CMakeLists.txt
CMakeLists.txt file contains a set of directives and instructions describing the project's source files and targets (executable, library, or both).
When you create a new project, CLion generates CMakeLists.txt file automatically and places it in the project root directory. To open a project, you can point CLion to the top-level CMakeLists.txt and choose Open as Project.
Example below shows the CMakeLists.txt file of a simple "Hello, World!" project:
cmake_minimum_required(VERSION 3.13) # CMake version check
project(simple_example) # Create project "simple_example"
set(CMAKE_CXX_STANDARD 14) # Enable c++14 standard
# Add main.cpp file of project root directory as source file
set(SOURCE_FILES main.cpp)
# Add executable target with source files listed in SOURCE_FILES variable
add_executable(simple_example ${SOURCE_FILES})
You can edit CMakeLists.txt files right in the Editor. Make sure to reload the project after editing. Automatic reload feature is disabled by default, you can turn it on by selecting the Automatically reload CMake project on editing checkbox in Settings | Build, Execution, Deployment | CMake.
For projects with complex structure, you can create subdirectory CMakeList.txt files to describe the build, contents, and target rules for a subdirectory. Type of a target added by a subdirectory CMakeLists.txt file can differ depending on the role of the module.

When you create a CMake or CMake-based (CUDA, Qt) project via the New Project wizard, CLion uses different templates to generate CMakeLists.txt depending on the project type and settings. You can fine-tune these templates in Settings | Editor | File and Code Templates, the Other tab:

When editing a template text, you can use common predefined variables and the following CMake-specific variables:
${CMAKE_DEFAULT_PROJECT_FILE} | the main.cpp/main.c/libary.cpp/library.c file of the project. |
${CMAKE_LANGUAGE_VERSION} | the selected language standard. |
${CMAKE_MAJOR_VERSION} | the major number of the minimum supported CMake version. For example, if the version if |
${CMAKE_MINOR_VERSION} | the minor number of the minimum supported CMake version. For example, if the version if |
${CMAKE_LIBRARY_TYPE} |
|
${QT_VERSION} | the selected Qt version. |
${REQUIRED_LIBS} | the Qt libraries required for the selected project type. By default, they are |
There is also a template for CMake scripts that you can add to an existing project via New | CMakeLists.txt in the context menu of the project view. By default, this template is empty. You can edit it using the same variables in Settings | Editor | File and Code Templates, the Files tab:

CLion provides code completion for most of the elements in your CMakeLists.txt. For example, you can get the list of the packages bundled with CMake when writing a find_package()
command:

Quick Documentation popup helps you get more information on the elements in your CMake code. To invoke it, use mouse hover or press Ctrl0Q.
For example, you can view quick documentation for completion suggestions:

Folding/unfolding in CMake scripts is available for macros and functions, if-else clauses, comments, as well as arbitrary code selections (make sure to enable Custom folding regions in Settings | Editor | General | Code Folding for this to work).

tip
Press NumPad -/NumPad + to fold or unfold a code fragment
Structure view for CMake shows variables, functions, macros, and targets used your script. To open it, press Alt07 (for the tool window) or CtrlF12 (for the popup).

You can adjust the color and font scheme for CMake files in Settings | Editor | Color Scheme | CMake:

In Settings | Editor | Code Style | CMake, you can adjust the code style being applied to CMake files. When you change a certain setting, the Preview pane shows how this will affect your code.

tip
For general information about code style options in CLion, refer to Code Style.
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