project_options

A general-purpose CMake library that makes using CMake easier

Usage

Here is a full example:

cmake_minimum_required(VERSION 3.16)

# uncomment to set a default CXX standard for the external tools like clang-tidy and cppcheck
# and the targets that do not specify a standard.
# If not set, the latest supported standard for your compiler is used
# You can later set fine-grained standards for each target using `target_compile_features`
# set(CMAKE_CXX_STANDARD 17)

# Add project_options v0.12.3
# https://github.com/cpp-best-practices/project_options
include(FetchContent)
FetchContent_Declare(_project_options URL https://github.com/cpp-best-practices/project_options/archive/refs/tags/v0.12.3.zip)
FetchContent_MakeAvailable(_project_options)
include(${_project_options_SOURCE_DIR}/Index.cmake)

# uncomment to enable vcpkg:
# # Setup vcpkg - should be called before defining project()
# run_vcpkg()

# Set the project name and language
project(myproject LANGUAGES CXX)

# Initialize project_options variable related to this project
# This overwrites `project_options` and sets `project_warnings`
# uncomment the options to enable them:
project_options(
      ENABLE_CACHE
      ENABLE_CPPCHECK
      ENABLE_CLANG_TIDY
      # WARNINGS_AS_ERRORS
      # ENABLE_CONAN
      # ENABLE_IPO
      # ENABLE_INCLUDE_WHAT_YOU_USE
      # ENABLE_COVERAGE
      # ENABLE_PCH
      # PCH_HEADERS
      # ENABLE_DOXYGEN
      # ENABLE_USER_LINKER
      # ENABLE_BUILD_WITH_TIME_TRACE
      # ENABLE_UNITY
      # ENABLE_SANITIZER_ADDRESS
      # ENABLE_SANITIZER_LEAK
      # ENABLE_SANITIZER_UNDEFINED_BEHAVIOR
      # ENABLE_SANITIZER_THREAD
      # ENABLE_SANITIZER_MEMORY
      # CONAN_OPTIONS
)

# add your executables, libraries, etc. here:

add_executable(myprogram main.cpp)
target_compile_features(myprogram INTERFACE cxx_std_17)
target_link_libraries(myprogram PRIVATE project_options project_warnings) # connect project_options to myprogram

# find and link dependencies (assuming you have enabled vcpkg or Conan):
find_package(fmt REQUIRED)
target_link_system_libraries(
  main
  PRIVATE
  fmt::fmt
)

project_options function

It accepts the following named flags:

• WARNINGS_AS_ERRORS: Treat the warnings as errors
• ENABLE_CPPCHECK: Enable static analysis with Cppcheck
• ENABLE_CLANG_TIDY: Enable static analysis with clang-tidy
• ENABLE_IPO: Enable Interprocedural Optimization (Link Time Optimization, LTO) in the release build
• ENABLE_INCLUDE_WHAT_YOU_USE: Enable static analysis with include-what-you-use
• ENABLE_COVERAGE: Enable coverage reporting for gcc/clang
• ENABLE_CACHE: Enable cache if available
• ENABLE_PCH: Enable Precompiled Headers
• ENABLE_CONAN: Use Conan for dependency management
• ENABLE_DOXYGEN: Enable Doxygen doc builds of source
• ENABLE_USER_LINKER: Enable a specific linker if available
• ENABLE_BUILD_WITH_TIME_TRACE: Enable -ftime-trace to generate time tracing .json files on clang
• ENABLE_UNITY: Enable Unity builds of projects
• ENABLE_SANITIZER_ADDRESS: Enable address sanitizer
• ENABLE_SANITIZER_LEAK: Enable leak sanitizer
• ENABLE_SANITIZER_UNDEFINED_BEHAVIOR: Enable undefined behavior sanitizer
• ENABLE_SANITIZER_THREAD: Enable thread sanitizer
• ENABLE_SANITIZER_MEMORY: Enable memory sanitizer

It gets the following named parameters (each accepting multiple values):

• PCH_HEADERS: the list of the headers to precompile
• MSVC_WARNINGS: Override the defaults for the MSVC warnings
• CLANG_WARNINGS: Override the defaults for the CLANG warnings
• GCC_WARNINGS: Override the defaults for the GCC warnings
• CONAN_OPTIONS: Extra Conan options

run_vcpkg function

Named Option:

• ENABLE_VCPKG_UPDATE: (Disabled by default). If enabled, the vcpkg registry is updated before building (using git pull). As a result, if some of your vcpkg dependencies have been updated in the registry, they will be rebuilt.

