"clang-complete
let g:clang_complete_copen=1
let g:clang_periodic_quickfix=1
let g:clang_snippets=1
let g:clang_close_preview=1
let g:clang_use_library=1
let g:clang_user_options='-stdlib=libstdc++ -std=c++11 -I/usr/include'
let g:clang_library_path='/home/wangnan/develop/clang_llvm/lib