory '/home/vertyclank/Downloads/bitcoin-0.20.1/src'
make[2]: Entering directory '/home/vertyclank/Downloads/bitcoin-0.20.1/src'
  CXX      support/libbitcoinconsensus_la-cleanse.lo
  CXX      crypto/libbitcoinconsensus_la-aes.lo
  CXX      crypto/libbitcoinconsensus_la-chacha_poly_aead.lo
  CXX      crypto/libbitcoinconsensus_la-chacha20.lo
  CXX      crypto/libbitcoinconsensus_la-hkdf_sha256_32.lo
  CXX      crypto/libbitcoinconsensus_la-hmac_sha256.lo
  CXX      crypto/libbitcoinconsensus_la-hmac_sha512.lo
  CXX      crypto/libbitcoinconsensus_la-poly1305.lo
  CXX      crypto/libbitcoinconsensus_la-ripemd160.lo
  CXX      crypto/libbitcoinconsensus_la-sha1.lo
  CXX      crypto/libbitcoinconsensus_la-sha256.lo
  CXX      crypto/libbitcoinconsensus_la-sha512.lo
  CXX      crypto/libbitcoinconsensus_la-siphash.lo
  CXX      crypto/libbitcoinconsensus_la-sha256_sse4.lo
  CXX      libbitcoinconsensus_la-arith_uint256.lo
  CXX      consensus/libbitcoinconsensus_la-merkle.lo
  CXX      consensus/libbitcoinconsensus_la-tx_check.lo
  CXX      libbitcoinconsensus_la-hash.lo
  CXX      primitives/libbitcoinconsensus_la-block.lo
  CXX      primitives/libbitcoinconsensus_la-transaction.lo
  CXX      libbitcoinconsensus_la-pubkey.lo
  CXX      script/libbitcoinconsensus_la-bitcoinconsensus.lo
  CXX      script/libbitcoinconsensus_la-interpreter.lo
  CXX      script/libbitcoinconsensus_la-script.lo
  CXX      script/libbitcoinconsensus_la-script_error.lo
  CXX      libbitcoinconsensus_la-uint256.lo
  CXX      util/libbitcoinconsensus_la-strencodings.lo
make[3]: Entering directory '/home/vertyclank/Downloads/bitcoin-0.20.1/src/secp256k1'
gcc -I. -g -O2 -Wall -Wextra -Wno-unused-function -c src/gen_context.c -o gen_context.o
gcc -g -O2 -Wall -Wextra -Wno-unused-function  gen_context.o -o gen_context
./gen_context
  CC       src/libsecp256k1_la-secp256k1.lo
  CCLD     libsecp256k1.la
/usr/bin/ar: `u' modifier ignored since `D' is the default (see `U')
make[3]: Leaving directory '/home/vertyclank/Downloads/bitcoin-0.20.1/src/secp256k1'
  CXXLD    libbitcoinconsensus.la
/usr/bin/ar: `u' modifier ignored since `D' is the default (see `U')
  CXX      bitcoind-bitcoind.o
  CXX      libbitcoin_server_a-addrdb.o
In file included from ./util/system.h:22:0,
                 from ./addrman.h:15,
                 from addrdb.cpp:8:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-addrman.o
In file included from ./util/system.h:22:0,
                 from ./addrman.h:15,
                 from addrman.cpp:6:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-banman.o
In file included from ./util/system.h:22:0,
                 from banman.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-blockencodings.o
In file included from ./txmempool.h:20:0,
                 from blockencodings.cpp:13:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-blockfilter.o
  CXX      libbitcoin_server_a-chain.o
  CXX      consensus/libbitcoin_server_a-tx_verify.o
  CXX      libbitcoin_server_a-flatfile.o
In file included from ./util/system.h:22:0,
                 from flatfile.cpp:11:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-httprpc.o
In file included from ./util/system.h:22:0,
                 from httprpc.cpp:14:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-httpserver.o
In file included from ./util/system.h:22:0,
                 from httpserver.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      index/libbitcoin_server_a-base.o
In file included from ./util/system.h:22:0,
                 from ./dbwrapper.h:12,
                 from ./index/base.h:8,
