在mac下，make遇错

[luckypoem]

hi。

我运行make,显示：
...
[ 67%] Built target fmt
Scanning dependencies of target vpncore
[ 67%] Linking CXX static library libvpncore.a
ar: no archive members specified
usage: ar -d [-TLsv] archive file ...
ar -m [-TLsv] archive file ...
ar -m [-abiTLsv] position archive file ...
ar -p [-TLsv] archive [file ...]
ar -q [-cTLsv] archive file ...
ar -r [-cuTLsv] archive file ...
ar -r [-abciuTLsv] position archive file ...
ar -t [-TLsv] archive [file ...]
ar -x [-ouTLsv] archive [file ...]
make[2]: *** [vpncore/libvpncore.a] Error 1
make[1]: *** [vpncore/CMakeFiles/vpncore.dir/all] Error 2
make: *** [all] Error 2
yudeMacBook-Air:avpn-master brite$ ls
CMakeCache.txt README.md third_party
CMakeFiles avpn tun2socks.service
CMakeLists.txt bin tun2socks.service.in
LICENSE cmake vpncore
Makefile cmake_install.cmake
yudeMacBook-Air:avpn-master brite$ ls bin
yudeMacBook-Air:avpn-master brite$

如何解决？

[luckypoem]

搜索到这个：https://stackoverflow.com/questions/19829281/cmake-os-x-failure-ar-no-archive-members-specific?rq=1 ，没看懂，作者指点一下？

[microcai]

xcode 没安装全。

[luckypoem]

@microcai
你好。可提供mac上的可执行文件下载吗

[briteming]

@microcai
你说“xcode 没安装全。”，
怎样才算xcode安装全了？