What Is the Default Build Configuration Of Cmake?

The default build configuration of CMake is the "Debug" configuration. This configuration is typically used for development and testing purposes, as it includes debugging information and disables optimizations. However, CMake also allows developers to customize the build configuration by specifying options such as "Release" for optimized builds, or "MinSizeRel" for minimal size builds.

How to create a custom default build configuration for a cmake project?

To create a custom default build configuration for a CMake project, follow these steps:

1. Open the CMakeLists.txt file in your project directory.
2. Add a new build configuration using the set command. For example, to create a custom debug configuration, you can add:

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set(CMAKE_BUILD_TYPE "Debug")

1. You can also add custom build options and flags specific to your build configuration using the add_definitions and add_compile_options commands. For example:

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add_definitions(-DDEBUG_MODE)
add_compile_options(-g)

1. Save the changes to the CMakeLists.txt file.
2. Now when you build your project using CMake, the custom default build configuration will be applied automatically.
3. You can also specify the build configuration when running CMake by adding -DCMAKE_BUILD_TYPE=Debug or -DCMAKE_BUILD_TYPE=Release to the command line.

By following these steps, you can easily create a custom default build configuration for your CMake project.

What is the default behavior of cmake when no build type is specified?

The default behavior of CMake when no build type is specified is to use the "RelWithDebInfo" build type. This build type optimizes the code for speed and includes debugging information in the executable. It is a good choice for development and testing purposes.

How to switch between different default build configurations in cmake?

You can switch between different default build configurations in CMake by using the following steps:

1. Create multiple build directories: First, create multiple build directories for each default build configuration. For example, you can create a "Debug" build directory for debugging and a "Release" build directory for the release build.
2. Generate build system files: In each build directory, generate the build system files using the cmake command with the desired build configuration flags. For example, to generate build files for the Release configuration, you can use the command cmake -DCMAKE_BUILD_TYPE=Release .. in the Release build directory.
3. Build the project: Once the build system files are generated, you can build the project using the corresponding build configuration. For example, you can use the cmake --build . command in the Debug build directory to build the project in the Debug configuration.

By following these steps, you can easily switch between different default build configurations in CMake by changing the build configuration flags when generating the build system files in the build directories.

What is the default behavior of cmake when multiple build configurations are specified?

When multiple build configurations are specified in CMake, the first configuration will be used as the default configuration.

For example, if you specify both Debug and Release configurations in your CMakeLists.txt file, the Debug configuration will be used as the default configuration.

You can override this default behavior by setting the CMAKE_BUILD_TYPE variable before running CMake, e.g. cmake -DCMAKE_BUILD_TYPE=Release .