                 from index/base.cpp:6:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      index/libbitcoin_server_a-blockfilterindex.o
In file included from ./util/system.h:22:0,
                 from ./dbwrapper.h:12,
                 from index/blockfilterindex.cpp:7:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      index/libbitcoin_server_a-txindex.o
In file included from ./util/system.h:22:0,
                 from ./dbwrapper.h:12,
                 from ./index/base.h:8,
                 from ./index/txindex.h:9,
                 from index/txindex.cpp:5:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      interfaces/libbitcoin_server_a-chain.o
  CXX      interfaces/libbitcoin_server_a-node.o
  CXX      libbitcoin_server_a-init.o
  CXX      libbitcoin_server_a-dbwrapper.o
In file included from ./util/system.h:22:0,
                 from ./dbwrapper.h:12,
                 from dbwrapper.cpp:5:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-miner.o
  CXX      libbitcoin_server_a-net.o
In file included from ./util/system.h:22:0,
                 from ./addrman.h:15,
                 from ./net.h:10,
                 from net.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-net_processing.o
In file included from ./util/system.h:22:0,
                 from ./addrman.h:15,
                 from ./net.h:10,
                 from ./net_processing.h:10,
                 from net_processing.cpp:6:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      node/libbitcoin_server_a-coin.o
In file included from ./txmempool.h:20:0,
                 from node/coin.cpp:8:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      node/libbitcoin_server_a-coinstats.o
In file included from ./txmempool.h:20:0,
                 from ./validation.h:21,
                 from node/coinstats.cpp:11:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      node/libbitcoin_server_a-context.o
  CXX      node/libbitcoin_server_a-psbt.o
  CXX      node/libbitcoin_server_a-transaction.o
In file included from ./util/system.h:22:0,
                 from ./addrman.h:15,
                 from ./net.h:10,
                 from node/transaction.cpp:7:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-noui.o
In file included from ./util/system.h:22:0,
                 from noui.cpp:9:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      policy/libbitcoin_server_a-fees.o
In file included from ./txmempool.h:20:0,
                 from policy/fees.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      policy/libbitcoin_server_a-rbf.o
In file included from ./txmempool.h:20:0,
                 from ./policy/rbf.h:8,
                 from policy/rbf.cpp:5:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      policy/libbitcoin_server_a-settings.o
  CXX      libbitcoin_server_a-pow.o
  CXX      libbitcoin_server_a-rest.o
In file included from ./util/system.h:22:0,
                 from ./dbwrapper.h:12,
                 from ./index/base.h:8,
                 from ./index/txindex.h:9,
                 from rest.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      rpc/libbitcoin_server_a-blockchain.o
In file included from ./util/system.h:22:0,
                 from ./dbwrapper.h:12,
                 from ./index/base.h:8,
                 from ./index/blockfilterindex.h:11,
                 from rpc/blockchain.cpp:16:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      rpc/libbitcoin_server_a-mining.o
In file included from ./miner.h:9:0,
                 from rpc/mining.cpp:14:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      rpc/libbitcoin_server_a-misc.o
