# CMake [www.cmake.org](https://www.cmake.org/) The CMake build system is supported on the following platforms: * FreeBSD * Linux * Microsoft Visual C * MinGW and Msys * macOS, iOS, tvOS, and visionOS with support for XCode * Android * Emscripten * NetBSD * Haiku * Nintendo 3DS * PlayStation 2 * PlayStation Portable * PlayStation Vita * QNX 7.x/8.x * RiscOS ## Building SDL Assuming the source tree of SDL is located at `~/sdl`, this will configure and build SDL in the `~/build` directory: ```sh cmake -S ~/sdl -B ~/build cmake --build ~/build ``` Installation can be done using: ```sh cmake --install ~/build --prefix /usr/local # '--install' requires CMake 3.15, or newer ``` This will install SDL to /usr/local. ### Building SDL tests You can build the SDL test programs by adding `-DSDL_TESTS=ON` to the first cmake command above: ```sh cmake -S ~/sdl -B ~/build -DSDL_TEST_LIBRARY=ON -DSDL_TESTS=ON ``` and then building normally. In this example, the test programs will be built and can be run from `~/build/tests/`. ### Building SDL examples You can build the SDL example programs by adding `-DSDL_EXAMPLES=ON` to the first cmake command above: ```sh cmake -S ~/sdl -B ~/build -DSDL_EXAMPLES=ON ``` and then building normally. In this example, the example programs will be built and can be run from `~/build/examples/`. ## Including SDL in your project SDL can be included in your project in 2 major ways: - using a system SDL library, provided by your (*nix) distribution or a package manager - using a vendored SDL library: this is SDL copied or symlinked in a subfolder. The following CMake script supports both, depending on the value of `MYGAME_VENDORED`. ```cmake cmake_minimum_required(VERSION 3.5) project(mygame) # Create an option to switch between a system sdl library and a vendored SDL library option(MYGAME_VENDORED "Use vendored libraries" OFF) if(MYGAME_VENDORED) # This assumes you have added SDL as a submodule in vendored/SDL add_subdirectory(vendored/SDL EXCLUDE_FROM_ALL) else() # 1. Look for a SDL3 package, # 2. look for the SDL3-shared component, and # 3. fail if the shared component cannot be found. find_package(SDL3 REQUIRED CONFIG REQUIRED COMPONENTS SDL3-shared) endif() # Create your game executable target as usual add_executable(mygame WIN32 mygame.c) # Link to the actual SDL3 library. target_link_libraries(mygame PRIVATE SDL3::SDL3) ``` ### A system SDL library For CMake to find SDL, it must be installed in [a default location CMake is looking for](https://cmake.org/cmake/help/latest/command/find_package.html#config-mode-search-procedure). The following components are available, to be used as an argument of `find_package`. | Component name | Description | |----------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------| | SDL3-shared | The SDL3 shared library, available through the `SDL3::SDL3-shared` target | | SDL3-static | The SDL3 static library, available through the `SDL3::SDL3-static` target | | SDL3_test | The SDL3_test static library, available through the `SDL3::SDL3_test` target | | SDL3 | The SDL3 library, available through the `SDL3::SDL3` target. This is an alias of `SDL3::SDL3-shared` or `SDL3::SDL3-static`. This component is always available. | | Headers | The SDL3 headers, available through the `SDL3::Headers` target. This component is always available. | SDL's CMake support guarantees a `SDL3::SDL3` target. Neither `SDL3::SDL3-shared` nor `SDL3::SDL3-static` are guaranteed to exist. ### Using a vendored SDL This only requires a copy of SDL in a subdirectory + `add_subdirectory`. Alternatively, use [FetchContent](https://cmake.org/cmake/help/latest/module/FetchContent.html). Depending on the configuration, the same targets as a system SDL package are available. ## CMake configuration options ### Build optimized library By default, CMake provides 4 build types: `Debug`, `Release`, `RelWithDebInfo` and `MinSizeRel`. The main difference(s) between these are the optimization options and the generation of debug