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What is CMake policy?
The CMake Policy mechanism is designed to help keep existing projects building as new versions of CMake introduce changes in behavior. Projects may set each policy to select the desired behavior. When CMake needs to know which behavior to use it checks for a setting specified by the project.
Is CMake backwards compatible?
The CMake Policy mechanism provides backwards compatibility as a first-class feature.
What is CMake minimum required?
Set the minimum required version of cmake for a project. The FATAL_ERROR option is accepted but ignored by CMake 2.6 and higher. It should be specified so CMake versions 2.4 and lower fail with an error instead of just a warning.
What is CMake script mode?
Script mode simply runs the commands in the given CMake Language source file and does not generate a build system. It does not allow CMake commands that define build targets or actions.
What does Add_subdirectory do in CMake?
Add a subdirectory to the build. Adds a subdirectory to the build. The source_dir specifies the directory in which the source CMakeLists.
What is Cmake_cxx_flags?
CMAKE_CXX_FLAGS is used to add flags for all C++ targets. That’s handy to pass general arguments like warning levels or to selected required C++ standards. It has no effect on C or Fortran targets and the user might pass additional flags.
How do I run a CMake script?
Running CMake from the command line From the command line, cmake can be run as an interactive question and answer session or as a non-interactive program. To run in interactive mode, just pass the option “-i” to cmake. This will cause cmake to ask you to enter a value for each value in the cache file for the project.
How do I use cmake and make?
Run the cmake executable or the cmake-gui to configure the project and then build it with your chosen build tool. Run the install step by using the install option of the cmake command (introduced in 3.15, older versions of CMake must use make install ) from the command line, or build the INSTALL target from an IDE.
What is the difference between make and cmake?
Make (or rather a Makefile) is a buildsystem – it drives the compiler and other build tools to build your code. CMake is a generator of buildsystems. It can produce Makefiles, it can produce Ninja build files, it can produce KDEvelop or Xcode projects, it can produce Visual Studio solutions.
How to set policy based on CMake version?
Setting Policies by CMake Version ¶ The cmake_policy command is used to set policies to OLD or NEW behavior. While setting policies individually is supported, we encourage projects to set policies based on CMake versions:
Is the old behavior of CMake policy deprecated?
The OLD behavior of a policy is deprecated by definition and may be removed in a future version of CMake. Check whether a given policy is set to OLD or NEW behavior. The output value will be OLD or NEW if the policy is set, and empty otherwise.
How to silence a policy warning in CMake?
Projects depending on the old behavior of a given policy may silence a policy warning by setting the policy state to OLD. Alternatively one may fix the project to work with the new behavior and set the policy state to NEW. The OLD behavior of a policy is deprecated by definition and may be removed in a future version of CMake.
How does the SET command in CMake work?
In this case the set command will add the type. Furthermore, if the is PATH or FILEPATH and the provided on the command line is a relative path, then the set command will treat the path as relative to the current working directory and convert it to an absolute path. Sets an Environment Variable to the given value.