In file included from ./script/descriptor.h:8:0,
                 from rpc/misc.cpp:14:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      rpc/libbitcoin_server_a-net.o
In file included from ./util/system.h:22:0,
                 from ./addrman.h:15,
                 from ./net.h:10,
                 from rpc/net.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      rpc/libbitcoin_server_a-rawtransaction.o
  CXX      rpc/libbitcoin_server_a-server.o
In file included from ./util/system.h:22:0,
                 from rpc/server.cpp:12:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      script/libbitcoin_server_a-sigcache.o
In file included from ./util/system.h:22:0,
                 from script/sigcache.cpp:11:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-shutdown.o
  CXX      libbitcoin_server_a-timedata.o
In file included from ./util/system.h:22:0,
                 from timedata.cpp:14:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-torcontrol.o
In file included from ./util/system.h:22:0,
                 from ./addrman.h:15,
                 from ./net.h:10,
                 from torcontrol.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-txdb.o
In file included from ./util/system.h:22:0,
                 from ./dbwrapper.h:12,
                 from ./txdb.h:10,
                 from txdb.cpp:6:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-txmempool.o
In file included from ./txmempool.h:20:0,
                 from txmempool.cpp:6:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-ui_interface.o
  CXX      libbitcoin_server_a-validation.o
In file included from ./txmempool.h:20:0,
                 from ./validation.h:21,
                 from validation.cpp:6:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_server_a-validationinterface.o
  CXX      libbitcoin_server_a-versionbits.o
  CXX      libbitcoin_server_a-dummywallet.o
In file included from ./util/system.h:22:0,
                 from dummywallet.cpp:5:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  AR       libbitcoin_server.a
  CXX      libbitcoin_common_a-base58.o
  CXX      libbitcoin_common_a-bech32.o
  CXX      libbitcoin_common_a-bloom.o
  CXX      libbitcoin_common_a-chainparams.o
In file included from ./util/system.h:22:0,
                 from chainparams.cpp:11:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_common_a-coins.o
  CXX      libbitcoin_common_a-compressor.o
  CXX      libbitcoin_common_a-core_read.o
  CXX      libbitcoin_common_a-core_write.o
In file included from ./util/system.h:22:0,
                 from core_write.cpp:15:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_common_a-key.o
  CXX      libbitcoin_common_a-key_io.o
  CXX      libbitcoin_common_a-merkleblock.o
  CXX      libbitcoin_common_a-netaddress.o
  CXX      libbitcoin_common_a-netbase.o
In file included from ./util/system.h:22:0,
                 from netbase.cpp:12:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_common_a-net_permissions.o
In file included from ./util/system.h:22:0,
                 from net_permissions.cpp:8:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_common_a-outputtype.o
  CXX      policy/libbitcoin_common_a-feerate.o
  CXX      policy/libbitcoin_common_a-policy.o
  CXX      libbitcoin_common_a-protocol.o
In file included from ./util/system.h:22:0,
                 from protocol.cpp:8:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_common_a-psbt.o
In file included from ./psbt.h:10:0,
                 from psbt.cpp:5:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      rpc/libbitcoin_common_a-rawtransaction_util.o