info. To configure SDL as an optimized `Release` library, configure SDL with: ```sh cmake ~/SDL -DCMAKE_BUILD_TYPE=Release ``` To build it, run: ```sh cmake --build . --config Release ``` ### Shared or static By default, only a dynamic (=shared) SDL library is built and installed. The options `-DSDL_SHARED=` and `-DSDL_STATIC=` accept boolean values to change this. Exceptions exist: - some platforms don't support dynamic libraries, so only `-DSDL_STATIC=ON` makes sense. - a static Apple framework is not supported ### Pass custom compile options to the compiler - Use [`CMAKE__FLAGS`](https://cmake.org/cmake/help/latest/variable/CMAKE_LANG_FLAGS.html) to pass extra flags to the compiler. - Use [`CMAKE_EXE_LINKER_FLAGS`](https://cmake.org/cmake/help/latest/variable/CMAKE_EXE_LINKER_FLAGS.html) to pass extra option to the linker for executables. - Use [`CMAKE_SHARED_LINKER_FLAGS`](https://cmake.org/cmake/help/latest/variable/CMAKE_SHARED_LINKER_FLAGS.html) to pass extra options to the linker for shared libraries. #### Examples - build a SDL library optimized for (more) modern x64 microprocessor architectures. With gcc or clang: ```sh cmake ~/sdl -DCMAKE_C_FLAGS="-march=x86-64-v3" -DCMAKE_CXX_FLAGS="-march=x86-64-v3" ``` With Visual C: ```sh cmake .. -DCMAKE_C_FLAGS="/ARCH:AVX2" -DCMAKE_CXX_FLAGS="/ARCH:AVX2" ``` ### Apple CMake documentation for cross building for Apple: [link](https://cmake.org/cmake/help/latest/manual/cmake-toolchains.7.html#cross-compiling-for-ios-tvos-visionos-or-watchos) #### iOS/tvOS/visionOS CMake 3.14+ natively includes support for iOS, tvOS and watchOS. visionOS requires CMake 3.28+. SDL binaries may be built using Xcode or Make, possibly among other build-systems. When using a compatible version of CMake, it should be possible to: - build SDL dylibs, both static and dynamic dylibs - build SDL frameworks, only shared - build SDL test apps #### Frameworks Configure with `-DSDL_FRAMEWORK=ON` to build a SDL framework instead of a dylib shared library. Only shared frameworks are supported, no static ones. #### Platforms Use `-DCMAKE_PLATFORM_NAME=` to configure the platform. CMake can target only one platform at a time. | Apple platform | `CMAKE_SYSTEM_NAME` value | |-----------------|---------------------------| | macOS (MacOS X) | `Darwin` | | iOS | `iOS` | | tvOS | `tvOS` | | visionOS | `visionOS` | | watchOS | `watchOS` | #### Universal binaries A universal binaries, can be built by configuring CMake with `-DCMAKE_OSX_ARCHITECTURES=`. For example `-DCMAKE_OSX_ARCHITECTURES="arm64;x86_64"` will build binaries that run on both Intel cpus and Apple silicon. SDL supports following Apple architectures: | Platform | `CMAKE_OSX_ARCHITECTURES` value | |----------------------------|---------------------------------| | 64-bit ARM (Apple Silicon) | `arm64` | | x86_64 | `x86_64` | | 32-bit ARM | `armv7s` | CMake documentation: [link](https://cmake.org/cmake/help/latest/variable/CMAKE_OSX_ARCHITECTURES.html) #### Simulators and/or non-default macOS platform SDK Use `-DCMAKE_OSX_SYSROOT=` to configure a different platform SDK. The value can be either the name of the SDK, or a full path to the sdk (e.g. `/full/path/to/iPhoneOS.sdk`). | SDK | `CMAKE_OSX_SYSROOT` value | |----------------------|---------------------------| | iphone | `iphoneos` | | iphonesimulator | `iphonesimulator` | | appleTV | `appletvos` | | appleTV simulator | `appletvsimulator` | | visionOS | `xr` | | visionOS simulator | `xrsimulator` | | watchOS | `watchos` | | watchOS simulator | `watchsimulator` | Append with a version number to target a specific SDK revision: e.g. `iphoneos12.4`, `appletvos12.4`. CMake documentation: [link](https://cmake.org/cmake/help/latest/variable/CMAKE_OSX_SYSROOT.html) #### Examples - for macOS, building a dylib and/or static library for x86_64 and arm64: ```bash cmake ~/sdl -DCMAKE_SYSTEM_NAME=Darwin -DCMAKE_OSX_ARCHITECTURES="x86_64;arm64" -DCMAKE_OSX_DEPLOYMENT_TARGET=10.11 - for macOS, building an universal framework for