.gn - chromium/src - Git at Google

 # This file is used by the GN meta build system to find the root of the source
 # tree and to set startup options. For documentation on the values set in this
 # file, run "gn help dotfile" at the command line.

 import("//build/dotfile_settings.gni")
 import("//third_party/angle/dotfile_settings.gni")

 # The location of the build configuration file.
 buildconfig = "//build/config/BUILDCONFIG.gn"

 # The python interpreter to use by default. On Windows, this will look
 # for python3.exe and python3.bat.
 script_executable = "python3"

 # These arguments override the default values for items in a declare_args
 # block. "gn args" in turn can override these.
 #
 # In general the value for a build arg in the declare_args block should be the
 # default. In some cases, a DEPS-ed in project will want different defaults for
 # being built as part of Chrome vs. being built standalone. In this case, the
 # Chrome defaults should go here. There should be no overrides here for
 # values declared in the main Chrome repository.
 #
 # Important note for defining defaults: This file is executed before the
 # BUILDCONFIG.gn file. That file sets up the global variables like "is_ios".
 # This means that the default_args can not depend on the platform,
 # architecture, or other build parameters. If you really need that, the other
 # repo should define a flag that toggles on a behavior that implements the
 # additional logic required by Chrome to set the variables.
 default_args = {
   # TODO(brettw) bug 684096: Chrome on iOS does not build v8, so "gn gen" prints
   # a warning that "Build argument has no effect". When adding a v8 variable, it
   # also needs to be defined to src/ios/BUILD.gn (respectively removed from both
   # location when it is removed).

   v8_enable_gdbjit = false
   v8_imminent_deprecation_warnings = false

   # Don't include webrtc's builtin task queue implementation.
   rtc_link_task_queue_impl = false

   # When building with Chromium, `webrtc::Location` is replaced by
   # `base::Location`. Since WebRTC doesn't use `public_deps` (webrtc:8603), it
   # would fail to propagate the dependency internally. Instead WebRTC let its
   # embedders to define it globally for all of its targets.
   rtc_common_public_deps = [ "//base" ]

   # Don't include the iLBC audio codec.
   # TODO(bugs.webrtc.org/8396): Once WebRTC gets rid of its internal
   # deps on codecs, we can remove this.
   rtc_include_ilbc = false

   # Changes some setup for the Crashpad build to set them to build against
   # Chromium's zlib, base, etc.
   crashpad_dependencies = "chromium"

   # Override ANGLE's Vulkan dependencies.
   angle_vulkan_headers_dir = "//third_party/vulkan-deps/vulkan-headers/src"
   angle_vulkan_loader_dir = "//third_party/vulkan-deps/vulkan-loader/src"
   angle_vulkan_tools_dir = "//third_party/vulkan-deps/vulkan-tools/src"
   angle_vulkan_validation_layers_dir =
       "//third_party/vulkan-deps/vulkan-validation-layers/src"

   # Overwrite default args declared in the Fuchsia sdk
   fuchsia_sdk_readelf_exec =
       "//third_party/llvm-build/Release+Asserts/bin/llvm-readelf"

   # Overwrite default args declared in the pdfium library
   pdf_use_partition_alloc_new_location = true

   devtools_visibility = [ "*" ]
 }

 # These are the targets to skip header checking by default. The files in targets
 # matching these patterns (see "gn help label_pattern" for format) will not have
 # their includes checked for proper dependencies when you run either
 # "gn check" or "gn gen --check".
 no_check_targets = [
   # //v8, https://crbug.com/v8/7330
   "//v8/src/inspector:inspector",  # 20 errors
   "//v8/test/cctest:cctest_sources",  # 15 errors
   "//v8/test/unittests:inspector_unittests_sources",  # 2 errors
   "//v8:cppgc_base",  # 1 error
   "//v8:v8_internal_headers",  # 11 errors
   "//v8:v8_libplatform",  # 2 errors
 ]