  CXX      rpc/libbitcoin_common_a-util.o
In file included from ./script/descriptor.h:8:0,
                 from rpc/util.cpp:8:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_common_a-scheduler.o
  CXX      script/libbitcoin_common_a-descriptor.o
  CXX      script/libbitcoin_common_a-sign.o
  CXX      script/libbitcoin_common_a-signingprovider.o
In file included from ./util/system.h:22:0,
                 from script/signingprovider.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      script/libbitcoin_common_a-standard.o
  CXX      libbitcoin_common_a-versionbitsinfo.o
  CXX      libbitcoin_common_a-warnings.o
In file included from ./util/system.h:22:0,
                 from warnings.cpp:9:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  AR       libbitcoin_common.a
make[3]: Entering directory '/home/vertyclank/Downloads/bitcoin-0.20.1/src/univalue'
  CXX      lib/libunivalue_la-univalue.lo
  CXX      lib/libunivalue_la-univalue_get.lo
  CXX      lib/libunivalue_la-univalue_read.lo
  CXX      lib/libunivalue_la-univalue_write.lo
  CXXLD    libunivalue.la
ar: `u' modifier ignored since `D' is the default (see `U')
make[3]: Leaving directory '/home/vertyclank/Downloads/bitcoin-0.20.1/src/univalue'
  CXX      support/libbitcoin_util_a-lockedpool.o
  CXX      libbitcoin_util_a-chainparamsbase.o
In file included from ./util/system.h:22:0,
                 from chainparamsbase.cpp:9:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      libbitcoin_util_a-clientversion.o
  CXX      compat/libbitcoin_util_a-glibc_sanity_fdelt.o
  CXX      compat/libbitcoin_util_a-glibc_sanity.o
  CXX      compat/libbitcoin_util_a-glibcxx_sanity.o
  CXX      compat/libbitcoin_util_a-strnlen.o
  CXX      libbitcoin_util_a-fs.o
  CXX      interfaces/libbitcoin_util_a-handler.o
  CXX      libbitcoin_util_a-logging.o
  CXX      libbitcoin_util_a-random.o
  CXX      libbitcoin_util_a-randomenv.o
  CXX      rpc/libbitcoin_util_a-request.o
In file included from ./util/system.h:22:0,
                 from rpc/request.cpp:12:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      support/libbitcoin_util_a-cleanse.o
  CXX      libbitcoin_util_a-sync.o
  CXX      libbitcoin_util_a-threadinterrupt.o
  CXX      util/libbitcoin_util_a-asmap.o
  CXX      util/libbitcoin_util_a-bip32.o
  CXX      util/libbitcoin_util_a-bytevectorhash.o
  CXX      util/libbitcoin_util_a-error.o
In file included from ./util/system.h:22:0,
                 from util/error.cpp:8:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      util/libbitcoin_util_a-fees.o
  CXX      util/libbitcoin_util_a-system.o
  CXX      util/libbitcoin_util_a-message.o
  CXX      util/libbitcoin_util_a-moneystr.o
  CXX      util/libbitcoin_util_a-rbf.o
  CXX      util/libbitcoin_util_a-settings.o
  CXX      util/libbitcoin_util_a-threadnames.o
  CXX      util/libbitcoin_util_a-spanparsing.o
  CXX      util/libbitcoin_util_a-strencodings.o
  CXX      util/libbitcoin_util_a-string.o
  CXX      util/libbitcoin_util_a-time.o
  CXX      util/libbitcoin_util_a-url.o
  AR       libbitcoin_util.a
  CXX      libbitcoin_consensus_a-arith_uint256.o
  CXX      consensus/libbitcoin_consensus_a-merkle.o
  CXX      consensus/libbitcoin_consensus_a-tx_check.o
  CXX      libbitcoin_consensus_a-hash.o
  CXX      primitives/libbitcoin_consensus_a-block.o
  CXX      primitives/libbitcoin_consensus_a-transaction.o
  CXX      libbitcoin_consensus_a-pubkey.o
  CXX      script/libbitcoin_consensus_a-bitcoinconsensus.o
  CXX      script/libbitcoin_consensus_a-interpreter.o
  CXX      script/libbitcoin_consensus_a-script.o
