cmake 指定输出目录

$ mkdir ~/cpp-netlib-build
$ cd ~/cpp-netlib-build
$ cmake -DCMAKE_BUILD_TYPE=Debug     
>       -DCMAKE_C_COMPILER=clang     
>       -DCMAKE_CXX_COMPILER=clang++ 
>       $HOME/cpp-netlib    # we're assuming this is where cpp-netlib is.

https://github.com/glynos/cpp-netlib