 # These are the list of GN files that run exec_script. This whitelist exists
 # to force additional review for new uses of exec_script, which is strongly
 # discouraged.
 #
 # PLEASE READ
 #
 # You should almost never need to add new exec_script calls. exec_script is
 # slow, especially on Windows, and can cause confusing effects. Although
 # individually each call isn't slow or necessarily very confusing, at the scale
 # of our repo things get out of hand quickly. By strongly pushing back on all
 # additions, we keep the build fast and clean. If you think you need to add a
 # new call, please consider:
 #
 # - Do not use a script to check for the existence of a file or directory to
 #   enable a different mode. Instead, use GN build args to enable or disable
 #   functionality and set options. An example is checking for a file in the
 #   src-internal repo to see if the corresponding src-internal feature should
 #   be enabled. There are several things that can go wrong with this:
 #
 #    - It's mysterious what causes some things to happen. Although in many cases
 #      such behavior can be conveniently automatic, GN optimizes for explicit
 #      and obvious behavior so people can more easily diagnose problems.
 #
 #    - The user can't enable a mode for one build and not another. With GN build
 #      args, the user can choose the exact configuration of multiple builds
 #      using one checkout. But implicitly basing flags on the state of the
 #      checkout, this functionality is broken.
 #
 #    - It's easy to get stale files. If for example the user edits the gclient
 #      to stop checking out src-internal (or any other optional thing), it's
 #      easy to end up with stale files still mysteriously triggering build
 #      conditions that are no longer appropriate (yes, this happens in real
 #      life).
 #
 # - Do not use a script to iterate files in a directory (glob):
 #
 #    - This has the same "stale file" problem as the above discussion. Various
 #      operations can leave untracked files in the source tree which can cause
 #      surprising effects.
 #
 #    - It becomes impossible to use "git grep" to find where a certain file is
 #      referenced. This operation is very common and people really do get
 #      confused when things aren't listed.
 #
 #    - It's easy to screw up. One common case is a build-time script that packs
 #      up a directory. The author notices that the script isn't re-run when the
 #      directory is updated, so adds a glob so all the files are listed as
 #      inputs. This seems to work great... until a file is deleted. When a
 #      file is deleted, all the inputs the glob lists will still be up to date
 #      and no command-lines will have been changed. The action will not be
 #      re-run and the build will be broken. It is possible to get this correct
 #      using glob, and it's possible to mess it up without glob, but globs make
 #      this situation much easier to create. if the build always lists the
 #      files and passes them to a script, it will always be correct.

 exec_script_whitelist =
     build_dotfile_settings.exec_script_whitelist +
     angle_dotfile_settings.exec_script_whitelist +
     [
       # Whitelist entries for //build should go into
       # //build/dotfile_settings.gni instead, so that they can be shared
       # with other repos. The entries in this list should be only for files
       # in the Chromium repo outside of //build.
       "//build_overrides/build.gni",

       "//chrome/android/webapk/shell_apk/prepare_upload_dir/BUILD.gn",
       "//chrome/version.gni",

       # TODO(dgn): Layer violation but breaks the build otherwise, see
       # https://crbug.com/474506.
       "//clank/java/BUILD.gn",
       "//clank/native/BUILD.gn",

       "//google_apis/BUILD.gn",
       "//printing/BUILD.gn",

       "//remoting/host/installer/linux/BUILD.gn",
       "//remoting/remoting_version.gni",
       "//remoting/host/installer/win/generate_clsids.gni",

       "//tools/grit/grit_rule.gni",
       "//tools/gritsettings/BUILD.gn",
     ]
	# This file is used by the GN meta build system to find the root of the source
	# tree and to set startup options. For documentation on the values set in this
	# file, run "gn help dotfile" at the command line.

	import("//build/dotfile_settings.gni")
	import("//third_party/angle/dotfile_settings.gni")

	# The location of the build configuration file.
	buildconfig = "//build/config/BUILDCONFIG.gn"

	# The python interpreter to use by default. On Windows, this will look
	# for python3.exe and python3.bat.
	script_executable = "python3"

	# These arguments override the default values for items in a declare_args
	# block. "gn args" in turn can override these.
	#
	# In general the value for a build arg in the declare_args block should be the
	# default. In some cases, a DEPS-ed in project will want different defaults for
	# being built as part of Chrome vs. being built standalone. In this case, the
	# Chrome defaults should go here. There should be no overrides here for
	# values declared in the main Chrome repository.
	#
	# Important note for defining defaults: This file is executed before the
	# BUILDCONFIG.gn file. That file sets up the global variables like "is_ios".
	# This means that the default_args can not depend on the platform,
	# architecture, or other build parameters. If you really need that, the other
	# repo should define a flag that toggles on a behavior that implements the
	# additional logic required by Chrome to set the variables.
	default_args = {
	# TODO(brettw) bug 684096: Chrome on iOS does not build v8, so "gn gen" prints
	# a warning that "Build argument has no effect". When adding a v8 variable, it
	# also needs to be defined to src/ios/BUILD.gn (respectively removed from both
	# location when it is removed).

	v8_enable_gdbjit = false
	v8_imminent_deprecation_warnings = false

	# Don't include webrtc's builtin task queue implementation.
	rtc_link_task_queue_impl = false

	# When building with Chromium, `webrtc::Location` is replaced by
	# `base::Location`. Since WebRTC doesn't use `public_deps` (webrtc:8603), it
	# would fail to propagate the dependency internally. Instead WebRTC let its
	# embedders to define it globally for all of its targets.
	rtc_common_public_deps = [ "//base" ]

	# Don't include the iLBC audio codec.
	# TODO(bugs.webrtc.org/8396): Once WebRTC gets rid of its internal
	# deps on codecs, we can remove this.
	rtc_include_ilbc = false

	# Changes some setup for the Crashpad build to set them to build against
	# Chromium's zlib, base, etc.
	crashpad_dependencies = "chromium"