  CXX      script/libbitcoin_consensus_a-script_error.o
  CXX      libbitcoin_consensus_a-uint256.o
  CXX      util/libbitcoin_consensus_a-strencodings.o
  AR       libbitcoin_consensus.a
  CXX      crypto/crypto_libbitcoin_crypto_base_a-aes.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-chacha_poly_aead.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-chacha20.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-hkdf_sha256_32.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-hmac_sha256.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-hmac_sha512.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-poly1305.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-ripemd160.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-sha1.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-sha256.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-sha512.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-siphash.o
  CXX      crypto/crypto_libbitcoin_crypto_base_a-sha256_sse4.o
  AR       crypto/libbitcoin_crypto_base.a
  CXX      crypto/crypto_libbitcoin_crypto_sse41_a-sha256_sse41.o
  AR       crypto/libbitcoin_crypto_sse41.a
  CXX      crypto/crypto_libbitcoin_crypto_avx2_a-sha256_avx2.o
  AR       crypto/libbitcoin_crypto_avx2.a
  CXX      crypto/crypto_libbitcoin_crypto_shani_a-sha256_shani.o
  AR       crypto/libbitcoin_crypto_shani.a
  CXX      leveldb/db/leveldb_libleveldb_a-builder.o
  CXX      leveldb/db/leveldb_libleveldb_a-c.o
  CXX      leveldb/db/leveldb_libleveldb_a-dbformat.o
  CXX      leveldb/db/leveldb_libleveldb_a-db_impl.o
  CXX      leveldb/db/leveldb_libleveldb_a-db_iter.o
  CXX      leveldb/db/leveldb_libleveldb_a-dumpfile.o
  CXX      leveldb/db/leveldb_libleveldb_a-filename.o
  CXX      leveldb/db/leveldb_libleveldb_a-log_reader.o
  CXX      leveldb/db/leveldb_libleveldb_a-log_writer.o
  CXX      leveldb/db/leveldb_libleveldb_a-memtable.o
  CXX      leveldb/db/leveldb_libleveldb_a-repair.o
  CXX      leveldb/db/leveldb_libleveldb_a-table_cache.o
  CXX      leveldb/db/leveldb_libleveldb_a-version_edit.o
  CXX      leveldb/db/leveldb_libleveldb_a-version_set.o
  CXX      leveldb/db/leveldb_libleveldb_a-write_batch.o
  CXX      leveldb/table/leveldb_libleveldb_a-block_builder.o
  CXX      leveldb/table/leveldb_libleveldb_a-block.o
  CXX      leveldb/table/leveldb_libleveldb_a-filter_block.o
  CXX      leveldb/table/leveldb_libleveldb_a-format.o
  CXX      leveldb/table/leveldb_libleveldb_a-iterator.o
  CXX      leveldb/table/leveldb_libleveldb_a-merger.o
  CXX      leveldb/table/leveldb_libleveldb_a-table_builder.o
  CXX      leveldb/table/leveldb_libleveldb_a-table.o
  CXX      leveldb/table/leveldb_libleveldb_a-two_level_iterator.o
  CXX      leveldb/util/leveldb_libleveldb_a-arena.o
  CXX      leveldb/util/leveldb_libleveldb_a-bloom.o
  CXX      leveldb/util/leveldb_libleveldb_a-cache.o
  CXX      leveldb/util/leveldb_libleveldb_a-coding.o
  CXX      leveldb/util/leveldb_libleveldb_a-comparator.o
  CXX      leveldb/util/leveldb_libleveldb_a-crc32c.o
  CXX      leveldb/util/leveldb_libleveldb_a-env.o
  CXX      leveldb/util/leveldb_libleveldb_a-filter_policy.o
  CXX      leveldb/util/leveldb_libleveldb_a-hash.o
  CXX      leveldb/util/leveldb_libleveldb_a-histogram.o
  CXX      leveldb/util/leveldb_libleveldb_a-logging.o
  CXX      leveldb/util/leveldb_libleveldb_a-options.o
  CXX      leveldb/util/leveldb_libleveldb_a-status.o
  CXX      leveldb/util/leveldb_libleveldb_a-env_posix.o
  AR       leveldb/libleveldb.a
  CXX      crc32c/src/crc32c_libcrc32c_a-crc32c.o
  CXX      crc32c/src/crc32c_libcrc32c_a-crc32c_portable.o