x86_64 and arm64: ```bash cmake ~/sdl -DSDL_FRAMEWORK=ON -DCMAKE_SYSTEM_NAME=Darwin -DCMAKE_OSX_ARCHITECTURES="x86_64;arm64" -DCMAKE_OSX_DEPLOYMENT_TARGET=10.11 - for iOS-Simulator, using the latest, installed SDK: ```bash cmake ~/sdl -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphonesimulator -DCMAKE_OSX_ARCHITECTURES=x86_64 -DCMAKE_OSX_DEPLOYMENT_TARGET=9.0 ``` - for iOS-Device, using the latest, installed SDK, 64-bit only ```bash cmake ~/sdl -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphoneos -DCMAKE_OSX_ARCHITECTURES=arm64 -DCMAKE_OSX_DEPLOYMENT_TARGET=9.0 ``` - for iOS-Device, using the latest, installed SDK, mixed 32/64 bit ```cmake cmake ~/sdl -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphoneos -DCMAKE_OSX_ARCHITECTURES="arm64;armv7s" -DCMAKE_OSX_DEPLOYMENT_TARGET=9.0 ``` - for iOS-Device, using a specific SDK revision (iOS 12.4, in this example): ```cmake cmake ~/sdl -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphoneos12.4 -DCMAKE_OSX_ARCHITECTURES=arm64 ``` - for iOS-Simulator, using the latest, installed SDK, and building SDL test apps (as .app bundles): ```cmake cmake ~/sdl -DSDL_TESTS=1 -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_SYSROOT=iphonesimulator -DCMAKE_OSX_ARCHITECTURES=x86_64 -DCMAKE_OSX_DEPLOYMENT_TARGET=9.0 ``` - for tvOS-Simulator, using the latest, installed SDK: ```cmake cmake ~/sdl -DCMAKE_SYSTEM_NAME=tvOS -DCMAKE_OSX_SYSROOT=appletvsimulator -DCMAKE_OSX_ARCHITECTURES=x86_64 -DCMAKE_OSX_DEPLOYMENT_TARGET=9.0 ``` - for tvOS-Device, using the latest, installed SDK: ```cmake cmake ~/sdl -DCMAKE_SYSTEM_NAME=tvOS -DCMAKE_OSX_SYSROOT=appletvos -DCMAKE_OSX_ARCHITECTURES=arm64` -DCMAKE_OSX_DEPLOYMENT_TARGET=9.0 ``` - for QNX/aarch64, using the latest, installed SDK: ```cmake cmake ~/sdl -DCMAKE_TOOLCHAIN_FILE=~/sdl/build-scripts/cmake-toolchain-qnx-aarch64le.cmake -DSDL_X11=0 ``` ## SDL-specific CMake options SDL can be customized through (platform-specific) CMake options. The following table shows generic options that are available for most platforms. At the end of SDL CMake configuration, a table shows all CMake options along with its detected value. | CMake option | Valid values | Description | |-------------------------------|--------------|-----------------------------------------------------------------------------------------------------| | `-DSDL_SHARED=` | `ON`/`OFF` | Build SDL shared library (not all platforms support this) (`libSDL3.so`/`libSDL3.dylib`/`SDL3.dll`) | | `-DSDL_STATIC=` | `ON`/`OFF` | Build SDL static library (`libSDL3.a`/`SDL3-static.lib`) | | `-DSDL_TEST_LIBRARY=` | `ON`/`OFF` | Build SDL test library (`libSDL3_test.a`/`SDL3_test.lib`) | | `-DSDL_TESTS=` | `ON`/`OFF` | Build SDL test programs (**requires `-DSDL_TEST_LIBRARY=ON`**) | | `-DSDL_DISABLE_INSTALL=` | `ON`/`OFF` | Don't create a SDL install target | | `-DSDL_DISABLE_INSTALL_DOCS=` | `ON`/`OFF` | Don't install the SDL documentation | | `-DSDL_INSTALL_TESTS=` | `ON`/`OFF` | Install the SDL test programs | ### Incompatibilities #### `SDL_LIBC=OFF` and sanitizers Building with `-DSDL_LIBC=OFF` will make it impossible to use the sanitizer, such as the address sanitizer. Configure your project with `-DSDL_LIBC=ON` to make use of sanitizers. ## CMake FAQ ### CMake fails to build without X11 or Wayland support Install the required system packages prior to running CMake. See [README-linux](linux#build-dependencies) for the list of dependencies on Linux. Other unix operationg systems should provide similar packages. If you **really** don't need to show windows, add `-DSDL_UNIX_CONSOLE_BUILD=ON` to the CMake configure command. ### How do I copy a SDL3 dynamic library to another location? Use [CMake generator expressions](https://cmake.org/cmake/help/latest/manual/cmake-generator-expressions.7.html#target-dependent-expressions). Generator expressions support multiple configurations, and are evaluated during build system generation time. On Windows, the following example copies `SDL3.dll` to the