项目A依赖共享库B，B依赖C，A不依赖C。当我使用B的API时，警告B找不到C

Question

项目A依赖于共享库B，B依赖于C，A不依赖于C。B作为共享库进行编译和安装。当A使用B接口时，会出现如下代码所示的B找不到C的警告。

在该代码中，A是LibTest。B是TdLib。C是pangolin。

Scanning dependencies of target LibTest
[ 50%] Building CXX object CMakeFiles/LibTest.dir/main.cpp.o
[100%] Linking CXX executable LibTest
/usr/bin/ld: warning: libpangolin.so, needed by /home/wang/CLionProjects/TdLibrary/install/lib/libTdLib.so, not found (try using -rpath or -rpath-link)
/home/wang/CLionProjects/TdLibrary/install/lib/libTdLib.so: 'pangolin::CreateDisplay()’ undefined reference
...
collect2: error: ld returned 1 exit status
CMakeFiles/LibTest.dir/build.make:84: recipe for target 'LibTest' failed
make[3]: *** [LibTest] Error 1
CMakeFiles/Makefile2:109: recipe for target 'CMakeFiles/LibTest.dir/all' failed
make[2]: *** [CMakeFiles/LibTest.dir/all] Error 2
CMakeFiles/Makefile2:121: recipe for target 'CMakeFiles/LibTest.dir/rule' failed
make[1]: *** [CMakeFiles/LibTest.dir/rule] Error 2
Makefile:131: recipe for target 'LibTest' failed
make: *** [LibTest] Error 2

共享库B的CMakelist.txt。

add_library(TdLib SHARED
        pangolin_tools.cpp
        pangolin_tools.h
        )

#pangolin
find_package(Pangolin REQUIRED)
include_directories(${Pangolin_INCLUDE_DIRS} )

set(HEADER_FILES
        pangolin_tools.h
        )
set_target_properties(TdLib PROPERTIES
        PUBLIC_HEADER
        "${HEADER_FILES}"
        )

target_link_libraries(TdLib PRIVATE
                    ${Pangolin_LIBRARIES}
                    )

install(TARGETS TdLib
        # IMPORTANT: Add the foo library to the "export-set"
        EXPORT ${PROJECT_NAME}Targets
        RUNTIME DESTINATION "${INSTALL_BIN_DIR}" COMPONENT bin
        LIBRARY DESTINATION "${INSTALL_LIB_DIR}" COMPONENT shlib
        PUBLIC_HEADER DESTINATION "${INSTALL_INCLUDE_DIR}/TdLibrary"
        COMPONENT dev)

我通过以下方式安装B

cmake .. -DCMAKE_INSTALL_PREFIX:=/home/wang/CLionProjects/TdLibrary/install
make
make install

项目A的CMakelist.txt。

cmake_minimum_required(VERSION 3.9)
project(LibTest)
set(CMAKE_CXX_STANDARD 11)

#TdLib
set(TdLib_DIR "/home/wang/CLionProjects/TdLibrary/install/lib/CMake/TdLib/")
find_package(TdLib REQUIRED)
include_directories(${TdLib_INCLUDE_DIRS})

add_executable(LibTest main.cpp)
target_link_libraries(LibTest ${TdLib_LIBRARIES}

Answer 1

您肯定会链接到共享库。

在下面的代码中，我将删除PRIVATE关键字：

target_link_libraries(TdLib PRIVATE
                    ${Pangolin_LIBRARIES}
                    )

看看这是否有帮助。在我这方面，我注意到您可以在没有任何target_link_libraries()的情况下链接库，这会迫使您在构建可执行文件时添加库。

我还猜测这个PRIVATE关键字可能并不完全如您所想的那样。