  AR       crc32c/libcrc32c.a
  CXX      crc32c/src/crc32c_libcrc32c_sse42_a-crc32c_sse42.o
  AR       crc32c/libcrc32c_sse42.a
  CXX      leveldb/helpers/memenv/leveldb_libmemenv_a-memenv.o
  AR       leveldb/libmemenv.a
  CXXLD    bitcoind
  CXX      bitcoin_cli-bitcoin-cli.o
In file included from ./util/system.h:22:0,
                 from bitcoin-cli.cpp:16:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      compat/libbitcoin_cli_a-stdin.o
  CXX      rpc/libbitcoin_cli_a-client.o
In file included from ./util/system.h:22:0,
                 from rpc/client.cpp:7:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  AR       libbitcoin_cli.a
  CXXLD    bitcoin-cli
  CXX      bitcoin_tx-bitcoin-tx.o
In file included from ./txmempool.h:20:0,
                 from ./policy/rbf.h:8,
                 from bitcoin-tx.cpp:14:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXXLD    bitcoin-tx
  CXX      test/test_test_bitcoin-main.o
In file included from ./txmempool.h:20:0,
                 from ./test/util/setup_common.h:15,
                 from test/main.cpp:12:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
Generated test/data/script_tests.json.h
Generated test/data/base58_encode_decode.json.h
Generated test/data/blockfilters.json.h
Generated test/data/key_io_valid.json.h
Generated test/data/key_io_invalid.json.h
Generated test/data/sighash.json.h
Generated test/data/tx_invalid.json.h
Generated test/data/tx_valid.json.h
Generated test/data/asmap.raw.h
  CXX      test/test_test_bitcoin-arith_uint256_tests.o
  CXX      test/test_test_bitcoin-addrman_tests.o
  CXX      test/test_test_bitcoin-amount_tests.o
  CXX      test/test_test_bitcoin-allocator_tests.o
  CXX      test/test_test_bitcoin-base32_tests.o
  CXX      test/test_test_bitcoin-base58_tests.o
  CXX      test/test_test_bitcoin-base64_tests.o
  CXX      test/test_test_bitcoin-bech32_tests.o
  CXX      test/test_test_bitcoin-bip32_tests.o
  CXX      test/test_test_bitcoin-blockchain_tests.o
  CXX      test/test_test_bitcoin-blockencodings_tests.o
  CXX      test/test_test_bitcoin-blockfilter_tests.o
  CXX      test/test_test_bitcoin-blockfilter_index_tests.o
  CXX      test/test_test_bitcoin-bloom_tests.o
  CXX      test/test_test_bitcoin-bswap_tests.o
  CXX      test/test_test_bitcoin-checkqueue_tests.o
  CXX      test/test_test_bitcoin-coins_tests.o
  CXX      test/test_test_bitcoin-compilerbug_tests.o
  CXX      test/test_test_bitcoin-compress_tests.o
  CXX      test/test_test_bitcoin-crypto_tests.o
  CXX      test/test_test_bitcoin-cuckoocache_tests.o
In file included from ./txmempool.h:20:0,
                 from ./test/util/setup_common.h:15,
                 from test/cuckoocache_tests.cpp:7:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      test/test_test_bitcoin-denialofservice_tests.o
  CXX      test/test_test_bitcoin-descriptor_tests.o
  CXX      test/test_test_bitcoin-flatfile_tests.o
  CXX      test/test_test_bitcoin-fs_tests.o
  CXX      test/test_test_bitcoin-getarg_tests.o
  CXX      test/test_test_bitcoin-hash_tests.o
  CXX      test/test_test_bitcoin-key_io_tests.o
  CXX      test/test_test_bitcoin-key_tests.o
  CXX      test/test_test_bitcoin-limitedmap_tests.o
  CXX      test/test_test_bitcoin-logging_tests.o
  CXX      test/test_test_bitcoin-dbwrapper_tests.o
  CXX      test/test_test_bitcoin-validation_tests.o
  CXX      test/test_test_bitcoin-mempool_tests.o
  CXX      test/test_test_bitcoin-merkle_tests.o
  CXX      test/test_test_bitcoin-merkleblock_tests.o
  CXX      test/test_test_bitcoin-miner_tests.o
  CXX      test/test_test_bitcoin-multisig_tests.o
