How to Use Exclude_from_all In Cmake?

In CMake, the exclude_from_all property can be used to exclude a target from the all target, which is the default target built when running the make or ninja command. This can be useful when you have certain targets that you do not want to be built by default.

To use the exclude_from_all property, you can simply set it to TRUE for the target that you want to exclude from the all target. For example:

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add_executable(my_target main.cpp)
set_target_properties(my_target PROPERTIES exclude_from_all TRUE)

In this example, the my_target executable will not be built when running make or ninja, but it can still be built explicitly by specifying its target name.

Overall, using the exclude_from_all property can help you fine-tune which targets are built by default in your CMake project.

What are the benefits of using exclude_from_all in cmake?

Using exclude_from_all in CMake can offer several benefits, including:

1. Improved build time efficiency: By excluding certain targets from the all target, you can reduce the number of targets that need to be built when running make all or a similar command. This can help streamline the build process and save time.
2. Clearer project structure: By marking certain targets as exclude_from_all, you can clearly indicate which targets are meant to be built by default and which are intended for specific purposes or optional builds. This can make the project structure easier to understand and maintain.
3. Simplified testing and packaging: When targets are excluded from the all target, they won't be included in packaging or testing processes by default. This can help ensure that only necessary targets are included in these processes, leading to more efficient and targeted testing and packaging workflows.
4. Improved clarity and organization: By explicitly specifying which targets should be excluded from the all target, you can make your CMakeLists.txt files more organized and easier to understand for yourself and others working on the project. This can help reduce confusion and make it easier to maintain and modify the project in the future.

What is the syntax for using exclude_from_all in cmake?

To use exclude_from_all in CMake, you can specify it in the add_executable or add_library command like this:

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add_executable(my_executable my_source.cpp)
set_target_properties(my_executable PROPERTIES EXCLUDE_FROM_ALL TRUE)

This will exclude the target from the all target, meaning it will not be built by default when you run make.

What is the impact of using exclude_from_all on the overall build process in cmake?

When using exclude_from_all on a target in CMake, it means that the target will not be built as part of the default build process when running "make all" or equivalent. This can have a few impacts on the overall build process:

1. Faster build times: By excluding certain targets from the default build process, the overall build time can be reduced as these targets will not be built unless explicitly specified by the user.
2. Simplified build logic: Excluding certain targets from the default build process can help simplify the build logic by only building the necessary targets and reducing the complexity of the build system.
3. Reduced clutter: Excluding certain targets from the default build process can reduce the clutter in the build output, making it easier to focus on the relevant targets when troubleshooting build issues.

Overall, using exclude_from_all in CMake can help streamline the build process by excluding unnecessary targets from the default build, leading to faster build times and a more organized build output.

What is the relationship between exclude_from_all and the ADD_SUBDIRECTORY command in cmake?

The exclude_from_all property can be used to exclude a target or directory from being built as part of the default ALL target in CMake. This means that the excluded target or directory will not be built when running make or cmake --build, unless specifically specified by the user.

When exclude_from_all is set to TRUE for a directory, any targets added within that directory using the ADD_SUBDIRECTORY command will also be excluded from the default ALL target. This can be useful when you want to have some targets or directories excluded from the default build process.

In summary, exclude_from_all property can be used to exclude targets or directories from the default build process, and when set for a directory, it will also affect any targets added within that directory using the ADD_SUBDIRECTORY command.