GN Build Arguments

All builds

active_partition

Current value (from the default): ""

From //build/images/BUILD.gn:48

add_qemu_to_build_archives

Whether to include images necessary to run Fuchsia in QEMU in build archives.

Current value (from the default): false

From //build/images/BUILD.gn:55

additional_bootserver_arguments

Additional bootserver args to add to pave.sh. New uses of this should be added with caution, and ideally discussion. The present use case is to enable throttling of netboot when specific network adapters are combined with specific boards, due to driver and hardware challenges.

Current value (from the default): ""

From //build/images/BUILD.gn:61

all_font_file_paths

List of file paths to every font asset. Populated in fonts.gni.

Current value (from the default): []

From //src/fonts/build/font_args.gni:35

always_zedboot

Build boot images that prefer Zedboot over local boot (only for EFI).

Current value (from the default): false

From //build/images/BUILD.gn:1143

audio_core_trace_enabled

Set to |true| to enable collecting execution traces of audio_core, or |false| to remove all tracing overhead.

Current value (from the default): true

From //src/media/audio/audio_core/BUILD.gn:13

auto_login_to_guest

Whether basemgr should automatically login as a persistent guest user.

Current value (from the default): false

From //src/modular/bin/basemgr/BUILD.gn:14

auto_update_packages

Whether the component loader should automatically update packages.

Current value (from the default): true

From //src/sys/sysmgr/BUILD.gn:10

avb_algorithm

AVB algorithm type.Supported options: SHA256_RSA2048 SHA256_RSA4096 SHA256_RSA8192 SHA512_RSA2048 SHA512_RSA4096 SHA512_RSA8192

Current value (from the default): "SHA512_RSA4096"

From //build/images/vbmeta.gni:29

avb_atx_metadata

AVB metadata which will be used to validate public key

Current value (from the default): ""

From //build/images/vbmeta.gni:20

avb_key

a key which will be used to sign VBMETA and images for AVB

Current value (from the default): ""

From //build/images/vbmeta.gni:17

base_package_labels

If you add package labels to this variable, the packages will be included in the ‘base’ package set, which represents the set of packages that are part of an OTA. These pacakages are updated as an atomic unit during an OTA process and are immutable and are a superset of the TCB (Trusted Computing Base) for a product. These packages are never evicted by the system.

Current value for target_cpu = "arm64": ["//build/info:build-info", "//garnet/bin/device_settings:device_settings_manager", "//garnet/bin/http", "//garnet/bin/log_listener:log_listener", "//garnet/bin/log_listener:log_listener_shell", "//garnet/bin/network_time_service", "//garnet/bin/pkg_cache", "//garnet/bin/pkg_cache:config", "//garnet/bin/pkg_ctl", "//garnet/bin/pkg_resolver", "//garnet/bin/scpi", "//garnet/bin/setui:setui_service", "//garnet/bin/sshd-host", "//garnet/bin/sshd-host:config", "//garnet/bin/stash:stash", "//garnet/bin/stash_ctl:stash_ctl", "//garnet/bin/sysmgr", "//garnet/bin/sysmgr:network_config", "//garnet/bin/sysmgr:services_config", "//garnet/bin/system-update-checker", "//garnet/bin/system-update-checker:system-update-checker-config", "//garnet/bin/thermd", "//garnet/bin/thermd:config", "//garnet/bin/timezone", "//garnet/go/src/amber", "//garnet/go/src/amber:config", "//garnet/go/src/amber:pkgfs", "//garnet/lib/root_ssl_certificates", "//src/diagnostics/archivist:with_default_config", "//src/cobalt/bin/app:cobalt", "//src/cobalt/bin/app:config", "//src/cobalt/bin/system-metrics:cobalt_system_metrics", "//src/connectivity/bluetooth:core", "//src/connectivity/network/mdns/bundles:config", "//src/connectivity/network/mdns/bundles:services", "//src/connectivity/network/net-cli", "//src/connectivity/network/netcfg", "//src/connectivity/network/netcfg:config", "//src/connectivity/network/netcfg:filter_config", "//src/connectivity/network/netstack", "//src/connectivity/wlan:service", "//src/developer/exception_broker", "//src/developer/feedback/boot_log_checker", "//src/developer/feedback/boot_log_checker:config", "//src/developer/feedback/bugreport", "//src/developer/feedback/crashpad_agent", "//src/developer/feedback/feedback_agent", "//src/diagnostics/archivist", "//src/hwinfo:hwinfo", "//src/identity/bin:core", "//src/media/audio/bundles:audio_config", "//src/recovery/factory_reset", "//src/sys/appmgr", "//src/sys/appmgr:appmgr_deprecated_shell_allowlist", "//src/sys/appmgr:appmgr_global_data_allowlist", "//src/sys/appmgr:appmgr_scheme_config", "//src/sys/pkg/bin/update:update-bin", "//src/sys/timekeeper", "//third_party/openssh-portable/fuchsia/developer-keys:ssh_config", "//bundles:kitchen_sink"]

From //root_build_dir/args.gn:3

Overridden from the default: []

From //BUILD.gn:19

Current value for target_cpu = "x64": ["//build/info:build-info", "//garnet/bin/device_settings:device_settings_manager", "//garnet/bin/http", "//garnet/bin/log_listener:log_listener", "//garnet/bin/log_listener:log_listener_shell", "//garnet/bin/network_time_service", "//garnet/bin/pkg_cache", "//garnet/bin/pkg_cache:config", "//garnet/bin/pkg_ctl", "//garnet/bin/pkg_resolver", "//garnet/bin/scpi", "//garnet/bin/setui:setui_service", "//garnet/bin/sshd-host", "//garnet/bin/sshd-host:config", "//garnet/bin/stash:stash", "//garnet/bin/stash_ctl:stash_ctl", "//garnet/bin/sysmgr", "//garnet/bin/sysmgr:network_config", "//garnet/bin/sysmgr:services_config", "//garnet/bin/system-update-checker", "//garnet/bin/system-update-checker:system-update-checker-config", "//garnet/bin/thermd", "//garnet/bin/thermd:config", "//garnet/bin/timezone", "//garnet/go/src/amber", "//garnet/go/src/amber:config", "//garnet/go/src/amber:pkgfs", "//garnet/lib/root_ssl_certificates", "//src/diagnostics/archivist:with_default_config", "//src/cobalt/bin/app:cobalt", "//src/cobalt/bin/app:config", "//src/cobalt/bin/system-metrics:cobalt_system_metrics", "//src/connectivity/bluetooth:core", "//src/connectivity/network/mdns/bundles:config", "//src/connectivity/network/mdns/bundles:services", "//src/connectivity/network/net-cli", "//src/connectivity/network/netcfg", "//src/connectivity/network/netcfg:config", "//src/connectivity/network/netcfg:filter_config", "//src/connectivity/network/netstack", "//src/connectivity/wlan:service", "//src/developer/exception_broker", "//src/developer/feedback/boot_log_checker", "//src/developer/feedback/boot_log_checker:config", "//src/developer/feedback/bugreport", "//src/developer/feedback/crashpad_agent", "//src/developer/feedback/feedback_agent", "//src/diagnostics/archivist", "//src/hwinfo:hwinfo", "//src/identity/bin:core", "//src/media/audio/bundles:audio_config", "//src/recovery/factory_reset", "//src/sys/appmgr", "//src/sys/appmgr:appmgr_deprecated_shell_allowlist", "//src/sys/appmgr:appmgr_global_data_allowlist", "//src/sys/appmgr:appmgr_scheme_config", "//src/sys/pkg/bin/update:update-bin", "//src/sys/timekeeper", "//third_party/openssh-portable/fuchsia/developer-keys:ssh_config", "//bundles:kitchen_sink"]

From //root_build_dir/args.gn:3

Overridden from the default: []

From //BUILD.gn:19

blob_blobfs_maximum_bytes

For build/images:fvm.blob.sparse.blk, use this argument.

Current value (from the default): ""

From //build/images/fvm.gni:70

blob_blobfs_minimum_data_bytes

For build/images:fvm.blob.sparse.blk, use this argument.

Current value (from the default): ""

From //build/images/fvm.gni:56

blob_blobfs_minimum_inodes

For build/images:fvm.blob.sparse.blk, use this argument.