	# Override ANGLE's Vulkan dependencies.
	angle_vulkan_headers_dir = "//third_party/vulkan-deps/vulkan-headers/src"
	angle_vulkan_loader_dir = "//third_party/vulkan-deps/vulkan-loader/src"
	angle_vulkan_tools_dir = "//third_party/vulkan-deps/vulkan-tools/src"
	angle_vulkan_validation_layers_dir =
	"//third_party/vulkan-deps/vulkan-validation-layers/src"

	# Overwrite default args declared in the Fuchsia sdk
	fuchsia_sdk_readelf_exec =
	"//third_party/llvm-build/Release+Asserts/bin/llvm-readelf"

	# Overwrite default args declared in the pdfium library
	pdf_use_partition_alloc_new_location = true

	devtools_visibility = [ "*" ]
	}

	# These are the targets to skip header checking by default. The files in targets
	# matching these patterns (see "gn help label_pattern" for format) will not have
	# their includes checked for proper dependencies when you run either
	# "gn check" or "gn gen --check".
	no_check_targets = [
	# //v8, https://crbug.com/v8/7330
	"//v8/src/inspector:inspector", # 20 errors
	"//v8/test/cctest:cctest_sources", # 15 errors
	"//v8/test/unittests:inspector_unittests_sources", # 2 errors
	"//v8:cppgc_base", # 1 error
	"//v8:v8_internal_headers", # 11 errors
	"//v8:v8_libplatform", # 2 errors
	]

	# These are the list of GN files that run exec_script. This whitelist exists
	# to force additional review for new uses of exec_script, which is strongly
	# discouraged.
	#
	# PLEASE READ
	#
	# You should almost never need to add new exec_script calls. exec_script is
	# slow, especially on Windows, and can cause confusing effects. Although
	# individually each call isn't slow or necessarily very confusing, at the scale
	# of our repo things get out of hand quickly. By strongly pushing back on all
	# additions, we keep the build fast and clean. If you think you need to add a
	# new call, please consider:
	#
	# - Do not use a script to check for the existence of a file or directory to
	# enable a different mode. Instead, use GN build args to enable or disable
	# functionality and set options. An example is checking for a file in the
	# src-internal repo to see if the corresponding src-internal feature should
	# be enabled. There are several things that can go wrong with this:
	#
	# - It's mysterious what causes some things to happen. Although in many cases
	# such behavior can be conveniently automatic, GN optimizes for explicit
	# and obvious behavior so people can more easily diagnose problems.
	#
	# - The user can't enable a mode for one build and not another. With GN build
	# args, the user can choose the exact configuration of multiple builds
	# using one checkout. But implicitly basing flags on the state of the
	# checkout, this functionality is broken.
	#
	# - It's easy to get stale files. If for example the user edits the gclient
	# to stop checking out src-internal (or any other optional thing), it's
	# easy to end up with stale files still mysteriously triggering build
	# conditions that are no longer appropriate (yes, this happens in real
	# life).
	#
	# - Do not use a script to iterate files in a directory (glob):
	#
	# - This has the same "stale file" problem as the above discussion. Various
	# operations can leave untracked files in the source tree which can cause
	# surprising effects.
	#
	# - It becomes impossible to use "git grep" to find where a certain file is
	# referenced. This operation is very common and people really do get
	# confused when things aren't listed.
	#
	# - It's easy to screw up. One common case is a build-time script that packs
	# up a directory. The author notices that the script isn't re-run when the
	# directory is updated, so adds a glob so all the files are listed as
	# inputs. This seems to work great... until a file is deleted. When a
	# file is deleted, all the inputs the glob lists will still be up to date
	# and no command-lines will have been changed. The action will not be
	# re-run and the build will be broken. It is possible to get this correct
	# using glob, and it's possible to mess it up without glob, but globs make
	# this situation much easier to create. if the build always lists the
	# files and passes them to a script, it will always be correct.

	exec_script_whitelist =
	build_dotfile_settings.exec_script_whitelist +
	angle_dotfile_settings.exec_script_whitelist +
	[
	# Whitelist entries for //build should go into
	# //build/dotfile_settings.gni instead, so that they can be shared
	# with other repos. The entries in this list should be only for files
	# in the Chromium repo outside of //build.
	"//build_overrides/build.gni",

	"//chrome/android/webapk/shell_apk/prepare_upload_dir/BUILD.gn",
	"//chrome/version.gni",

	# TODO(dgn): Layer violation but breaks the build otherwise, see
	# https://crbug.com/474506.
	"//clank/java/BUILD.gn",
	"//clank/native/BUILD.gn",

	"//google_apis/BUILD.gn",
	"//printing/BUILD.gn",

	"//remoting/host/installer/linux/BUILD.gn",
	"//remoting/remoting_version.gni",
	"//remoting/host/installer/win/generate_clsids.gni",

	"//tools/grit/grit_rule.gni",
	"//tools/gritsettings/BUILD.gn",
	]