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Triplet variables

This article describes the kmpkg variables that are available to triplet files. A triplet file can also include user defined variables.

See the triplets concept documentation for a high-level view of triplet capabilities.

Variables​

KMPKG_TARGET_ARCHITECTURE​

Specifies the target machine architecture.

Valid options include x86, x64, arm, arm64, arm64ec, s390x, ppc64le, riscv32, riscv64, loongarch32, loongarch64, mips64, and wasm32.

KMPKG_CRT_LINKAGE​

Specifies the desired CRT linkage (for MSVC).

Valid options are dynamic and static.

KMPKG_LIBRARY_LINKAGE​

Specifies the preferred library linkage.

Valid options are dynamic and static. Libraries can ignore this setting if they do not support the preferred linkage type.

KMPKG_BUILD_TYPE​

You can set this value to release to build release-only versions of the ports. By default this value is empty. When this value is empty kmpkg builds release and debug configurations of ports.

KMPKG_CMAKE_SYSTEM_NAME​

Specifies the target platform.

Valid options include any CMake system name, such as:

  • Empty (Windows Desktop for legacy reasons)
  • WindowsStore (Universal Windows Platform)
  • MinGW (Minimalist GNU for Windows)
  • Darwin (Mac OSX)
  • iOS (iOS)
  • Linux (Linux)
  • Emscripten (WebAssembly)

KMPKG_CMAKE_SYSTEM_VERSION​

Specifies the target platform system version.

This field is optional and, if present, will be passed into the build as CMAKE_SYSTEM_VERSION.

See also the CMake documentation for CMAKE_SYSTEM_VERSION

KMPKG_CHAINLOAD_TOOLCHAIN_FILE​

Specifies an alternate CMake toolchain file to use.

This (if set) will override all other compiler detection logic. By default, a toolchain file is selected from scripts/toolchains/ appropriate to the platform.

info

To create a custom toolchain file, it's best to start by including an existing toolchain from ${KMPKG_ROOT}/scripts/toolchains and extend it. This ensures that essential variables set by the kmpkg executable, such as KMPKG_TARGET_ARCHITECTURE, KMPKG_CXX_FLAGS, KMPKG_LINKER_FLAGS, and other variables are forwarded to CMake.

See also the CMake documentation for toolchain files.

KMPKG_CXX_FLAGS​

Sets additional compiler flags to be used when not using KMPKG_CHAINLOAD_TOOLCHAIN_FILE.

This option also has forms for configuration-specific flags and C language flags:

  • KMPKG_CXX_FLAGS
  • KMPKG_CXX_FLAGS_DEBUG
  • KMPKG_CXX_FLAGS_RELEASE
  • KMPKG_C_FLAGS
  • KMPKG_C_FLAGS_DEBUG
  • KMPKG_C_FLAGS_RELEASE

If you set KMPKG_CXX_FLAGS, you also have to set KMPKG_C_FLAGS, and vice-versa. The same is true for the configuration-specific flags. These variables accept a space-delimited string of compiler flags:

set(KMPKG_CXX_FLAGS "/wd4996 -D_CRT_SECURE_NO_WARNINGS")
set(KMPKG_C_FLAGS "/wd4996 -D_CRT_SECURE_NO_WARNINGS")

KMPKG_LINKER_FLAGS​

Sets additional linker flags to be used while building dynamic libraries and executables in the absence of KMPKG_CHAINLOAD_TOOLCHAIN_FILE.

This option also has forms for configuration-specific flags:

  • KMPKG_LINKER_FLAGS
  • KMPKG_LINKER_FLAGS_DEBUG
  • KMPKG_LINKER_FLAGS_RELEASE

KMPKG_MESON_CONFIGURE_OPTIONS​

Set additional Meson configure options that are appended to the configure command (in kmpkg_configure_meson).

This field is optional.

Also available as build-type specific KMPKG_MESON_CONFIGURE_OPTIONS_DEBUG and KMPKG_MESON_CONFIGURE_OPTIONS_RELEASE variables.

KMPKG_MESON_NATIVE_FILE_RELEASE​

Provide an additional configuration dependent file as a meson cross/native file. Can be used to override settings provided by kmpkg since it will be passed after kmpkg's generated cross/native files are passed.

Especially useful to provide your own build_machine and host_machine entries.