Current value (from the default): ""

From //build/images/fvm.gni:45

blobfs_maximum_bytes

In addition to reserving space for inodes and data, fs needs additional space for maintaining some internal data structures. So the space required to reserve inodes and data may exceed sum of the space needed for inodes and data. maximum_bytes puts an upper bound on the total bytes reserved for inodes, data bytes and reservation for all other internal fs metadata. An empty string does not put any upper bound. A filesystem may reserve few blocks required for its operations.

Current value (from the default): ""

From //build/images/fvm.gni:66

blobfs_minimum_data_bytes

Number of bytes to reserve for data in the fs. This is in addition to what is reserved, if any, for the inodes. Data bytes constitutes “usable” space of the fs. An empty string does not reserve any additional space than minimum required for the filesystem.

Current value (from the default): ""

From //build/images/fvm.gni:52

blobfs_minimum_inodes

minimum_inodes is the number of inodes to reserve for the fs An empty string does not reserve any additional space than minimum required for the filesystem.

Current value (from the default): ""

From //build/images/fvm.gni:41

board_has_libvulkan_arm_mali

Board files can set this to true if they have a package with a mali libvulkan VCD.

Current value (from the default): false

From //garnet/lib/magma/gnbuild/magma.gni:46

board_kernel_cmdline_args

List of kernel command line this board to bake into the boot image that are required by this board. See also kernel_cmdline_args in //build/images/BUILD.gn

Current value (from the default): []

From //build/board.gni:16

board_name

Board name used for paving and amber updates.

Current value for target_cpu = "arm64": "qemu-arm64"

From //boards/arm64.gni:7

Overridden from the default: ""

From //build/board.gni:7

Current value for target_cpu = "x64": "pc"

From //boards/x64.gni:7

Overridden from the default: ""

From //build/board.gni:7

board_package_labels

A list of package labels to include in the ‘base’ package set. Used by the board definition rather than the product definition.

Current value for target_cpu = "arm64": ["//garnet/packages/prod:drivers", "//src/media/audio/bundles:virtual_audio_driver"]

From //boards/arm64.gni:9

Overridden from the default: []

From //build/board.gni:11

Current value for target_cpu = "x64": ["//garnet/packages/prod:drivers", "//src/media/audio/bundles:virtual_audio_driver"]

From //boards/x64.gni:9

Overridden from the default: []

From //build/board.gni:11

board_zedboot_cmdline_args

List of kernel command line arguments to bake into the zedboot image that are required by this board. See also zedboot_cmdline_args in //build/images/zedboot/BUILD.gn

Current value (from the default): []

From //build/board.gni:21

bootfs_allowlist_recovery

List of binaries to include in the bootfs manifest for recovery. This overrides the option set by bootfs_zircon_groups so that only the requested binaries are included in the final image.

Current value (from the default): []

From //build/images/recovery/BUILD.gn:15

bootfs_extra

List of extra manifest entries for files to add to the BOOTFS. Each entry can be a “TARGET=SOURCE” string, or it can be a scope with sources and outputs in the style of a copy() target: outputs[0] is used as TARGET (see gn help source_expansion).

Current value (from the default): []

From //build/images/BUILD.gn:524

bootfs_only

Put the “system image” package in the BOOTFS. Hence what would otherwise be /system/... at runtime is /boot/... instead.

Current value for target_cpu = "arm64": false

From //products/core.gni:7

Overridden from the default: false

From //build/images/boot.gni:15

Current value for target_cpu = "x64": false

From //products/core.gni:7

Overridden from the default: false

From //build/images/boot.gni:15

bootloader_hw_revision

HW revision of the bootloader to be included into OTA package and paving process.

Current value (from the default): ""

From //build/images/BUILD.gn:538

bootloader_prebuilt

Prebuilt bootloader image to be included into update (OTA) package and paving process.

Current value (from the default): ""

From //build/images/BUILD.gn:534

build_all_vp9_file_decoder_conformance_tests

Current value (from the default): false

From //garnet/examples/media/BUILD.gn:10

build_info_board

Board configuration of the current build

Current value (from the default): "qemu-arm64"

From //build/info/info.gni:12

build_info_product

Product configuration of the current build

Current value (from the default): ""

From //build/info/info.gni:9

build_info_version

Logical version of the current build. If not set, defaults to the timestamp of the most recent update.

Current value (from the default): ""

From //build/info/info.gni:16

build_libvulkan_arm_mali

Targets that will be built as mali vulkan ICDS.

Current value (from the default): []

From //garnet/lib/magma/gnbuild/magma.gni:34

build_libvulkan_goldfish

This is a list of targets that will be built as goldfish vulkan ICDs.

Current value (from the default): []

From //garnet/lib/goldfish-vulkan/gnbuild/BUILD.gn:15

build_libvulkan_img_rgx

Targets that will be built as IMG vulkan ICDS.

Current value (from the default): []

From //garnet/lib/magma/gnbuild/magma.gni:43

build_libvulkan_qcom_adreno

Targets that will be built as qualcomm vulkan ICDS.

Current value (from the default): []

From //garnet/lib/magma/gnbuild/magma.gni:40

build_libvulkan_vsl_gc

Targets that will be built as verisilicon vulkan ICDS.

Current value (from the default): []

From //garnet/lib/magma/gnbuild/magma.gni:37

build_sdk_archives

Whether to build SDK tarballs.

Current value (from the default): false

From //build/sdk/config.gni:7

cache_package_labels

If you add package labels to this variable, the packages will be included in the ‘cache’ package set, which represents an additional set of software that is made available on disk immediately after paving and in factory flows. These packages are not updated with an OTA, but instead are updated ephemerally. This cache of software can be evicted by the system if storage pressure arises or other policies indicate.

Current value for target_cpu = "arm64": []

From //products/core.gni:81

Overridden from the default: []

From //BUILD.gn:27

Current value for target_cpu = "x64": []

From //products/core.gni:81

Overridden from the default: []

From //BUILD.gn:27

check_production_eligibility

Whether to perform check on the build's eligibility for production. If true, base_packages and cache_packages are checked against dependencies on :non_production_tag, which is used to tag any non-production GN labels. Build will fail if such dependency is found.

Current value (from the default): false

From //build/images/BUILD.gn:67

clang_lib_dir

Path to Clang lib directory.

Current value (from the default): "../build/prebuilt/third_party/clang/linux-x64/lib"

From //build/images/manifest.gni:19

clang_prefix

The default clang toolchain provided by the prebuilt. This variable is additionally consumed by the Go toolchain.

Current value (from the default): "../prebuilt/third_party/clang/linux-x64/bin"

From //build/config/clang/clang.gni:12

cobalt_environment

Selects the Cobalt environment to send data to. Choices: “LOCAL” - record log data locally to a file “DEVEL” - the non-prod environment for use in testing “PROD” - the production environment “DEVEL_AND_PROD” - both the non-prod and production environment TODO(camrdale): change the default to PROD once its pipeline is working.

Current value (from the default): "DEVEL_AND_PROD"

From //src/cobalt/bin/app/BUILD.gn:17

concurrent_dart_jobs

Maximum number of Dart processes to run in parallel.

Dart analyzer uses a lot of memory which may cause issues when building with many parallel jobs e.g. when using goma. To avoid out-of-memory errors we explicitly reduce the number of jobs.

Current value (from the default): 16

From //build/dart/BUILD.gn:15

concurrent_go_jobs

Maximum number of Go processes to run in parallel.

Current value (from the default): 16

From //build/go/BUILD.gn:11

concurrent_link_jobs

Maximum number of concurrent link jobs.

We often want to run fewer links at once than we do compiles, because linking is memory-intensive. The default to use varies by platform and by the amount of memory available, so we call out to a script to get the right value.

Current value (from the default): 16

From //build/toolchain/BUILD.gn:15

concurrent_rust_jobs

Maximum number of Rust processes to run in parallel.

We run multiple rustc jobs in parallel, each of which can cause significant amount of memory, especially when using LTO. To avoid out-of-memory errors we explicitly reduce the number of jobs.

Current value (from the default): 14

From //build/rust/BUILD.gn:15

crash_diagnostics_dir

Clang crash reports directory path. Use empty path to disable altogether.

Current value (from the default): "//root_build_dir/clang-crashreports"

From //build/config/BUILD.gn:10

crashpad_dependencies

Current value (from the default): "fuchsia"

From //third_party/crashpad/build/crashpad_buildconfig.gni:22

crashpad_use_boringssl_for_http_transport_socket

Current value (from the default): true

From //third_party/crashpad/util/net/tls.gni:22

create_kernel_service_snapshot

Current value (from the default): false

From //third_party/dart/runtime/runtime_args.gni:104

current_cpu

Current value (from the default): ""

current_os

Current value (from the default): ""

custom_signing_script

If non-empty, the given script will be invoked to produce a signed ZBI image. The given script must accept -z for the input zbi path, and -o for the output signed zbi path. The path must be in GN-label syntax (i.e. starts with //).

