Android cross-compilation errors about leveldown HOT 1 OPEN

~/Library/Android/sdk/ndk/22.1.7171670/toolchains/llvm/prebuilt/darwin-x86_64/bin/armv7a-linux-androideabi24-clang++ -o Release/obj.target/leveldb/deps/leveldb/leveldb-1.20/util/env_posix.o ../deps/leveldb/leveldb-1.20/util/env_posix.cc '-DNODE_GYP_MODULE_NAME=leveldb' '-DUSING_UV_SHARED=1' '-DUSING_V8_SHARED=1' '-DV8_DEPRECATION_WARNINGS=1' '-DV8_DEPRECATION_WARNINGS' '-DV8_IMMINENT_DEPRECATION_WARNINGS' '-D_LARGEFILE_SOURCE' '-D_FILE_OFFSET_BITS=64' '-D__STDC_FORMAT_MACROS' '-DOPENSSL_THREADS' '-DOPENSSL_NO_ASM' '-DSNAPPY=1' '-DLEVELDB_PLATFORM_POSIX=1' '-DOS_ANDROID=1' '-D_REENTRANT=1' '-D_GLIBCXX_USE_C99_MATH' -I/Users/johnnym/railway-private/node_modules/nodejs-mobile-react-native/android/libnode/include/node -I/Users/johnnym/railway-private/node_modules/nodejs-mobile-react-native/android/libnode/src -I/Users/johnnym/railway-private/node_modules/nodejs-mobile-react-native/android/libnode/deps/openssl/config -I/Users/johnnym/railway-private/node_modules/nodejs-mobile-react-native/android/libnode/deps/openssl/openssl/include -I/Users/johnnym/railway-private/node_modules/nodejs-mobile-react-native/android/libnode/deps/uv/include -I/Users/johnnym/railway-private/node_modules/nodejs-mobile-react-native/android/libnode/deps/zlib -I/Users/johnnym/railway-private/node_modules/nodejs-mobile-react-native/android/libnode/deps/v8/include -I../deps/leveldb/leveldb-1.20 -I../deps/leveldb/leveldb-1.20/include -I../deps/snappy/linux -I../deps/snappy/snappy  -fasm-blocks -mpascal-strings -O3 -gdwarf-2 -arch x86_64  -MMD -MF ./Release/.deps/Release/obj.target/leveldb/deps/leveldb/leveldb-1.20/util/env_posix.o.d.raw   -c
clang++: warning: argument unused during compilation: '-arch x86_64' [-Wunused-command-line-argument]