  CXX      test/test_test_bitcoin-net_tests.o
  CXX      test/test_test_bitcoin-netbase_tests.o
  CXX      test/test_test_bitcoin-pmt_tests.o
  CXX      test/test_test_bitcoin-policyestimator_tests.o
  CXX      test/test_test_bitcoin-pow_tests.o
  CXX      test/test_test_bitcoin-prevector_tests.o
  CXX      test/test_test_bitcoin-raii_event_tests.o
  CXX      test/test_test_bitcoin-random_tests.o
  CXX      test/test_test_bitcoin-reverselock_tests.o
  CXX      test/test_test_bitcoin-rpc_tests.o
  CXX      test/test_test_bitcoin-sanity_tests.o
  CXX      test/test_test_bitcoin-scheduler_tests.o
  CXX      test/test_test_bitcoin-script_p2sh_tests.o
  CXX      test/test_test_bitcoin-script_tests.o
  CXX      test/test_test_bitcoin-script_standard_tests.o
  CXX      test/test_test_bitcoin-scriptnum_tests.o
  CXX      test/test_test_bitcoin-serialize_tests.o
  CXX      test/test_test_bitcoin-settings_tests.o
  CXX      test/test_test_bitcoin-sighash_tests.o
  CXX      test/test_test_bitcoin-sigopcount_tests.o
  CXX      test/test_test_bitcoin-skiplist_tests.o
  CXX      test/test_test_bitcoin-streams_tests.o
  CXX      test/test_test_bitcoin-sync_tests.o
  CXX      test/test_test_bitcoin-util_threadnames_tests.o
  CXX      test/test_test_bitcoin-timedata_tests.o
  CXX      test/test_test_bitcoin-torcontrol_tests.o
  CXX      test/test_test_bitcoin-transaction_tests.o
  CXX      test/test_test_bitcoin-txindex_tests.o
  CXX      test/test_test_bitcoin-txvalidation_tests.o
  CXX      test/test_test_bitcoin-txvalidationcache_tests.o
  CXX      test/test_test_bitcoin-uint256_tests.o
  CXX      test/test_test_bitcoin-util_tests.o
  CXX      test/test_test_bitcoin-validation_block_tests.o
  CXX      test/test_test_bitcoin-validation_flush_tests.o
  CXX      test/test_test_bitcoin-validationinterface_tests.o
  CXX      test/test_test_bitcoin-versionbits_tests.o
  CXX      test/util/libtest_util_a-blockfilter.o
In file included from ./txmempool.h:20:0,
                 from ./validation.h:21,
                 from test/util/blockfilter.cpp:8:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      test/util/libtest_util_a-logging.o
  CXX      test/util/libtest_util_a-mining.o
In file included from ./miner.h:9:0,
                 from test/util/mining.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      test/util/libtest_util_a-net.o
In file included from ./util/system.h:22:0,
                 from ./addrman.h:15,
                 from ./net.h:10,
                 from ./test/util/net.h:8,
                 from test/util/net.cpp:5:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      test/util/libtest_util_a-setup_common.o
In file included from ./txmempool.h:20:0,
                 from ./test/util/setup_common.h:15,
                 from test/util/setup_common.cpp:5:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      test/util/libtest_util_a-str.o
  CXX      test/util/libtest_util_a-transaction_utils.o
  CXX      test/util/libtest_util_a-wallet.o
  AR       libtest_util.a
  CXXLD    test/test_bitcoin
  CXX      bench/bench_bench_bitcoin-bench_bitcoin.o
In file included from ./util/system.h:22:0,
                 from bench/bench_bitcoin.cpp:8:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      bench/bench_bench_bitcoin-bench.o
In file included from ./txmempool.h:20:0,
                 from ./test/util/setup_common.h:15,
                 from bench/bench.cpp:8:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      bench/bench_bench_bitcoin-block_assemble.o
In file included from ./txmempool.h:20:0,
                 from ./test/util/setup_common.h:15,