KMPKG_MESON_NATIVE_FILE_DEBUG​

See KMPKG_MESON_NATIVE_FILE_RELEASE.

KMPKG_MESON_CROSS_FILE_RELEASE​

See KMPKG_MESON_NATIVE_FILE_RELEASE.

KMPKG_MESON_CROSS_FILE_DEBUG​

See KMPKG_MESON_NATIVE_FILE_RELEASE.

KMPKG_CMAKE_CONFIGURE_OPTIONS​

Sets additional CMake configure options that are appended to the configure command (in kmpkg_cmake_configure).

This field is optional.

Also available as build-type specific KMPKG_CMAKE_CONFIGURE_OPTIONS_DEBUG and KMPKG_CMAKE_CONFIGURE_OPTIONS_RELEASE variables.

KMPKG_CONFIGURE_MAKE_OPTIONS​

Set additional automake/autoconf configure options that are appended to the configure command (in kmpkg_configure_make).

This field is optional.

For example, to skip certain libtool checks that may errantly fail:

set(KMPKG_CONFIGURE_MAKE_OPTIONS "lt_cv_deplibs_check_method=pass_all")

Also available as build-type specific KMPKG_CONFIGURE_MAKE_OPTIONS_DEBUG and KMPKG_CONFIGURE_MAKE_OPTIONS_RELEASE variables.

KMPKG_HASH_ADDITIONAL_FILES​

A list of files to include in the calculation of package ABI hashes.

This field is optional.

Declare any files that affect the contents of a package and should be factored into the calculation of the ABI hash. For example:

  • Files that are included (via include(filepath)) in custom triplets and toolchains.
  • Files that are defined in KMPKG_MESON_(NATIVE|CROSS)_FILE_<CONFIG>

Only the contents and order of the files are considered, the paths of the files do not affect the ABI hash.

set(KMPKG_HASH_ADDITIONAL_FILES
  "${CMAKE_CURRENT_LIST_DIR}/file1.cmake"
  "${CMAKE_CURRENT_LIST_DIR}/meson-cross.txt"
)

KMPKG_POST_PORTFILE_INCLUDES​

A list of CMake files to include after the execution of portfile.cmake.

This field is optional.

The contents and order of the files are used for the ABI hash, the paths of the files do not affect the ABI hash.

set(KMPKG_POST_PORTFILE_INCLUDES
  "${CMAKE_CURRENT_LIST_DIR}/file1.cmake"
  "${CMAKE_CURRENT_LIST_DIR}/file2.cmake"
)

KMPKG_DEP_INFO_OVERRIDE_VARS​

This section covers an experimental feature of kmpkg which may change or be removed at any time.

Replaces the default computed list of triplet "Supports" terms.

This option (if set) will override the default set of terms used for Platform Expression evaluation.

See the "supports" manifest file field documentation for more details.

info

This list is extracted via the kmpkg_get_dep_info helper function.

KMPKG_DISABLE_COMPILER_TRACKING​

warning

Enabling this option is not recommended since it can lead to ABI incompatibility in restored binary packages. See the binary caching documentation to learn more

When this option is set to TRUE, ON, or 1, the compiler will not be tracked as part of the package abis.

This will cause binary caching to reuse builds from older or newer compilers.

Windows-specific Variables​

KMPKG_ENV_PASSTHROUGH​

Instructs kmpkg to allow additional environment variables into the build process.

On Windows, kmpkg builds packages in a special clean environment that is isolated from the current command prompt to ensure build reliability and consistency. This triplet option can be set to a list of additional environment variables that will be added to the clean environment. The values of these environment variables will be hashed into the package abi -- to pass through environment variables without abi tracking, see KMPKG_ENV_PASSTHROUGH_UNTRACKED.

See also the kmpkg env command for how you can inspect the precise environment that will be used.

info

This list is extracted via the kmpkg_get_tags helper function.

KMPKG_ENV_PASSTHROUGH_UNTRACKED​

Instructs kmpkg to allow additional environment variables into the build process without abi tracking.

See KMPKG_ENV_PASSTHROUGH.

KMPKG_VISUAL_STUDIO_PATH​

Specifies the Visual Studio installation to use.