Current value (from the default): ""

From //build/images/custom_signing.gni:12

dart_component_kind

Current value (from the default): "static_library"

From //third_party/dart/runtime/runtime_args.gni:80

dart_core_snapshot_kind

Controls the kind of core snapshot linked into the standalone VM. Using a core-jit snapshot breaks the ability to change various flags that affect code generation.

Current value (from the default): "core"

From //third_party/dart/runtime/runtime_args.gni:56

dart_custom_version_for_pub

When this argument is a non-empty string, the version repoted by the Dart VM will be one that is compatible with pub's interpretation of semantic version strings. The version string will also include the values of the argument. In particular the version string will read:

"M.m.p-dev.x.x-$(dart_custom_version_for_pub)-$(short_git_hash)"

Where ‘M’, ‘m’, and ‘p’ are the major, minor and patch version numbers, and ‘dev.x.x’ is the dev version tag most recently preceeding the current revision. The short git hash can be omitted by setting dart_version_git_info=false

Current value (from the default): ""

From //third_party/dart/runtime/runtime_args.gni:73

dart_debug

Instead of using is_debug, we introduce a different flag for specifying a Debug build of Dart so that clients can still use a Release build of Dart while themselves doing a Debug build.

Current value (from the default): false

From //third_party/dart/runtime/runtime_args.gni:9

dart_debug_optimization_level

The optimization level to use for debug builds. Defaults to 0 for builds with code coverage enabled.

Current value (from the default): "2"

From //third_party/dart/runtime/runtime_args.gni:36

dart_default_app

Controls whether dart_app() targets generate JIT or AOT Dart snapshots. This defaults to JIT, use `fx set --args ‘dart_default_app=“dart_aot_app”’ to switch to AOT.

Current value (from the default): "dart_jit_app"

From //topaz/runtime/dart/dart_component.gni:19

dart_enable_wasm

Whether dart:wasm should be enabled.

Current value (from the default): false

From //third_party/dart/runtime/runtime_args.gni:94

dart_force_product

Forces all Dart and Flutter apps to build in a specific configuration that we use to build products.

Current value (from the default): false

From //topaz/runtime/dart/config.gni:10

dart_lib_export_symbols

Whether libdart should export the symbols of the Dart API.

Current value (from the default): true

From //third_party/dart/runtime/runtime_args.gni:91

dart_platform_bytecode

Controls whether the VM uses bytecode.

Current value (from the default): false

From //third_party/dart/runtime/runtime_args.gni:84

dart_runtime_mode

Set the runtime mode. This affects how the runtime is built and what features it has. Valid values are: ‘develop’ (the default) - VM is built to run as a JIT with all development features enabled. ‘profile’ - The VM is built to run with AOT compiled code with only the CPU profiling features enabled. ‘release’ - The VM is built to run with AOT compiled code with no developer features enabled.

These settings are only used for Flutter, at the moment. A standalone build of the Dart VM should leave this set to “develop”, and should set ‘is_debug’, ‘is_release’, or ‘is_product’.

TODO(rmacnak): dart_runtime_mode no longer selects whether libdart is build for JIT or AOT, since libdart waw split into libdart_jit and libdart_precompiled_runtime. We should remove this flag and just set dart_debug/dart_product.

Current value (from the default): "develop"

From //third_party/dart/runtime/runtime_args.gni:28

dart_snapshot_kind

Current value (from the default): "kernel"

From //third_party/dart/utils/application_snapshot.gni:14

dart_space_dart

Whether experimental space dart mode is enabled for Dart applications.

Current value (from the default): false

From //topaz/runtime/dart/dart_component.gni:35

dart_target_arch

Explicitly set the target architecture to use a simulator. Available options are: arm, arm64, x64, ia32.

Current value (from the default): "arm64"

From //third_party/dart/runtime/runtime_args.gni:32

dart_use_crashpad

Whether to link Crashpad library for crash handling. Only supported on Windows for now.

Current value (from the default): false

From //third_party/dart/runtime/runtime_args.gni:51

dart_use_fallback_root_certificates

Whether to fall back to built-in root certificates when they cannot be verified at the operating system level.

Current value (from the default): false

From //third_party/dart/runtime/runtime_args.gni:43

dart_use_tcmalloc

Whether to link the standalone VM against tcmalloc. The standalone build of the VM enables this only for Linux builds.

Current value (from the default): false

From //third_party/dart/runtime/runtime_args.gni:47

dart_version_git_info

Whether the Dart binary version string should include the git hash and git commit time.

Current value (from the default): true

From //third_party/dart/runtime/runtime_args.gni:60

dart_vm_code_coverage

Whether to enable code coverage for the standalone VM.

Current value (from the default): false

From //third_party/dart/runtime/runtime_args.gni:39

data_partition_manifest

Path to manifest file containing data to place into the initial /data partition.

Current value (from the default): ""

From //build/images/BUILD.gn:31

debian_guest_earlycon

Current value (from the default): false

From //src/virtualization/packages/debian_guest/BUILD.gn:10

debian_guest_qcow

Package the rootfs as a QCOW image (as opposed to a flat file).

Current value (from the default): true

From //src/virtualization/packages/debian_guest/BUILD.gn:9

devmgr_config

List of arguments to add to /boot/config/devmgr. These come after synthesized arguments to configure blobfs and pkgfs.

Current value (from the default): []

From //build/images/BUILD.gn:507

enable_api_diff

Detect dart API changes TODO(fxb/36723, fxb/6623) Remove this flag once issues are resolved

Current value (from the default): false

From //build/dart/dart_library.gni:17

enable_dart_analysis

Enable all dart analysis

Current value (from the default): true

From //build/dart/dart_library.gni:13

enable_frame_pointers

Controls whether the compiler emits full stack frames for function calls. This reduces performance but increases the ability to generate good stack traces, especially when we have bugs around unwind table generation. It applies only for Fuchsia targets (see below where it is unset).

TODO(ZX-2361): Theoretically unwind tables should be good enough so we can remove this option when the issues are addressed.

Current value (from the default): true

From //build/config/BUILD.gn:20

enable_gfx_subsystem

Current value (from the default): true

From //src/ui/scenic/bin/BUILD.gn:11

enable_input_subsystem

Current value (from the default): true

From //src/ui/scenic/bin/BUILD.gn:12

enable_mdns_trace

Enables the tracing feature of mdns, which can be turned on using “mdns-util verbose”.

Current value (from the default): false

From //src/connectivity/network/mdns/service/BUILD.gn:15

enable_netboot

Whether to build the netboot zbi by default.

You can still build //build/images:netboot explicitly even if enable_netboot is false.

Current value (from the default): false

From //build/images/BUILD.gn:36

escher_use_null_vulkan_config_on_host

Using Vulkan on host (i.e. Linux) is an involved affair that involves downloading the Vulkan SDK, setting environment variables, and so forth... all things that are difficult to achieve in a CQ environment. Therefore, by default we use a stub implementation of Vulkan which fails to create a VkInstance. This allows everything to build, and also allows running Escher unit tests which don't require Vulkan.

Current value (from the default): true

From //src/ui/lib/escher/build_args.gni:12

escher_use_runtime_glsl

Determines whether or not escher will build with the glslang and shaderc libraries. When false, these libraries will not be included in the scenic/ escher binary and as a result shaders will not be able to be compiled at runtime. Precompiled spirv code will be loaded into memory from disk instead.

Current value (from the default): false

From //src/ui/lib/escher/build_args.gni:18

exclude_kernel_service

Whether the VM includes the kernel service in all modes (debug, release, product).

Current value (from the default): false

From //third_party/dart/runtime/runtime_args.gni:88

expat_build_root

Current value (from the default): "//third_party/expat"

From //garnet/lib/magma/gnbuild/magma.gni:12

experimental_wlan_client_mlme

Selects the SoftMAC client implementation to use. Choices: false (default) - C++ Client MLME implementation true - Rust Client MLME implementation This argument is temporary until Rust MLME is ready to be used.

Current value (from the default): false

From //src/connectivity/wlan/lib/mlme/cpp/BUILD.gn:10

extra_manifest_args

Extra args to globally apply to the manifest generation script.