                 from bench/block_assemble.cpp:9:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      bench/bench_bench_bitcoin-checkblock.o
In file included from ./txmempool.h:20:0,
                 from ./validation.h:21,
                 from bench/checkblock.cpp:9:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      bench/bench_bench_bitcoin-checkqueue.o
In file included from ./util/system.h:22:0,
                 from bench/checkqueue.cpp:6:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
Generated bench/data/block413567.raw.h
  CXX      bench/bench_bench_bitcoin-data.o
  CXX      bench/bench_bench_bitcoin-duplicate_inputs.o
In file included from ./txmempool.h:20:0,
                 from bench/duplicate_inputs.cpp:10:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      bench/bench_bench_bitcoin-examples.o
  CXX      bench/bench_bench_bitcoin-rollingbloom.o
  CXX      bench/bench_bench_bitcoin-chacha20.o
  CXX      bench/bench_bench_bitcoin-chacha_poly_aead.o
  CXX      bench/bench_bench_bitcoin-crypto_hash.o
  CXX      bench/bench_bench_bitcoin-ccoins_caching.o
  CXX      bench/bench_bench_bitcoin-gcs_filter.o
  CXX      bench/bench_bench_bitcoin-merkle_root.o
  CXX      bench/bench_bench_bitcoin-mempool_eviction.o
In file included from ./txmempool.h:20:0,
                 from bench/mempool_eviction.cpp:7:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      bench/bench_bench_bitcoin-mempool_stress.o
In file included from ./txmempool.h:20:0,
                 from bench/mempool_stress.cpp:7:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      bench/bench_bench_bitcoin-rpc_blockchain.o
In file included from ./txmempool.h:20:0,
                 from ./validation.h:21,
                 from bench/rpc_blockchain.cpp:8:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      bench/bench_bench_bitcoin-rpc_mempool.o
In file included from ./txmempool.h:20:0,
                 from bench/rpc_mempool.cpp:7:
./optional.h:24:14: warning: ‘nullopt’ defined but not used [-Wunused-variable]
 static auto& nullopt = boost::none;
              ^
  CXX      bench/bench_bench_bitcoin-util_time.o
  CXX      bench/bench_bench_bitcoin-verify_script.o
  CXX      bench/bench_bench_bitcoin-base58.o
bench/base58.cpp: In function ‘void Base58Decode(benchmark::State&)’:
bench/base58.cpp:50:43: warning: ignoring return value of ‘bool DecodeBase58(const char*, std::vector<unsigned char>&, int)’, declared with attribute warn_unused_result [-Wunused-result]
         (void) DecodeBase58(addr, vch, 64);
                                           ^
  CXX      bench/bench_bench_bitcoin-bech32.o
  CXX      bench/bench_bench_bitcoin-lockedpool.o
  CXX      bench/bench_bench_bitcoin-poly1305.o
  CXX      bench/bench_bench_bitcoin-prevector.o
  CXXLD    bench/bench_bitcoin
make[2]: Leaving directory '/home/vertyclank/Downloads/bitcoin-0.20.1/src'
make[1]: Leaving directory '/home/vertyclank/Downloads/bitcoin-0.20.1/src'
Making all in doc/man
make[1]: Entering directory '/home/vertyclank/Downloads/bitcoin-0.20.1/doc/man'
make[1]: Nothing to be done for 'all'.
make[1]: Leaving directory '/home/vertyclank/Downloads/bitcoin-0.20.1/doc/man'
make[1]: Entering directory '/home/vertyclank/Downloads/bitcoin-0.20.1'
make[1]: Nothing to be done for 'all-am'.
make[1]: Leaving directory '/home/vertyclank/Downloads/bitcoin-0.20.1'

[vertyclank]

Fixed by following this build procedure:

cd depends
make HOST=aarch64-linux-gnu NO_QT=1
cd ..
./autogen.sh
./configure --prefix=$PWD/depends/aarch64-linux-gnu --enable-glibc-back-compat --enable-reduce-exports LDFLAGS=-static-libstdc++
make