To configure portable parallel builds in CMake, you can use the configure_file
command to generate a configuration file with the desired build settings. Within this configuration file, you can set the number of parallel jobs to be used for building using the MAKE_PROGRAM
variable. This allows you to easily specify the number of jobs to run in parallel during the build process, making your builds faster and more efficient. Additionally, you can also set the BUILD_SHARED_LIBS
variable to determine whether to build shared or static libraries in a portable manner. By using these techniques, you can ensure that your CMake project can be built in a parallel and portable manner across different platforms and environments.
How to create a new CMake target?
To create a new CMake target, you need to follow these steps:
- Add a new executable or library target in your CMakeLists.txt file using the add_executable() or add_library() command.
For example, to create a new executable target named my_executable
, you would add the following line to your CMakeLists.txt file:
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add_executable(my_executable source1.cpp source2.cpp)
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- If your target depends on other libraries or targets, use the target_link_libraries() command to link them to your new target.
For example, if my_executable
depends on a library called my_library
, you would add the following line to your CMakeLists.txt file:
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target_link_libraries(my_executable my_library)
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- Configure any compiler flags or options specific to your new target using the target_compile_options() or target_compile_definitions() commands.
For example, to add -Wall
as a compiler flag for my_executable
, you would add the following line to your CMakeLists.txt file:
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target_compile_options(my_executable PRIVATE -Wall)
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- Run CMake to generate build files for your project with the new target included.
- Build your project with your new target by running make or cmake --build . in the build directory.
Your new target should now be built along with the rest of your project.
What is a CMake variable?
In CMake, a variable is a container that holds a value or a list of values. These variables can be used to store information such as file paths, compiler flags, version numbers, and more. They can be defined, set, modified, and accessed within a CMake script to control various aspects of the build process. Variables in CMake are typically referenced using the ${}
syntax.
What is the meaning of a CMake target?
A CMake target is a logical unit within a CMake build system that represents a single output file created by the build process. Targets can include executables, libraries, or other types of outputs. Targets in CMake can have dependencies on other targets, source files, or custom commands, and are used to organize the build process and specify how different parts of a project relate to each other.
What is the default generator in CMake?
The default generator for CMake is the "Unix Makefiles" generator on Unix-based systems (such as Linux) and "Visual Studio" generator on Windows systems.
How to add compiler flags in CMake?
To add compiler flags in CMake, you can use the add_compile_options
command. Here is an example of how to add compiler flags in CMake:
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# Set compiler flags for C and C++ add_compile_options("-Wall" "-Wextra") # Set compiler flags for specific target target_compile_options(myTarget PRIVATE "-O3") |
In the above example, we add the -Wall
and -Wextra
flags for both C and C++ code. We also add the -O3
optimization flag specifically for the target named myTarget
.
You can add any compiler flags supported by your compiler using the add_compile_options
command in CMake.
What is the usage of the CMake HOWTO guide?
The CMake HOWTO guide is used as a resource for developers who are looking to learn how to use CMake, a popular build system for C and C++ projects. It provides step-by-step instructions and examples on how to create, configure, and build projects using CMake. The guide covers topics such as setting up a basic CMake project, configuring build options, using external libraries, and integrating with other tools. Overall, the CMake HOWTO guide serves as a comprehensive reference for beginners and experienced developers alike to effectively use CMake in their projects.