Current value (from the default): []

From //build/images/manifest.gni:22

extra_package_labels

Current value (from the default): []

From //third_party/cobalt/BUILD.gn:10

extra_variants

Additional variant toolchain configs to support. This is just added to known_variants.

Current value (from the default): []

From //build/config/BUILDCONFIG.gn:537

fastboot_product

Current value (from the default): ""

From //build/images/BUILD.gn:50

fidl_write_v1_wireformat

TODO(fxb/41298): This is a temporary change to activate writing the v1 FIDL wire-format selectively. Remove this when all bindings start writing v1 wire-format by default.

Current value (from the default): true

From //build/fidl/wireformat.gni:9

flutter_default_app

Current value (from the default): "flutter_jit_app"

From //topaz/runtime/dart/dart_component.gni:12

flutter_profile

Current value (from the default): true

From //topaz/runtime/dart/dart_component.gni:26

flutter_space_dart

Whether experimental space dart mode is enabled for Flutter applications.

Current value (from the default): false

From //topaz/runtime/dart/dart_component.gni:32

font_catalog_paths

Current value (from the default): ["//prebuilt/third_party/fonts/fuchsia.font_catalog.json"]

From //src/fonts/build/font_args.gni:17

font_pkg_entries

Merged contents of .font_pkgs.json files. Populated in fonts.gni.

Current value (from the default): []

From //src/fonts/build/font_args.gni:32

font_pkgs_paths

Locations of .font_pkgs.json files, which list the locations of font files within the workspace, as well as safe names that are derived from the fonts' file names and can be used to name Fuchsia packages.

Current value (from the default): ["//prebuilt/third_party/fonts/fuchsia.font_pkgs.json"]

From //src/fonts/build/font_args.gni:22

fonts_dir

Directory into which all fonts are checked out from CIPD

Current value (from the default): "//prebuilt/third_party/fonts"

From //src/fonts/build/font_args.gni:12

fuchsia_sdk_root

Consumers of the Fuchsia SDK instantiate templates for various SDK parts at a specific spot within their buildroots. The target name for the specific part is then derived from the part name as specified in the meta.json manifest. Different buildroot instantiate the SDK parts at different locations and then set this variable. GN rules can then prefix this variable name in SDK builds to the name of the SDK part. This flag is meaningless in non-SDK buildroots.

Current value (from the default): ""

From //build/fuchsia/sdk.gni:17

fuchsia_ta_uuids

UUID of TAs to include in the Fuchsia build.

Current value (from the default): []

From //build/images/ta.gni:10

fvm_image_size

The size in bytes of the FVM partition image to create. Normally this is computed to be just large enough to fit the blob and data images. The default value is "", which means to size based on inputs. Specifying a size that is too small will result in build failure.

Current value (from the default): ""

From //build/images/fvm.gni:12

fvm_max_disk_size

The max size of the disk where the FVM is written. This is used for preallocating metadata to determine how much the FVM can expand on disk. Only applies to sparse FVM images. At sparse image construction time, the build fails if the inputs are larger than fvm_max_disk_size. At paving time, the FVM will be sized to the target's disk size up to fvm_max_disk_size. If the size of the disk increases after initial paving, the FVM will resize up to fvm_max_disk_size. During paving, if the target FVM has declared a smaller size than fvm_max_disk_size, the FVM is reinitialized to the larger size. The default value is "" which sets the max disk size to the size of the disk at pave/format time.

Current value (from the default): ""

From //build/images/fvm.gni:25

fvm_slice_size

The size of the FVM partition images “slice size”. The FVM slice size is a minimum size of a particular chunk of a partition that is stored within FVM. A very small slice size may lead to decreased throughput. A very large slice size may lead to wasted space. The selected default size of 8mb is selected for conservation of space, rather than performance.

Current value (from the default): "8388608"

From //build/images/fvm.gni:32

glm_build_root

Current value (from the default): "//third_party/glm"

From //garnet/lib/magma/gnbuild/magma.gni:14

go_vet_enabled

go_vet_enabled [bool] if false, go vet invocations are disabled for all builds.

Current value (from the default): false

From //build/go/go_build.gni:21

gocache_dir

gocache_dir Directory GOCACHE environment variable will be set to. This directory will have build and test results cached, and is safe to be written to concurrently. If overridden, this directory must be a full path.

Current value (from the default): "/b/s/w/ir/k/root_build_dir/host_arm64/.gocache"

From //build/go/go_build.gni:17

goma_dir

Directory containing the Goma source code. This can be a GN source-absolute path (“//...”) or a system absolute path.

Current value (from the default): "/home/swarming/goma"

From //build/toolchain/goma.gni:13

graphics_compute_generate_debug_shaders

Set to true in your args.gn file to generate pre-processed and auto-formatted shaders under the “debug” sub-directory of HotSort and Spinel target generation output directories.

These are never used, but can be reviewed manually to verify the impact of configuration parameters, or when modifying a compute shader.

Example results:

out/default/ gen/src/graphics/lib/compute/ hotsort/targets/hs_amd_gcn3_u64/ comp/ hs_transpose.comp -> unpreprocessed shader debug/ hs_transpose.glsl -> preprocessed shader

Current value (from the default): true

From //src/graphics/lib/compute/gn/glsl_shader_rules.gni:28

graphics_compute_skip_spirv_opt

At times we may want to compare the performance of unoptimized vs. optimized shaders. On desktop platforms, use of spirv-opt doesn't appear to provide major performance improvements but it significantly reduces the size of the SPIR-V modules.

Disabling the spirv-opt pass may also be useful in identifying and attributing code generation bugs.

Current value (from the default): true

From //src/graphics/lib/compute/gn/glsl_shader_rules.gni:38

graphics_compute_verbose_compile

The glslangValidator compiler is noisy by default. A cleanly compiling shader still prints out its filename.

This negatively impacts the GN build.

For this reason, we silence the compiler with the “-s” option but unfortunately this also disables all error reporting.

Set to true to see detailed error reporting.

Current value (from the default): false

From //src/graphics/lib/compute/gn/glsl_shader_rules.gni:50

host_byteorder

Current value (from the default): "undefined"

From //build/config/host_byteorder.gni:7

host_cpu

Current value (from the default): "x64"

host_os

Current value (from the default): "linux"

host_tools_dir

This is the directory where host tools intended for manual use by developers get installed. It‘s something a developer might put into their shell’s $PATH. Host tools that are just needed as part of the build do not get copied here. This directory is only for things that are generally useful for testing or debugging or whatnot outside of the GN build itself. These are only installed by an explicit install_host_tools() rule (see //build/host.gni).

Current value (from the default): "//root_build_dir/host-tools"

From //build/host.gni:13

icu_use_data_file

Tells icu to load an external data file rather than rely on the icudata being linked directly into the binary.

Current value (from the default): true

From //third_party/icu/config.gni:8

include_devmgr_config_in_vbmeta

If true, /config/devmgr config will be included into a vbmeta image instead of bootfs.

Current value (from the default): false

From //build/images/vbmeta.gni:14

include_internal_fonts

Set to true to include internal fonts in the build.

Current value (from the default): false

From //src/fonts/build/font_args.gni:7

include_zxdb_large_tests

Normally these tests are not built and run because they require large amounts of optional data be downloaded. Set this to true to enable the build for the zxdb_large_tests. See symbols/test_data/README.md for how to download the data required for this test.

Current value (from the default): false

From //src/developer/debug/zxdb/BUILD.gn:13

is_debug

Debug build.

Current value (from the default): true

From //build/config/BUILDCONFIG.gn:25

kernel_cmdline_args

List of kernel command line arguments to bake into the boot image. See also //docs/reference/kernel/kernel_cmdline.md and devmgr_config.

Current value for target_cpu = "arm64": ["kernel.enable-debugging-syscalls=true", "netsvc.all-features=true", "netsvc.disable=false", "kernel.oom.behavior=reboot"]

From //products/core.gni:10

Overridden from the default: []

From //build/images/BUILD.gn:512

Current value for target_cpu = "x64": ["kernel.enable-debugging-syscalls=true", "netsvc.all-features=true", "netsvc.disable=false", "kernel.oom.behavior=reboot"]

From //products/core.gni:10

Overridden from the default: []

From //build/images/BUILD.gn:512

kernel_cmdline_files

Files containing additional kernel command line arguments to bake into the boot image. The contents of these files (in order) come after any arguments directly in kernel_cmdline_args. These can be GN // source pathnames or absolute system pathnames.

