C++ 为什么cmake不在makefile中添加库链接命令？

我喜欢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

，其中只有一个简单的hello world示例，以及

CMakeLists.txt

，其中包含以下文本：

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，但我只是在测试一下

现在，如果我进入

build

目录，并运行

cmake../src

，那么将在

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是否应该添加一行，例如

-lblas

谢谢：）

---

CMake使用一个3级的makefile层次结构。您要查找的行将位于

CMakeFiles/Makefile2

或

build.make

下的

CMakeFiles

（可能还有一个

test

目录）。

如果包含相关头文件/etc。cmake是否更改输出makefile？cmake是否会发现您实际上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

，查看cmake生成的命令是什么

# CMAKE generated file: DO NOT EDIT!
# Generated by "Unix Makefiles" Generator, CMake Version 2.8

# Default target executed when no arguments are given to make.
default_target: all
.PHONY : default_target

#=============================================================================
# Special targets provided by cmake.

# Disable implicit rules so canonical targets will work.
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.PHONY : edit_cache

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