为啥cmake没有在makefile中添加库链接命令？

Posted 2023-02-22

【中文标题】为啥cmake没有在makefile中添加库链接命令？

【英文标题】：Why does cmake not add a library link command in the makefile?为什么cmake没有在makefile中添加库链接命令？

【发布时间】：2015-07-15 15:17:03

【问题描述】：

我是 Ubuntu，我正在学习 cmake 和 make，只是尝试一个简单的例子。我有两个目录：src 和 build。在src 中，我有两个文件：main.cpp，只是一个简单的 hello world 示例，和CMakeLists.txt，带有以下文本：

add_executable(test main.cpp)
target_link_libraries(test blas)

这里，blas 只是我在/usr/lib/libblas.so 找到的一些任意库。我的main.cpp 文件实际上并没有使用它，但我只是在测试......

现在，如果我进入build 目录，并运行cmake ../src，则在build 中生成一个makefile。该 makefile 的内容粘贴在下面。

我感到困惑的是，为什么根本没有提到blas 库？ cmake不应该添加-lblas之类的行吗？

谢谢:)

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【问题讨论】：

如果包含相关的头文件/等。 cmake 会更改输出生成文件吗？ cmake 是否会发现您实际上并不需要该库并忽略它？

如果您尝试调试生成的makefile，您可以运行make VERBOSE=1 并查看cmake 生成的命令是什么

【参考方案1】：

CMake 使用 3 级层次结构的 makefile。您要查找的行将位于CMakeFiles/Makefile2 或build.make 中CMakeFiles 下的某个位置（也可能是test 目录）。