Current value (from the default): []

From //build/images/BUILD.gn:518

known_variants

List of variants that will form the basis for variant toolchains. To make use of a variant, set select_variant.

Normally this is not set as a build argument, but it serves to document the available set of variants. See also universal_variants. Only set this to remove all the default variants here. To add more, set extra_variants instead.

Each element of the list is one variant, which is a scope defining:

configs (optional) [list of labels] Each label names a config that will be automatically used by every target built in this variant. For each config ${label}, there must also be a target ${label}_deps, which each target built in this variant will automatically depend on. The variant() template is the recommended way to define a config and its _deps target at the same time.

remove_common_configs (optional) remove_shared_configs (optional) [list of labels] This list will be removed (with -=) from the default_common_binary_configs list (or the default_shared_library_configs list, respectively) after all other defaults (and this variant's configs) have been added.

deps (optional) [list of labels] Added to the deps of every target linked in this variant (as well as the automatic ${label}_deps for each label in configs).

name (required if configs is omitted) [string] Name of the variant as used in select_variant elements' variant fields. It's a good idea to make it something concise and meaningful when seen as e.g. part of a directory name under $root_build_dir. If name is omitted, configs must be nonempty and the simple names (not the full label, just the part after all /s and :s) of these configs will be used in toolchain names (each prefixed by a “-”), so the list of config names forming each variant must be unique among the lists in known_variants + extra_variants.

toolchain_args (optional) [scope] Each variable defined in this scope overrides a build argument in the toolchain context of this variant.

host_only (optional) target_only (optional) [scope] This scope can contain any of the fields above. These values are used only for host or target, respectively. Any fields included here should not also be in the outer scope.

Current value (from the default):

[{
  configs = ["//build/config/lto"]
}, {
  configs = ["//build/config/lto:thinlto"]
}, {
  configs = ["//build/config/profile"]
}, {
  configs = ["//build/config/scudo"]
}, {
  configs = ["//build/config/sanitizers:ubsan"]
}, {
  configs = ["//build/config/sanitizers:ubsan", "//build/config/sanitizers:sancov"]
}, {
  configs = ["//build/config/sanitizers:asan"]
  host_only = {
  remove_shared_configs = ["//build/config:symbol_no_undefined"]
}
  toolchain_args = {
  use_scudo = false
}
}, {
  configs = ["//build/config/sanitizers:asan", "//build/config/sanitizers:ubsan"]
  host_only = {
  remove_shared_configs = ["//build/config:symbol_no_undefined"]
}
  toolchain_args = {
  use_scudo = false
}
}, {
  configs = ["//build/config/sanitizers:asan", "//build/config/sanitizers:sancov"]
  host_only = {
  remove_shared_configs = ["//build/config:symbol_no_undefined"]
}
  toolchain_args = {
  use_scudo = false
}
}, {
  configs = ["//build/config/sanitizers:asan"]
  host_only = {
  remove_shared_configs = ["//build/config:symbol_no_undefined"]
}
  name = "asan_no_detect_leaks"
  toolchain_args = {
  asan_default_options = "detect_leaks=0"
  use_scudo = false
}
}, {
  configs = ["//build/config/sanitizers:asan", "//build/config/sanitizers:fuzzer"]
  host_only = {
  remove_shared_configs = ["//build/config:symbol_no_undefined"]
}
  remove_shared_configs = ["//build/config:symbol_no_undefined"]
  toolchain_args = {
  asan_default_options = "alloc_dealloc_mismatch=0"
  use_scudo = false
}
}, {
  configs = ["//build/config/sanitizers:ubsan", "//build/config/sanitizers:fuzzer"]
  remove_shared_configs = ["//build/config:symbol_no_undefined"]
}]

From //build/config/BUILDCONFIG.gn:468

launch_basemgr_on_boot

Indicates whether to include basemgr.cmx in the boot sequence for the product image.

Current value (from the default): true

From //src/modular/build/modular_config/modular_config.gni:11

linux_guest_extras_path

Current value (from the default): ""

From //src/virtualization/packages/linux_guest/BUILD.gn:12

linux_runner_extras_tests

If true, adds additional testonly content to extras.img, which will be built and mounted inside the container at /mnt/chromeos.

Current value (from the default): false

From //src/virtualization/packages/biscotti_guest/linux_runner/BUILD.gn:25

linux_runner_gateway

Current value (from the default): "10.0.0.1"

From //src/virtualization/packages/biscotti_guest/linux_runner/BUILD.gn:20

linux_runner_ip

Default values for the guest network configuration.

These are currently hard-coded to match what is setup in the virtio-net device.

See //src/virtualization/bin/vmm/device/virtio_net.cc for more details.

Current value (from the default): "10.0.0.2"

From //src/virtualization/packages/biscotti_guest/linux_runner/BUILD.gn:19

linux_runner_netmask

Current value (from the default): "255.255.255.0"

From //src/virtualization/packages/biscotti_guest/linux_runner/BUILD.gn:21

linux_runner_volatile_block

If true, all block devices that would normally load as READ_WRITE will be loaded as VOLATILE_WRITE. This is useful when working on changes to the linux kernel as crashes and panics can sometimes corrupt the images.

Current value (from the default): false

From //src/virtualization/packages/biscotti_guest/linux_runner/BUILD.gn:30

local_bench

Used to enable local benchmarking/fine-tuning when running benchmarks in fx shell. Pass --args=local_bench='true' to fx set in order to enable it.

Current value (from the default): false

From //src/developer/fuchsia-criterion/BUILD.gn:14

log_startup_sleep

Current value (from the default): "30000"

From //garnet/bin/log_listener/BUILD.gn:15

magma_build_root

Current value (from the default): "//garnet/lib/magma"

From //garnet/lib/magma/gnbuild/magma.gni:11

magma_enable_developer_build

Enable this to have the msd include a suite of tests and invoke them automatically when the driver starts.

Current value (from the default): false

From //garnet/lib/magma/gnbuild/magma.gni:24

magma_enable_tracing

Enable this to include fuchsia tracing capability

Current value (from the default): true

From //garnet/lib/magma/gnbuild/magma.gni:20

magma_python_path

Current value (from the default): "/b/s/w/ir/k/third_party/mako"

From //garnet/lib/magma/gnbuild/magma.gni:17

max_blob_contents_size

Maximum allowable contents for the /blob in a release mode build. Zero means no limit. contents_size refers to contents stored within the filesystem (regardless of how they are stored).

Current value (from the default): "0"

From //build/images/filesystem_limits.gni:10

max_blob_image_size

Maximum allowable image_size for /blob in a release mode build. Zero means no limit. image_size refers to the total image size, including both contents and metadata.

Current value (from the default): "0"

From //build/images/filesystem_limits.gni:16

max_data_contents_size

Maximum allowable contents_size for /data in a release mode build. Zero means no limit. contents_size refers to contents stored within the filesystem (regardless of how they are stored).

Current value (from the default): "0"

From //build/images/filesystem_limits.gni:22

max_data_image_size

Maximum allowable image_size for /data in a release mode build. Zero means no limit. image_size refers to the total image size, including both contents and metadata.

Current value (from the default): "0"

From //build/images/filesystem_limits.gni:28

max_fuchsia_zbi_size

Maximum allowable size for fuchsia.zbi

Current value for target_cpu = "arm64": "16777216"

From //boards/arm64.gni:15

Overridden from the default: "0"

From //build/images/filesystem_limits.gni:31

Current value for target_cpu = "x64": "16777216"

From //boards/x64.gni:15

Overridden from the default: "0"

From //build/images/filesystem_limits.gni:31

max_fvm_size

Maximum allowable size for the FVM in a release mode build Zero means no limit

Current value (from the default): "0"

From //build/images/max_fvm_size.gni:8

max_log_disk_usage

Controls how many bytes of space on disk are used to persist device logs. Should be a string value that only contains digits.

Current value (from the default): "0"

From //garnet/bin/log_listener/BUILD.gn:14

max_zedboot_zbi_size

Maximum allowable size for zedboot.zbi

Current value for target_cpu = "arm64": "16777216"

From //boards/arm64.gni:16

Overridden from the default: "0"

From //build/images/filesystem_limits.gni:34

Current value for target_cpu = "x64": "16777216"

From //boards/x64.gni:16

Overridden from the default: "0"

From //build/images/filesystem_limits.gni:34

meta_package_labels

A list of labels for meta packages to be included in the monolith.