To select the precise combination of Visual Studio instance and toolset version, we walk through the following algorithm:

  1. Determine the setting for KMPKG_VISUAL_STUDIO_PATH from the triplet, or the environment variable KMPKG_VISUAL_STUDIO_PATH, or consider it unset
  2. Determine the setting for KMPKG_PLATFORM_TOOLSET from the triplet or consider it unset
  3. Gather a list of all pairs of Visual Studio instances with all toolsets available in those instances
    • This is ordered first by instance type (Stable, Prerelease, Legacy) and then by toolset version (v143, v142, v141, v140)
  4. Filter the list based on the settings for KMPKG_VISUAL_STUDIO_PATH and KMPKG_PLATFORM_TOOLSET.
  5. Select the best remaining option

The path should be absolute, formatted with backslashes, and have no trailing slash:

set(KMPKG_VISUAL_STUDIO_PATH "C:\\Program Files\\Microsoft Visual Studio\\2022\\Preview")

KMPKG_PLATFORM_TOOLSET​

Specifies the Visual Studio-based C/C++ compiler toolchain to use.

See KMPKG_VISUAL_STUDIO_PATH for the full selection algorithm.

Valid settings:

  • The Visual Studio 2022 platform toolset is v143.
  • The Visual Studio 2019 platform toolset is v142.
  • The Visual Studio 2017 platform toolset is v141.
  • The Visual Studio 2015 platform toolset is v140.

KMPKG_PLATFORM_TOOLSET_VERSION​

Specifies the detailed MSVC C/C++ compiler toolchain to use.

By default, KMPKG_PLATFORM_TOOLSET always chooses the latest installed minor version of the selected toolset. If you need more granularity, you can use this variable. You can specify either a partial or a full version number. Valid values are, for example, 14.25 or 14.27.29110.

KMPKG_LOAD_VCVARS_ENV​

Determines whether kmpkg will search for and use an instance of Visual Studio as part of the triplet environment.

By default, this is ON for Windows triplets that do not specify KMPKG_CHAINLOAD_TOOLCHAIN_FILE. For non-Windows triplets and triplets specifying KMPKG_CHAINLOAD_TOOLCHAIN_FILE, this defaults to OFF.

Linux Variables​

KMPKG_FIXUP_ELF_RPATH​

When this option is set to (true|1|on), kmpkg will add $ORIGIN and $ORIGIN/<path_relative_to_lib> to the RUNPATH header of executables and shared libraries. This allows packages to be relocated on Linux.

MacOS Variables​

KMPKG_INSTALL_NAME_DIR​

Sets the install name used when building macOS dynamic libraries. Default value is @rpath. See the CMake documentation for CMAKE_INSTALL_NAME_DIR for more information.

KMPKG_FIXUP_MACHO_RPATH​

Ensures Mach-O binaries built by kmpkg are relocatable by using relative install names and run-paths.

When set to ON:

  • Modifies absolute LC_LC_ID_DYLIB field to @rpath/<library> for shared library binaries;
  • Modifies absolute LC_RPATH fields to relative @loader_path/<relative/path/to/library> for executable and shared library binaries.
warning

This functionality is enabled by default when KMPKG_TARGET_IS_OSX is TRUE. To disable, explicitly set KMPKG_FIXUP_MACHO_RPATH to OFF in a triplet file.

For more information about dynamic libraries on macOS, refer to the following links:

KMPKG_OSX_DEPLOYMENT_TARGET​

Sets the minimum macOS version for compiled binaries. This also changes what versions of the macOS platform SDK CMake will search for. See the CMake documentation for CMAKE_OSX_DEPLOYMENT_TARGET for more information.

KMPKG_OSX_SYSROOT​

Set the name or path of the macOS platform SDK that will be used by CMake. See the CMake documentation for CMAKE_OSX_SYSROOT for more information.

KMPKG_OSX_ARCHITECTURES​

Set the macOS / iOS target architecture which will be used by CMake. See the CMake documentation for CMAKE_OSX_ARCHITECTURES for more information.

Per-port customization​

The CMake variable PORT will be set when interpreting the triplet file. It can be used to change settings (such as KMPKG_LIBRARY_LINKAGE) on a per-port basis.

Example:

set(KMPKG_LIBRARY_LINKAGE static)
if(PORT MATCHES "qt5-")
    set(KMPKG_LIBRARY_LINKAGE dynamic)
endif()

This will build all the qt5-* ports as dynamic libraries, but every other port as a static library.

For an example in a real project, see https://github.com/Intelight/kmpkg/blob/master/triplets/x86-windows-mixed.cmake.