directory where `mygame.exe` is built. ```cmake if(WIN32) add_custom_command( TARGET mygame POST_BUILD COMMAND "${CMAKE_COMMAND}" -E copy $ $ VERBATIM ) endif() ``` On Unix systems, `$` will refer to the dynamic library (or framework), and you might need to use `$` instead. Most often, you can avoid copying libraries by configuring your project with absolute [`CMAKE_LIBRARY_OUTPUT_DIRECTORY`](https://cmake.org/cmake/help/latest/variable/CMAKE_LIBRARY_OUTPUT_DIRECTORY.html) and [`CMAKE_RUNTIME_OUTPUT_DIRECTORY`](https://cmake.org/cmake/help/latest/variable/CMAKE_RUNTIME_OUTPUT_DIRECTORY.html) paths. When using a multi-config generator (such as Visual Studio or Ninja Multi-Config), eventually add `/$` to both paths. ### Linking against a static SDL library fails due to relocation errors On unix platforms, all code that ends up in shared libraries needs to be built as relocatable (=position independent) code. However, by default CMake builds static libraries as non-relocatable. Configuring SDL with `-DCMAKE_POSITION_INDEPENDENT_CODE=ON` will result in a static `libSDL3.a` library which you can link against to create a shared library. ## Help, it doesn't work! Below, a SDL3 CMake project can be found that builds 99.9% of time (assuming you have internet connectivity). When you have a problem with building or using SDL, please modify it until it reproduces your issue. ```cmake cmake_minimum_required(VERSION 3.16) project(sdl_issue) # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! # !!!!!! !!!!!! # !!!!!! This CMake script is not using "CMake best practices". !!!!!! # !!!!!! Don't use it in your project. !!!!!! # !!!!!! !!!!!! # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! # 1. Try system SDL3 package first find_package(SDL3 QUIET) if(SDL3_FOUND) message(STATUS "Using SDL3 via find_package") endif() # 2. Try using a vendored SDL library if(NOT SDL3_FOUND AND EXISTS "${CMAKE_CURRENT_LIST_DIR}/SDL/CMakeLists.txt") add_subdirectory(SDL EXCLUDE_FROM_ALL) message(STATUS "Using SDL3 via add_subdirectory") set(SDL3_FOUND TRUE) endif() # 3. Download SDL, and use that. if(NOT SDL3_FOUND) include(FetchContent) set(SDL_SHARED TRUE CACHE BOOL "Build a SDL shared library (if available)") set(SDL_STATIC TRUE CACHE BOOL "Build a SDL static library (if available)") FetchContent_Declare( SDL GIT_REPOSITORY https://github.com/libsdl-org/SDL.git GIT_TAG main # Replace this with a particular git tag or git hash GIT_SHALLOW TRUE GIT_PROGRESS TRUE ) message(STATUS "Using SDL3 via FetchContent") FetchContent_MakeAvailable(SDL) set_property(DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/_deps/sdl-src" PROPERTY EXCLUDE_FROM_ALL TRUE) endif() file(WRITE main.c [===========================================[ /** * Modify this source such that it reproduces your problem. */ /* START of source modifications */ #include /* * SDL3/SDL_main.h is explicitly not included such that a terminal window would appear on Windows. */ int main(int argc, char *argv[]) { (void)argc; (void)argv; if (!SDL_Init(SDL_INIT_VIDEO)) { SDL_Log("SDL_Init failed (%s)", SDL_GetError()); return 1; } SDL_Window *window = NULL; SDL_Renderer *renderer = NULL; if (!SDL_CreateWindowAndRenderer("SDL issue", 640, 480, 0, &window, &renderer)) { SDL_Log("SDL_CreateWindowAndRenderer failed (%s)", SDL_GetError()); SDL_Quit(); return 1; } while (1) { int finished = 0; SDL_Event event; while (SDL_PollEvent(&event)) { if (event.type == SDL_EVENT_QUIT) { finished = 1; break; } } if (finished) { break; } SDL_SetRenderDrawColor(renderer, 80, 80, 80, SDL_ALPHA_OPAQUE); SDL_RenderClear(renderer); SDL_RenderPresent(renderer); } SDL_DestroyRenderer(renderer); SDL_DestroyWindow(window); SDL_Quit(); return 0; } /* END of source modifications */ ]===========================================]) add_executable(sdl_issue main.c) target_link_libraries(sdl_issue PRIVATE SDL3::SDL3) # target_link_libraries(sdl_issue PRIVATE SDL3::SDL3-shared) # target_link_libraries(sdl_issue PRIVATE SDL3::SDL3-static) ```