Current value for target_cpu = "arm64": ["//build/images:config-data", "//build/images:shell-commands", "//src/sys/component_index:component_index"]

From //products/core.gni:14

Overridden from the default: []

From //build/images/BUILD.gn:39

Current value for target_cpu = "x64": ["//build/images:config-data", "//build/images:shell-commands", "//src/sys/component_index:component_index"]

From //products/core.gni:14

Overridden from the default: []

From //build/images/BUILD.gn:39

minfs_maximum_bytes

Current value (from the default): ""

From //build/images/fvm.gni:67

minfs_minimum_data_bytes

Current value (from the default): ""

From //build/images/fvm.gni:53

minfs_minimum_inodes

Current value (from the default): ""

From //build/images/fvm.gni:42

msd_arm_enable_all_cores

Enable all 8 cores, which is faster but emits more heat.

Current value (from the default): true

From //garnet/drivers/gpu/msd-arm-mali/src/BUILD.gn:9

msd_arm_enable_cache_coherency

With this flag set the system tries to use cache coherent memory if the GPU supports it.

Current value (from the default): true

From //garnet/drivers/gpu/msd-arm-mali/src/BUILD.gn:13

msd_arm_enable_protected_debug_swap_mode

In protected mode, faults don‘t return as much information so they’re much harder to debug. To work around that, add a mode where protected atoms are executed in non-protected mode and vice-versa.

NOTE: The memory security ranges should also be set (in TrustZone) to the opposite of normal, so that non-protected mode accesses can only access protected memory and vice versa. Also, growable memory faults won't work in this mode, so larger portions of growable memory should precommitted (which is not done by default).

Current value (from the default): false

From //garnet/drivers/gpu/msd-arm-mali/src/BUILD.gn:23

msd_intel_gen_build_root

Current value (from the default): "//garnet/drivers/gpu/msd-intel-gen"

From //garnet/lib/magma/gnbuild/magma.gni:13

netcfg_autostart

Current value (from the default): true

From //src/connectivity/network/netcfg/BUILD.gn:12

omaha_app_id

Default app id will always return no update.

Current value (from the default): "fuchsia-test:no-update"

From //src/sys/pkg/bin/omaha-client/BUILD.gn:105

output_breakpad_syms

Sets if we should output breakpad symbols for Fuchsia binaries.

Current value (from the default): false

From //build/config/BUILDCONFIG.gn:28

persist_logs

Current value (from the default): true

From //build/persist_logs.gni:13

pre_erase_flash

Current value (from the default): false

From //build/images/BUILD.gn:51

prebuilt_dart_sdk

Directory containing prebuilt Dart SDK. This must have in its bin/ subdirectory gen_snapshot.OS-CPU binaries. Set to empty for a local build.

Current value (from the default): "//prebuilt/third_party/dart/linux-x64"

From //build/dart/dart.gni:9

prebuilt_libvulkan_arm_path

Current value (from the default): ""

From //garnet/lib/magma/gnbuild/magma.gni:26

prebuilt_libvulkan_goldfish_path

Current value (from the default): "//prebuilt/third_party/libvulkan_goldfish/arm64"

From //garnet/lib/goldfish-vulkan/gnbuild/BUILD.gn:10

prebuilt_libvulkan_img_path

The path to a prebuilt libvulkan.so for an IMG GPU.

Current value (from the default): ""

From //garnet/lib/magma/gnbuild/magma.gni:29

prototype_account_transfer

Whether or not prototype account transfer is enabled. NOTE: This is not secure and should NOT be enabled for any products! This is only for use during local development.

Current value (from the default): false

From //src/identity/bin/account_manager/BUILD.gn:12

rust_cap_lints

Sets whether Rust compiler warnings cause errors or not. “deny” will make all warnings into errors, “warn” presents them as warnings, while “allow” will ignore warnings

Current value (from the default): "deny"

From //build/rust/config.gni:28

rust_lto

Sets the default LTO type for rustc bulids.

Current value (from the default): ""

From //build/rust/config.gni:20

rust_override_lto

Overrides the LTO setting for all Rust builds, regardless of debug/release flags or the with_lto arg to the rustc_ templates. Valid values are “none”, “thin”, and “fat”.

Current value (from the default): ""

From //build/rust/config.gni:38

rust_override_opt

Overrides the optimization level for all Rust builds, regardless of debug/release flags or the force_opt arg to the rustc_ templates. Valid values are 0-3, o, and z.

Current value (from the default): ""

From //build/rust/config.gni:33

rust_toolchain_triple_suffix

Sets the fuchsia toolchain target triple suffix (after arch)

Current value (from the default): "fuchsia"

From //build/rust/config.gni:23

rustc_prefix

Sets a custom base directory for rustc and cargo. This can be used to test custom Rust toolchains.

Current value (from the default): "//prebuilt/third_party/rust/linux-x64/bin"

From //build/rust/config.gni:17

scenic_display_frame_number

Draws the current frame number in the top-left corner.

Current value (from the default): false

From //src/ui/scenic/lib/gfx/BUILD.gn:12

scenic_enable_vulkan_validation

Include the vulkan validation layers in scenic.

Current value (from the default): true

From //src/ui/scenic/BUILD.gn:102

scenic_ignore_vsync

Current value (from the default): false

From //src/ui/scenic/lib/gfx/BUILD.gn:9

scudo_default_options

Default Scudo options (before the SCUDO_OPTIONS environment variable is read at runtime). NOTE: This affects only components using the scudo variant (see GN build argument select_variant), and does not affect anything when the use_scudo build flag is set instead.

Current value (from the default): ["abort_on_error=1", "QuarantineSizeKb=0", "ThreadLocalQuarantineSizeKb=0", "DeallocationTypeMismatch=false", "DeleteSizeMismatch=false", "allocator_may_return_null=true"]

From //build/config/scudo/scudo.gni:17

sdk_dirs

The directories to search for parts of the SDK.

By default, we search the public directories for the various layers. In the future, we'll search a pre-built SDK as well.

Current value (from the default): ["//garnet/public", "//peridot/public", "//topaz/public"]

From //build/config/fuchsia/sdk.gni:10

sdk_id

Identifier for the Core SDK.

Current value (from the default): ""

From //sdk/config.gni:7

select_variant

List of “selectors” to request variant builds of certain targets. Each selector specifies matching criteria and a chosen variant. The first selector in the list to match a given target determines which variant is used for that target.

Each selector is either a string or a scope. A shortcut selector is a string; it gets expanded to a full selector. A full selector is a scope, described below.

A string selector can match a name in select_variant_shortcuts. If it‘s not a specific shortcut listed there, then it can be the name of any variant described in known_variants and universal_variants (and combinations thereof). A selector that’s a simple variant name selects for every binary built in the target toolchain: { host=false variant=selector }.

If a string selector contains a slash, then it‘s "shortcut/filename" and selects only the binary in the target toolchain whose output_name matches "filename", i.e. it adds output_name=["filename"] to each selector scope that the shortcut’s name alone would yield.

The scope that forms a full selector defines some of these:

variant (required)
    [string or `false`] The variant that applies if this selector
    matches.  This can be `false` to choose no variant, or a string
    that names the variant.  See
    [`known_variants`](#known_variants) and
    [`universal_variants`](#universal_variants).

The rest below are matching criteria. All are optional. The selector matches if and only if all of its criteria match. If none of these is defined, then the selector always matches.

The first selector in the list to match wins and then the rest of the list is ignored. So construct more complex rules by using a “blacklist” selector with variant=false before a catch-all or “whitelist” selector that names a variant.

Each “[strings]” criterion is a list of strings, and the criterion is satisfied if any of the strings matches against the candidate string.

host
    [boolean] If true, the selector matches in the host toolchain.
    If false, the selector matches in the target toolchain.

testonly
    [boolean] If true, the selector matches targets with testonly=true.
    If false, the selector matches in targets without testonly=true.

target_type
    [strings]: `"executable"`, `"loadable_module"`, or `"driver_module"`

output_name
    [strings]: target's `output_name` (default: its `target name`)

label
    [strings]: target's full label with `:` (without toolchain suffix)

name
    [strings]: target's simple name (label after last `/` or `:`)

dir
    [strings]: target's label directory (`//dir` for `//dir:name`).

Current value (from the default): []

From //build/config/BUILDCONFIG.gn:739

select_variant_canonical

This should never be set as a build argument. It exists only to be set in toolchain_args. See //build/toolchain/clang_toolchain.gni for details.

