我在这里有一个外部库:
${PROJECT_SOURCE_DIR}/thirdparty/yaml-cpp/
它是由一个Makefile创建的:thirdparty/Makefile
。我正在执行这样的makefile:
add_custom_target(
yaml-cpp
COMMAND make
WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}/thirdparty
)
然后我尝试将库链接到thirdparty/yaml-cpp/build/libyaml-cpp.a
这是不工作的部分:
target_link_libraries(load_balancer_node ${CMAKE_SOURCE_DIR}/thirdparty/yaml-cpp/build/libyaml-cpp.a)
我得到错误:
Target "yaml-cpp" of type UTILITY may not be linked into another target.
One may link only to STATIC or SHARED libraries, or to executables with the
ENABLE_EXPORTS property set.
如何执行makefile并链接.a
文件
所以cmake不能在这里找出依赖项是有道理的:它必须解析makefile并找到输出。你必须告诉它输出的人。我能想到的最好的方法是使用custom_command而不是自定义目标:
add_custom_command(
OUTPUT ${CMAKE_SOURCE_DIR}/thirdparty/yaml-cpp/build/libyaml-cpp.a
COMMAND make
WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}/thirdparty)
add_custom_target(
yaml-cpp
DEPENDS ${CMAKE_SOURCE_DIR}/thirdparty/yaml-cpp/build/libyaml-cpp.a)
...
add_dependencies(load_balancer_node yaml-cpp)
target_link_libraries(load_balancer_node ${CMAKE_SOURCE_DIR}/thirdparty/yaml-cpp/build/libyaml-cpp.a)
虽然我遇到了链接器的问题(愚蠢的windows机器),但cmake在尝试链接之前已经工作并制作了库。