CMake

Question

我有一个变量：

set(${PROJECT_NAME}_EXTERNAL_LIBRARIES
        ${PocoNetExternal_LIBRARIES}
)

来自：

set(EXTERNAL_NAME PocoNetExternal)
    set(${EXTERNAL_NAME}_LIBRARIES
        ${PROJECT_BINARY_DIR}/${EXTERNAL_NAME}/Foundation/${CMAKE_SHARED_LIBRARY_PREFIX}PocoFoundation${POCO_build_postfix}${CMAKE_STATIC_LIBRARY_SUFFIX}
        ${PROJECT_BINARY_DIR}/${EXTERNAL_NAME}/Util/${CMAKE_SHARED_LIBRARY_PREFIX}PocoUtil${POCO_build_postfix}${CMAKE_STATIC_LIBRARY_SUFFIX}
        ${PROJECT_BINARY_DIR}/${EXTERNAL_NAME}/Net/${CMAKE_SHARED_LIBRARY_PREFIX}PocoNet${POCO_build_postfix}${CMAKE_STATIC_LIBRARY_SUFFIX}
       )

由于 This Question 中讨论的问题，我需要所有这些路径都是相对的。

我试过这个：

function(makeLibPathsAbsolute)

    set(temp ${${PROJECT_NAME}_EXTERNAL_LIBRARIES})    #rename list
    set(external_libraries_rel)                        #make empty list

    list(LENGTH temp len1)                 #len1 is length of temp list
    math(EXPR len2 "${len1} - 1")           #len2 is len1 - 1

    foreach(val RANGE ${len2})                                 #for val = 0 to len2
        list(GET temp ${val} relPath)                         #relPath becomes the {val} entry of temp
        get_filename_component(absPath ${relPath} ABSOLUTE)   #make relPath Absolute and call it absPath
        list(APPEND external_libraries_rel ${absPath})        #Append this to the external_libraries_rel list
    endforeach()

endfunction()

但是当我使用 target_link_libraries(${name} ${external_libraries_rel}) 时，我得到了与我尝试 link 的库相关的所有函数的未定义引用错误。表明图书馆实际上还没有 linked.

我的makeLibPathsAbsolute()函数正确吗？

Answer 1

默认情况下，函数中设置的所有变量在外部都是不可见的。（换句话说，变量的定义是作用域函数）。

要使变量对函数的调用者可见，请使用 set() 命令的 PARENT_SCOPE 选项。

例如您可以 "publish" external_libraries_rel 通过将此行附加到函数末尾来列出：

set(external_libraries_rel ${external_libraries_rel} PARENT_SCOPE)

CMake - 制作绝对路径列表。

CMake - Make a list of paths absolute.

path

shared-libraries