NAME

       ycm-build-system-support - YCM Build System Support

YCM BUILD SYSTEM SUPPORT

       YCM offers a few macros and Find scripts that can be used in your build system.

          • Generic  Modules  that  add  functionalities  to  CMake  that might be useful in your
            project.

          • Find Package Modules, that help in finding software on the system.

          • Packaging Helper Modules, that are useful to simplify the  generation  of  a  package
            that can be used by other packages.

          • Support for new CMake features in older CMake versions.

          • Support for new features in CMake before these are actually released.

          • Support for 3rd party CMake modules.

       SEE ALSO:
          You can find for using YCM in your project in ycm-using(7).

       YCM  also offers functionalities to make a superbuild. Documentation for this can be found
       elsewhere.

       SEE ALSO:
          YCM Superbuild

A PRACTICAL EXAMPLE

       Suppose you have created a package that contains a library, called TemplatePkg.  You  want
       to  package  this  library, providing versioning, installation rules for header as well as
       binary files and cmake files for finding and using the library within other projects.

       This is the code you need to add to your CMakeLists.txt:

          cmake_minimum_required(VERSION 3.12)
          project(TemplatePkg
                  LANGUAGES CXX
                  VERSION 0.0.1)

          include(GNUInstallDirs)

          # Set the output dir for binaries
          set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_INSTALL_BINDIR})
          set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_INSTALL_LIBDIR})
          set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_INSTALL_LIBDIR})

          # find and use YCM
          find_package(YCM REQUIRED)

          # Set a few
          set(${PROJECT_NAME}_BUILD_LIBDIR ${CMAKE_INSTALL_LIBDIR})
          set(${PROJECT_NAME}_BUILD_BINDIR ${CMAKE_INSTALL_BINDIR})
          set(${PROJECT_NAME}_BUILD_INCLUDEDIR ${CMAKE_SOURCE_DIR}/src)

          set(${PROJECT_NAME}_INSTALL_LIBDIR ${CMAKE_INSTALL_LIBDIR})
          set(${PROJECT_NAME}_INSTALL_BINDIR ${CMAKE_INSTALL_BINDIR})
          set(${PROJECT_NAME}_INSTALL_INCLUDEDIR ${CMAKE_INSTALL_INCLUDEDIR})

          # add sources
          add_subdirectory(src)

       So far nothing special. We have declared our library, added source codes and included YCM.

       We  now  need  to  instruct  CMake   to   install   the   library   and   generate   CMake
       (FindTemplatePkg.cmake)  have  also  been generated so that TemplatePkg can be found using
       CMake.

          # include macro for installing packaging files and invoke it
          include(InstallBasicPackageFiles)
          install_basic_package_files(TemplatePkg
                                      VARS_PREFIX ${PROJECT_NAME}
                                      VERSION ${${PROJECT_NAME}_VERSION}
                                      COMPATIBILITY SameMajorVersion
                                      NO_CHECK_REQUIRED_COMPONENTS_MACRO)

       This function generates all the configuration files required for other packages to  locate
       and  use  the library compiled by TemplatePkg and adds the required installation rules for
       these files.

       Finally we add uninstall rules:

          include(AddUninstallTarget)

       Now you can compile the package by simply doing:

          mkdir build
          cd build
          cmake ..
          make
          make install

       This will install your package using /usr/local/ as installation prefix.  You  can  change
       the prefix by changing the CMAKE_INSTALL_PREFIX variable, for example

          cmake -DCMAKE_INSTALL_PREFIX:PATH=/opt/ycm ..

       If  you  check inside the build directory or <prefix>/lib you should see that make install
       has built the project and installed header files  and  the  library  correctly.  The  file
       TemplatePkgConfig.cmake  should  be in <prefix>/lib/cmake/TemplatePkg/.  This file will be
       found by other packages when they call:

          find_package(TemplatePkg)

       Example code can be downloaded from TemplatePkg repository.

COPYRIGHT

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