编译EOS2.x版本时，由于使用WSL，或者Windows git 操作过，很容易把软连接丢了，所以报错如下
/eos/libraries/chain/webassembly/eos-vm-oc/llvmWARshim.llvmwar:1:1: error: ‘llvmWARshim’ does not name a type
llvmWARshim.cpp
^~~~~~~~~~~
libraries/chain/CMa
手动修复软连接
cd /eos/libraries/chain/webassembly/eos-vm-oc
rm llvmWARshim.llvmwar
ln -s llvmWARshim.cpp llvmWARshim.llvmwar
修复后ll查看如下
llvmWARshim.llvmwar -> llvmWARshim.cpp*