CMake notes
Contents
CMake notes¶
Notes from the field on CMake.
Packages¶
CMake is able to locate packages with the find_package directive. This method operates in two different modes, namely CONFIG and MODULE, and in doing so sets a number of variables, including <PACKAGE>_FOUND, so that we can check that we successfully located the package. The search procedure describes how these packages are resolved. In short, if we are using an internal (i.e. in the project folder located) package, we want to either name the directory identically to the find_package name, else provide the additional name with the NAME flag in find_package. An example use is then
find_package(some_package COMPONENTS component1 component2 NAME alias REQUIRED)
which can then be system agnostically located in some_package/ at root level. Note that each OS may require a different directory hierarchy within the package, but if you are writing one yourself, you need only include, at minimum, a cmake directory within it, containing the Find*.cmake or *Config.cmake files.
Note that the above applies for CONFIG mode. MODULE mode is a more simple use, which will often then define include directories and paths.
In either case, the packages must later be linked with link_libraries or target_link_libraries.