Current value (from the default): []

From //build/config/BUILDCONFIG.gn:744

select_variant_shortcuts

List of short names for commonly-used variant selectors. Normally this is not set as a build argument, but it serves to document the available set of short-cut names for variant selectors. Each element of this list is a scope where .name is the short name and .select_variant is a a list that can be spliced into select_variant.

Current value (from the default):

[{
  name = "host_asan"
  select_variant = [{
  dir = ["//third_party/yasm", "//third_party/vboot_reference", "//garnet/tools/vboot_reference"]
  host = true
  variant = "asan_no_detect_leaks"
}, {
  host = true
  variant = "asan"
}]
}]

From //build/config/BUILDCONFIG.gn:583

signed_image

Current value (from the default): false

From //build/images/BUILD.gn:49

size_checker_input

The input to the size checker. The build system will produce a JSON file to be consumed by the size checker, which will check and prevent integration of subsystems that are over their space allocation. The input consists of the following keys:

asset_ext(string array): a list of extensions that should be considered as assets.

asset_limit(number): maximum size (in bytes) allocated for the assets.

core_limit(number): maximum size (in bytes) allocated for the core system and/or services. This is sort of a “catch all” component that consists of all the area / packages that weren't specified in the components list below.

components(object array): a list of component objects. Each object should contain the following keys:

component(string): name of the component.

src(string array): path of the area / package to be included as part of the component. The path should be relative to the build directory. The target may also be a directory, in which case all blobs under that directory will be taken into account.

limit(number): maximum size (in bytes) allocated for the component.

Example: size_checker_input = { asset_ext = [ “.ttf” ] asset_limit = 10240 core_limit = 10240 components = [ { component = “Foo” src = [ “obj/topaz/runtime/foo_runner” ] limit = 10240 }, { component = “Bar” src = [ “obj/build/images” ] limit = 20480 }, ] }

Current value (from the default): { }

From //tools/size_checker/cmd/BUILD.gn:48

symbol_level

How many symbols to include in the build. This affects the performance of the build since the symbols are large and dealing with them is slow. 2 means regular build with symbols. 1 means minimal symbols, usually enough for backtraces only. Symbols with internal linkage (static functions or those in anonymous namespaces) may not appear when using this level. 0 means no symbols.

Current value (from the default): 2

From //build/config/compiler.gni:13

syzkaller_dir

Used by syz-ci to build with own syz-executor source.

Current value (from the default): "//third_party/syzkaller"

From //src/testing/fuzzing/syzkaller/BUILD.gn:9

ta_dest_suffix

File name suffix of TA images deployed on bootfs. Usually it is “.ta”. The TA image file names are “$ta_uuid$ta_dest_suffix”.

Current value (from the default): ""

From //build/images/ta.gni:21

ta_path

Source absolute path to the prebuilt TA images.

Current value (from the default): ""

From //build/images/ta.gni:7

ta_src_suffix

File name suffix of prebuilt TA images. “.ta.prod” and “.ta.dev” are usually used. The TA image file names are “$ta_uuid$ta_src_suffix”.

Current value (from the default): ""

From //build/images/ta.gni:17

target_cpu

Current value for target_cpu = "arm64": "arm64"

From //boards/arm64.gni:5

Overridden from the default: ""

Current value for target_cpu = "x64": "x64"

From //boards/x64.gni:5

Overridden from the default: ""

target_os

Current value (from the default): ""

target_sysroot

The absolute path of the sysroot that is used with the target toolchain.

Current value (from the default): ""

From //build/config/sysroot.gni:7

termina_disk

The termina disk image.

Defaults to the disk image from CIPD, but can be overridden to use a custom disk for development purposes.

Current value (from the default): "//prebuilt/virtualization/packages/termina_guest/images/arm64/vm_rootfs.img"

From //src/virtualization/packages/termina_guest/BUILD.gn:18

termina_kernel

The termina kernel image.

Defaults to the common linux kernel image from CIPD, but can be overridden to use a custom kernel for development purposes.

Current value (from the default): "//prebuilt/virtualization/packages/linux_guest/images/arm64/Image"

From //src/virtualization/packages/termina_guest/BUILD.gn:12

thinlto_cache_dir

ThinLTO cache directory path.

Current value (from the default): "dartlang/thinlto-cache"

From //build/config/lto/config.gni:16

thinlto_jobs

Number of parallel ThinLTO jobs.

Current value (from the default): 8

From //build/config/lto/config.gni:13

toolchain_manifests

Manifest files describing target libraries from toolchains. Can be either // source paths or absolute system paths.

Current value (from the default): ["/b/s/w/ir/k/prebuilt/third_party/clang/linux-x64/lib/aarch64-fuchsia.manifest"]

From //build/images/manifest.gni:11

toolchain_variant

This should never be set as a build argument. It exists only to be set in toolchain_args. See //build/toolchain/clang_toolchain.gni for details. This variable is a scope giving details about the current toolchain: toolchain_variant.base [label] The “base” toolchain for this variant, often the right thing to use in comparisons, not current_toolchain. This is the toolchain actually referenced directly in GN source code. If the current toolchain is not shlib_toolchain or a variant toolchain, this is the same as current_toolchain. In one of those derivative toolchains, this is the toolchain the GN code probably thought it was in. This is the right thing to use in a test like toolchain_variant.base == target_toolchain, rather rather than comparing against current_toolchain. toolchain_variant.name [string] The name of this variant, as used in variant fields in select_variant clauses. In the base toolchain and its shlib_toolchain, this is "". toolchain_variant.suffix [string] This is “-${toolchain_variant.name}”, "" if name is empty. toolchain_variant.is_pic_default [bool] This is true in shlib_toolchain. The other fields are the variant's effects as defined in known_variants.

Current value (from the default):

{
  base = "//build/toolchain/fuchsia:arm64"
}

From //build/config/BUILDCONFIG.gn:100

universal_variants

Current value (from the default):

[{
  configs = []
  name = "release"
  toolchain_args = {
  is_debug = false
}
}]

From //build/config/BUILDCONFIG.gn:557

universe_package_labels

If you add package labels to this variable, the packages will be included in the ‘universe’ package set, which represents all software that is produced that is to be published to a package repository or to the SDK by the build. The build system ensures that the universe package set includes the base and cache package sets, which means you do not need to redundantly include those labels in this variable.

Current value for target_cpu = "arm64": ["//garnet/tools/vboot_reference:cgpt_host", "//garnet/tools/vboot_reference:futility_host", "//bundles:tools"]

From //products/core.gni:83

Overridden from the default: []

From //BUILD.gn:35

Current value for target_cpu = "x64": ["//garnet/tools/vboot_reference:cgpt_host", "//garnet/tools/vboot_reference:futility_host", "//bundles:tools"]

From //products/core.gni:83

Overridden from the default: []

From //BUILD.gn:35

unpack_debug_archives

To ensure that everything can be built without debug symbols present we gate weather or not these are consumed on a build argument. When set, unpack_debug_archives creates an additional build step that unpacks debug archives in tar.bzip2 format into the .build-id directory

Current value (from the default): false

From //build/packages/prebuilt_package.gni:11

update_kernels

(deprecated) List of kernel images to include in the update (OTA) package. If no list is provided, all built kernels are included. The names in the list are strings that must match the filename to be included in the update package.

Current value (from the default): []

From //build/images/BUILD.gn:530

use_ccache

Set to true to enable compiling with ccache

Current value (from the default): false

From //build/toolchain/ccache.gni:9

use_goma

Set to true to enable distributed compilation using Goma.

Current value (from the default): false

From //build/toolchain/goma.gni:9

use_lto

Use link time optimization (LTO).

Current value (from the default): false

From //build/config/lto/config.gni:7

use_mock_magma

Current value (from the default): false

From //third_party/mesa/src/intel/vulkan/BUILD.gn:25

use_nnbd

Whether to use the NNBD fork of the SDK core libraries. TODO(#38701): Remove this when the fork has been merged back in.

Current value (from the default): false

From //third_party/dart/sdk_args.gni:4

use_prebuilt_dart_sdk

Whether to use the prebuilt Dart SDK for everything. When setting this to false, the preubilt Dart SDK will not be used in situations where the version of the SDK matters, but may still be used as an optimization where the version does not matter.

