cmake编译有错误啊！

CMake Error at cmake/boost.cmake:100 (MESSAGE):

  You can download it with -DDOWNLOAD_BOOST=1 -DWITH_BOOST=<directory>

  This CMake script will look for boost in <directory>.  If it is not there,

  it will download and unpack it (in that directory) for you.

  If you are inside a firewall, you may need to use an https proxy:

  export https_proxy=http://example.com:80

Call Stack (most recent call first):

  cmake/boost.cmake:288 (COULD_NOT_FIND_BOOST)

  CMakeLists.txt:671 (INCLUDE)