Named String:

• VCPKG_DIR: (Defaults to ~/vcpkg). You can provide the vcpkg installation directory using this optional parameter. If the directory does not exist, it will automatically install vcpkg in this directory.

target_link_system_libraries function

A very useful function that accepts the same arguments as target_link_libraries while marking their include directories as "SYSTEM", which suppresses their warnings. This helps in enabling WARNINGS_AS_ERRORS for your own source code.

target_include_system_directories function

Similar to target_include_directories, but it suppresses the warnings. It is useful if you want to include some external directories directly.

Changing the project_options parameters dynamically

It might be useful to change the test and development options on the fly (e.g., to enable sanitizers when running tests). To do this, you can include the GlobalOptions.cmake, which adds global options for the arguments of project_options function.

⚠️ It is highly recommended to keep the build declarative and reproducible by using the function arguments as explained above. The user of your code should not need to pass any special flags to build the library for normal usage. Please do not use this for anything other than test and development.

Click to show the example:

cmake_minimum_required(VERSION 3.16)

# uncomment to set a default CXX standard for the external tools like clang-tidy and cppcheck
# and the targets that do not specify a standard.
# If not set, the latest supported standard for your compiler is used
# You can later set fine-grained standards for each target using `target_compile_features`
# set(CMAKE_CXX_STANDARD 17)

# Add project_options v0.12.3
# https://github.com/cpp-best-practices/project_options
include(FetchContent)
FetchContent_Declare(_project_options URL https://github.com/cpp-best-practices/project_options/archive/refs/tags/v0.12.3.zip)
FetchContent_MakeAvailable(_project_options)
include(${_project_options_SOURCE_DIR}/Index.cmake)

 # ❗ Add global CMake options
include(${_project_options_SOURCE_DIR}/src/GlobalOptions.cmake)

# uncomment to enable vcpkg:
# # Setup vcpkg - should be called before defining project()
# run_vcpkg()

# Set the project name and language
project(myproject LANGUAGES CXX)

# ❗ enable sanitizers if running the tests
option(FEATURE_TESTS "Enable the tests" OFF)
if(FEATURE_TESTS)
    if(CMAKE_SYSTEM_NAME STREQUAL "Windows")
        set(ENABLE_SANITIZER_ADDRESS OFF)
        set(ENABLE_SANITIZER_UNDEFINED_BEHAVIOR OFF)
    else()
        set(ENABLE_SANITIZER_ADDRESS "ENABLE_SANITIZER_ADDRESS")
        set(ENABLE_SANITIZER_UNDEFINED_BEHAVIOR "ENABLE_SANITIZER_UNDEFINED_BEHAVIOR")
    endif()
endif()

# Initialize project_options variable related to this project
# This overwrites `project_options` and sets `project_warnings`
# uncomment the options to enable them:
project_options(
      ENABLE_CACHE
      ENABLE_CPPCHECK
      ENABLE_CLANG_TIDY
      # WARNINGS_AS_ERRORS
      # ENABLE_CONAN
      # ENABLE_IPO
      # ENABLE_INCLUDE_WHAT_YOU_USE
      # ENABLE_COVERAGE
      # ENABLE_PCH
      # PCH_HEADERS
      # ENABLE_DOXYGEN
      # ENABLE_IPO
      # ENABLE_USER_LINKER
      # ENABLE_BUILD_WITH_TIME_TRACE
      # ENABLE_UNITY
      # ❗ Now, the address and undefined behavior sanitizers are enabled through CMake options
      ${ENABLE_SANITIZER_ADDRESS}
      ${ENABLE_SANITIZER_UNDEFINED_BEHAVIOR}
      # ENABLE_SANITIZER_LEAK
      # ENABLE_SANITIZER_THREAD
      # ENABLE_SANITIZER_MEMORY
)
# add your executables, libraries, etc. here:

add_executable(myprogram main.cpp)
target_compile_features(myprogram INTERFACE cxx_std_17)
target_link_libraries(myprogram PRIVATE project_options project_warnings) # connect project_options to myprogram

# find and link dependencies (assuming you have enabled vcpkg or Conan):
find_package(fmt REQUIRED)
target_link_system_libraries(
  main
  PRIVATE
  fmt::fmt
)