This project provides a work-in-progress standalone version of the toolchains and configs used by the Chromium project.
The toolchains have been tested on the following platforms:
- Windows (MSVC 2013/2015/2017/2019/2022, Clang 3.8 - 17.0)
- FreeBSD (GCC 6, Clang 11)
- Linux (GCC 6, Clang 3.8)
- OS X (Xcode 7.3.1)
The testsrc branch contains the test/example project used by the CI tests.
All variables described here are build args and can be overridden in the user's
args.gn
file.
(these variables are available everywhere)
is_debug
(default: true): Toggle between debug and release builds.is_clang
(default: false): Favor Clang over the platform default (GCC/MSVC).is_official_build
(default: !is_debug): Set to enable the official build level of optimization. This enables an additional level of optimization above release (!is_debug).external
(default: "//external"): Label of the external projects directory. By convention, all 3rd-party projects should end up in this directory, so they can depend on each other (e.g. $external/mysql_connector -> $external/zlib)
use_lld
(default: false): Use the new LLD linker. This requiresis_clang
to be true.clang_base_path
(default: ""): The path of your Clang installation folder (without /bin). If you use Clang on Windows, you are required to set this, as the Clang installation isn't automatically detected.
gcc_version
(default: auto-detected): Version of the GCC compiler. Note: Auto-detection is toolchain-specific and happens only if GCC is the active compiler.
Format:major
* 10000minor
* 100patchlevel
clang_version
(default: auto-detected): Version of the Clang compiler. Note: Auto-detection is toolchain-specific and happens only if Clang is the active compiler.
Format:major
* 10000minor
* 100patchlevel
msc_ver
(default: auto-detected): Value of the _MSC_VER variable. See https://msdn.microsoft.com/en-us/library/b0084kay.aspx. Note: Auto-detection happens only when targeting Windows.msc_full_ver
(default: auto-detected): Value of the _MSC_FULL_VER variable. See https://msdn.microsoft.com/en-us/library/b0084kay.aspx. Note: Auto-detection happens only when targeting Windows.
-
visual_studio_version
(default: "latest"): Desired version of Visual Studio. Ifvisual_studio_path
is set, this must be the version of the VS installation at thevisual_studio_path
.Use "2013" for Visual Studio 2013 or "latest" for automatically choosing the highest version (
visual_studio_path
must be unset in this case). -
visual_studio_path
(default: auto-detected): The path of your MSVC installation. If this is set you must set visual_studio_version as well. Autodetected based onvisual_studio_version
. -
windows_sdk_version
(default: auto-detected): Windows SDK version to use. Can either be a full Windows 10 SDK number (e.g. 10.0.10240.0), "8.1" for the Windows 8.1 SDK or "default" for the default SDK selected by VS. -
clang_msc_ver
(default: auto-detected): MSVC versionclang-cl
will report in_MSC_VER
.
This is the default toolchain for POSIX operating systems, which is used for all POSIX systems that don't have special toolchains.
gcc_cc
(default: gcc): Path of the GCC C compiler executable. Does not have to be absolute.gcc_cxx
(default: g ): Path of the GCC C compiler executable. Does not have to be absolute.clang_cc
(default: clang): Path of the Clang C compiler executable. Does not have to be absolute. Note: Ifclang_base_path
is set, the default will beclang_base_path/bin/clang
.clang_cxx
(default: clang ): Path of the Clang C compiler executable. Does not have to be absolute. Note: Ifclang_base_path
is set, the default will beclang_base_path/bin/clang
.
use_system_xcode
(default: true): Use the system install of Xcode for tools like ibtool, libtool, etc. This does not affect the compiler. When this variable is false, targets will instead use a hermetic install of Xcode.hermetic_xcode_path
(default: ""): The path to the hermetic install of Xcode. Only relevant when use_system_xcode = false.use_xcode_clang
(default: true): Compile with Xcode version of clang instead of hermetic version shipped with the build. Iftrue
,clang_base_path
needs to be set.enable_dsyms
(default: true): Produce dSYM files for targets that are configured to do so. dSYM generation is controlled globally as it is a linker output (produced via the//build/toolchain/mac/linker_driver.py
. Enabling this will result in all shared library, loadable module, and executable targets having a dSYM generated.enable_stripping
(default:is_official_build
): Strip symbols from linked targets by default. If this is enabled, the //build/config/mac:strip_all config will be applied to all linked targets. If custom stripping parameters are required, remove that config from a linked target and apply custom-Wcrl,strip
flags. See //build/toolchain/mac/linker_driver.py for more information.
mac_sdk_min
(default: "10.10"): Minimum supported version of the Mac SDK.mac_deployment_target
(default: "10.9"): Minimum supported version of OSX.mac_sdk_path
(default: ""): Path to a specific version of the Mac SDK, not including a slash at the end. If empty, the path to the lowest version greater than or equal tomac_sdk_min
is used.mac_sdk_name
(default: "macosx"): The SDK name as accepted by xcodebuild.
-
ios_sdk_path
(default: ""): Path to a specific version of the iOS SDK, not including a slash at the end. When empty this will use the default SDK based on the value of use_ios_simulator.SDK properties (required when
ios_sdk_path
is non-empty):ios_sdk_name
: The SDK name as accepted by xcodebuild.ios_sdk_version
ios_sdk_platform
ios_sdk_platform_path
xcode_version
xcode_build
machine_os_build
-
ios_deployment_target
(default: "9.0"): Minimum supported version of OSX.
android_ndk_root
(default: "$external/android_tools/ndk"): Path of the Android NDK.android_ndk_version
(default: "r12b"): NDK Version string.android_ndk_major_version
(default: 12): NDK Major version.android_sdk_root
(default: "$external/android_tools/sdk"): Path of the Android SDK.android_sdk_version
(default: "24"): Android SDK version.android_sdk_build_tools_version
(default: "24.0.2"): Version of the Build Tools contained in the SDK.android_libcpp_lib_dir
(default: ""): Libc library directory. Override to use a custom libc binary.use_order_profiling
(default: false): Adds intrumentation to each function. Writes a file with the order that functions are called at startup.
Fork this repo and add it as a submodule/subtree/DEPS
-entry to your project.
This way you can modify every part of the //build
directory while still being
able to easily merge upstream changes (e.g. support for new GN features that
you don't want to implement yourself.)
To ease sharing/composition of projects using this //build
repo,
it is recommended that you refrain from modifying large parts of the toolchains/configs.
If changes are necessary, consider contributing them back ;)
For more complex projects, it might be feasible to use a custom build-config file
that just import()s
//build/config/BUILDCONFIG.gn
and then overrides
the defaults set inside BUILDCONFIG.gn
. There's also GN's default_args
scope, which can be used
to provide project-specific argument overrides.