Current value (from the default): true

From //build/dart/dart.gni:15

use_prebuilt_ffmpeg

Use a prebuilt ffmpeg binary rather than building it locally. See //src/media/lib/ffmpeg/README.md for details. This is ignored when building in variant builds for which there is no prebuilt. In that case, ffmpeg is always built from source so as to be built with the selected variant's config. When this is false (either explicitly or in a variant build) then //third_party/ffmpeg must be in the source tree, which requires: jiri import -name integration third_party/ffmpeg https://fuchsia.googlesource.com/integration

Current value (from the default): true

From //src/media/lib/ffmpeg/BUILD.gn:14

use_scudo

TODO(davemoore): Remove this entire mechanism once standalone scudo is the default (DNO-442) Enable the Scudo memory allocator.

Current value (from the default): false

From //build/config/scudo/scudo.gni:10

use_thinlto

Use ThinLTO variant of LTO if use_lto = true.

Current value (from the default): true

From //build/config/lto/config.gni:10

use_vbmeta

If true, then a vbmeta image will be generated for provided ZBI and the paving script will pave vbmeta images to the target device.

Current value (from the default): false

From //build/images/vbmeta.gni:10

use_vboot

Use vboot images

Current value (from the default): false

From //build/images/boot.gni:11

using_fuchsia_sdk

Only set in buildroots where targets configure themselves for use with the Fuchsia SDK

Current value (from the default): false

From //build/fuchsia/sdk.gni:8

vbmeta_a_partition

Current value (from the default): ""

From //build/images/BUILD.gn:45

vbmeta_b_partition

Current value (from the default): ""

From //build/images/BUILD.gn:46

vbmeta_r_partition

Current value (from the default): ""

From //build/images/BUILD.gn:47

vendor_linting

Whether libraries under //vendor should be linted.

Current value (from the default): false

From //build/fidl/fidl_library.gni:13

virtmagma_debug

Enable verbose logging in virtmagma-related code

Current value (from the default): false

From //garnet/lib/magma/include/virtio/virtmagma_debug.gni:7

vulkan_sdk

Current value (from the default): ""

From //src/graphics/examples/vkprimer/BUILD.gn:50

warn_on_sdk_changes

Whether to only warn when an SDK has been modified. If false, any unacknowledged SDK change will cause a build failure.

Current value (from the default): false

From //build/sdk/config.gni:11

wlancfg_config_type

Selects the wlan configuration type to use. Choices: “client” - client mode “ap” - access point mode "" (empty string) - no configuration

Current value (from the default): "client"

From //src/connectivity/wlan/wlancfg/BUILD.gn:16

zbi_compression

Compression setting for ZBI “storage” items. This can be either “lz4f” or “zstd”, optionally followed by “.LEVEL” where LEVEL can be an integer or “max”.

Current value (from the default): "zstd"

From //build/config/fuchsia/zbi.gni:11

zedboot_cmdline_args

List of kernel command line arguments to bake into the Zedboot image. See //docs/zircon/kernel_cmdline.md and zedboot_devmgr_config.

Current value (from the default): []

From //build/images/zedboot/zedboot_args.gni:9

zedboot_cmdline_files

Files containing additional kernel command line arguments to bake into the Zedboot image. The contents of these files (in order) come after any arguments directly in zedboot_cmdline_args. These can be GN // source pathnames or absolute system pathnames.

Current value (from the default): []

From //build/images/zedboot/zedboot_args.gni:15

zedboot_devmgr_config

List of arguments to populate /boot/config/devmgr in the Zedboot image.

Current value (from the default): []

From //build/images/zedboot/zedboot_args.gni:18

zedboot_ta_uuids

UUID of TAs to include in the Zedboot build.

Current value (from the default): []

From //build/images/ta.gni:13

zircon_a_partition

arguments to fx flash script

Current value (from the default): ""

From //build/images/BUILD.gn:42

zircon_args

Zircon GN build arguments. The default passes through GOMA/ccache settings and select_variant shorthand selectors. Only set this if you want to wipe out all the defaults that propagate from Fuchsia GN to Zircon GN. The default value folds in zircon_extra_args, so usually it's better to just set zircon_extra_args and leave zircon_args alone. Any individual Zircon build argument set in zircon_extra_args will silently clobber the default value shown here.

Current value (from the default):

{
  default_deps = ["//:legacy-arm64", "//:legacy_unification-arm64"]
  enable_netsvc_debugging_features = false
  goma_dir = "/home/swarming/goma"
  use_ccache = false
  use_goma = false
  variants = []
  zbi_compression = "zstd"
}

From //BUILD.gn:84

zircon_asserts

Current value (from the default): true

From //build/config/fuchsia/BUILD.gn:223

zircon_b_partition

Current value (from the default): ""

From //build/images/BUILD.gn:43

zircon_build_root

Current value (from the default): "//zircon"

From //garnet/lib/magma/gnbuild/magma.gni:15

zircon_compdb_filter

Compilation database filter. Gets passed to --export-compile-commands=.

Current value (from the default): "legacy-arm64"

From //BUILD.gn:63

zircon_enable_netsvc_debugging_features

Whether to include various features (non-shipping, insecure, etc.) in the netsvc build.

Current value for target_cpu = "arm64": false

From //products/core.gni:12

Overridden from the default: false

From //BUILD.gn:56

Current value for target_cpu = "x64": false

From //products/core.gni:12

Overridden from the default: false

From //BUILD.gn:56

zircon_extra_args

Zircon GN build arguments. This is included in the default value of zircon_args so you can set this to add things there without wiping out the defaults. When you set zircon_args directly, then this has no effect at all. Arguments you set here override any arguments in the default zircon_args. There is no way to append to a value from the defaults. Note that for just setting simple (string-only) values in Zircon GN‘s variants, the default zircon_args uses a variants value derived from select_variant so for simple cases there is no need to explicitly set Zircon’s variants here.

Current value (from the default): { }

From //BUILD.gn:48

zircon_extra_deps

Additional Zircon GN labels to include in the Zircon build.

Current value (from the default): []

From //BUILD.gn:52

zircon_r_partition

Current value (from the default): ""

From //build/images/BUILD.gn:44

zircon_tracelog

Where to emit a tracelog from Zircon's GN run. No trace will be produced if given the empty string. Path can be source-absolute or system-absolute.

Current value (from the default): ""

From //BUILD.gn:60

zvb_partition_name

Partition name from where image will be verified

Current value (from the default): "zircon"

From //build/images/vbmeta.gni:32

zxcrypt_key_source

This argument specifies from where the system should obtain the zxcrypt master key to the system data partition.

This value be reified as /boot/config/zxcrypt in both the zircon boot image and the zedboot boot image, for consumption by fshost and the paver, respectively.

Acceptable values are:

  • “null”: the device should use an all-0's master key, as we lack support for any secure on-device storage.
  • “tee”: the device is required to have a Trusted Execution Environment (TEE) which includes the “keysafe” Trusted Application (associated with the KMS service). The zxcrypt master key should be derived from a per-device key accessible only to trusted apps running in the TEE.
  • “tee-opportunistic”: the device will attempt to use keys from the TEE if available, but will fall back to using the null key if the key from the TEE does not work, or if the TEE is not functional on this device.
  • “tee-transitional”: the device will require the use of a key from the TEE for new volume creation, but will continue to try both a TEE-sourced key and the null key when unsealing volumes.

In the future, we may consider adding support for TPMs, or additional logic to explicitly support other fallback behavior.

Current value (from the default): "null"

From //build/images/zxcrypt.gni:29

target_cpu = "arm64"

amlogic_decoder_firmware_path

Path to the amlogic decoder firmware file. Overrides the default in the build.

Current value (from the default): ""

From //garnet/drivers/video/amlogic-decoder/BUILD.gn:14

amlogic_decoder_tests

Current value (from the default): false

From //garnet/drivers/video/amlogic-decoder/BUILD.gn:11

arm_float_abi

The ARM floating point mode. This is either the string “hard”, “soft”, or “softfp”. An empty string means to use the default one for the arm_version.

Current value (from the default): ""

From //build/config/arm.gni:20

arm_optionally_use_neon

Whether to enable optional NEON code paths.

Current value (from the default): false

From //build/config/arm.gni:31

arm_tune

The ARM variant-specific tuning mode. This will be a string like “armv6” or “cortex-a15”. An empty string means to use the default for the arm_version.

Current value (from the default): ""

From //build/config/arm.gni:25

arm_use_neon

Whether to use the neon FPU instruction set or not.

Current value (from the default): true

From //build/config/arm.gni:28

arm_version

Current value (from the default): 8

From //build/config/arm.gni:12