Cmake find_package 須要指定具體的so

須要使用cmake的find_package將boost庫添加到項目中，經過cmake --help-module FindBoost 能夠查看cmake引入Boost的幫助信息：

能夠看到，Boot_LIBRARIES確實是boost相關的庫，剛開始編寫的CMakeLists.txt文件以下：

cmake_minimum_required(VERSION 2.8.4) project(boostCmake) set(CMAKE_CXX_STANDARD 11) set(Boost_DEBUG 1) find_package(Boost) if(Boost_FOUND) MESSAGE("Boost_FOUND") include_directories(${Boost_INCLUDE_DIRS}) link_directories(${Boost_LIBRARIES}) MESSAGE(WARNING "Boost_INCLUDE_DIRS is ${Boost_INCLUDE_DIRS}") add_executable(boostCmake main.cpp) MESSAGE(WARNING "Boost_LIBRARIES is ${Boost_LIBRARY_DIRS}") MESSAGE(WARNING "Boost_LIBRARIES is ${Boost_LIBRARIES}") target_link_libraries(boostCmake ${Boost_LIBRARIES} ) endif()

但是連接一直不成功，MESSAGE(WARNING "Boost_LIBRARIES is ${Boost_LIBRARIES}") 打印的值始終爲空。

這是由於cmake的find_package須要制定具體的library，${Boost_LIBRARIES}纔會有值，要否則就會是空，find_package的正確寫法是：

find_package(Boost 1.54 REQUIRED COMPONENTS system  thread)

這樣能夠看到打印的結果，所須要的庫都找到了，這樣target_link_libraries(boostCmake ${Boost_LIBRARIES}纔會真正的連接到具體的so上，否則就會一直報連接錯誤。

具體工程能夠參考：https://github.com/aktiger/boostCmake.git