首页 > 解决方案 > 如何指定 target_link_libraries 使用的库的 cmake 路径

问题描述

我有一些具有cmake构建系统的代码库。在构建 iam 时出现如下错误

/usr/bin/ld: cannot find -lcurl

下面是示例cmakelist.txt

cmake_minimum_required(VERSION 2.8.6)
project(oci_object_test)

set(IB_HOME /home/user/sample_cmake/usr/lib)

include_directories(${LIB_HOME}/include)
link_directories(${LIB_HOME}/lib64)

link_directories(/home/user/sample_cmake/usr/lib/lib64)
link_directories(/home/user/)

set(SOURCES
        sample.cpp
)

add_executable(demo ${SOURCES})
target_link_libraries(demo curl openssl) 

以上cmakelist.txtlink.txtcmake生成的

/usr/bin/c++      CMakeFiles/demo.dir/sample.cpp.o  -o demo  -L/home/user/sample_cmake/usr/lib/lib64  -L/home/user -rdynamic -lcurl -lopenssl -Wl,-rpath,/home/user/sample_cmake/usr/lib/lib64:/home/user 

-lcurl这个问题是由于link.txtcmake 生成的。如果我手动删除并构建-lcurllink.txt构建将成功,没有链接器错误。那么有什么办法可以摆脱它-lcurllink.txt或者是否可以定义 -lcurl 路径,它实际存在 libcurl(例如假设 libcurl 存在于内部/usr/curl_path/curl),以便 cmake 可以生成如下所示的 link.txt?

/usr/bin/c++      CMakeFiles/demo.dir/sample.cpp.o  -o demo  -L/home/user/sample_cmake/usr/lib/lib64  -L/home/user -rdynamic /usr/curl_path/curl -lopenssl -Wl,-rpath,/home/user/sample_cmake/usr/lib/lib64:/home/user 

我知道我可以libucrl直接如下定义路径,这将解决我的问题,

target_link_libraries(demo /usr/curl_path/curl openssl) 

但是我正在寻找我可以在 toolchain.cmake 文件中定义的类似SET 或任何其他cmake environment variable内容,以便cmakelist.txt保持不变,in simple words how do i specify those libraries's path to cmake which are going use inside target_link_libraries

标签: cmakelinkerlibcurlld

解决方案


如果您的 CMake 版本低于 3.12,则需要使用这种旧方法。见: https ://cmake.org/cmake/help/v3.10/module/FindCURL.html

cmake_minimum_required(VERSION 3.10)
project(program)

find_package(CURL REQUIRED)

if (CURL_FOUND)
    add_executable(program main.cpp)
    target_link_libraries(program ${CURL_LIBRARIES})
    target_include_directories(program PRIVATE ${CURL_INCLUDE_DIRS})
endif()

CMake 3.12 及更高版本有一种使用导入目标的新方法。请参阅新的替代方法FindCurl

cmake_minimum_required(VERSION 3.12)
project(program)

find_package(CURL REQUIRED)

if (CURL_FOUND)
    add_executable(program main.cpp)
    target_link_libraries(program CURL::libcurl)
endif()

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