CMakeLists.txt
- C++ course
- Advanced
- Lesson 44/83
- 5 min
Learn to write CMakeLists.txt.
CMakeLists.txt structure
Every source directory root has a CMakeLists.txt. This file contains CMake commands. The most common commands are: add_executable (executable target), add_library (library target), target_link_libraries (link a library to a target) and target_include_directories (header search path).
Example: add_library(mylib STATIC utils.cpp) defines a static library. target_link_libraries(myapp PRIVATE mylib) links mylib to the myapp target. PRIVATE means the dependency belongs only to this target. These commands build relationships between targets.
target_link_libraries
The target_link_libraries(target SCOPE library) command links a library to a target. The scope is one of three: PRIVATE (only this target), PUBLIC (target and its users), INTERFACE (only users).
Example: target_link_libraries(myapp PRIVATE mylib). Here myapp uses mylib but another target using myapp does not see mylib. If the library headers are also exposed, use PUBLIC. This distinction ensures dependencies propagate correctly and prevents unnecessary linking.
Practice Link a library to a target
Write a CMakeLists.txt. Define a static library with add_library(mylib STATIC utils.cpp). Define an executable target with add_executable(myapp main.cpp). Link mylib to myapp with target_link_libraries(myapp PRIVATE mylib).
Starter code
# CMakeLists.txt
# Add add_library, add_executable and target_link_librariesSample solution
add_library(mylib STATIC utils.cpp)
add_executable(myapp main.cpp)
target_link_libraries(myapp PRIVATE mylib)Expected output
Target ready
Questions and answers
Review the lesson questions together with their answers. To test yourself, solve the lesson interactively.
1 Complete the executable command
____(myapp main.cpp)add_executable(myapp main.cpp)Explanation: add_executable defines an executable target.
2 What does add_executable do?
- Selects a compiler
- Defines a library
- Adds a header path
- Defines an executable target Correct answer
Explanation: add_executable defines an executable target from source files.
3 Match the command to its role
| Term | Meaning |
|---|---|
add_library |
Library target |
add_executable |
Executable target |
target_link_libraries |
Links a library |
target_include_directories |
Adds header path |