webrtc 常用編譯引數列表
阿新 • • 發佈:2018-12-18
additional_target_cpus Current value (from the default) = [] From //build/config/ios/ios_sdk.gni:58 If non-empty, this list must contain valid cpu architecture, and the final build will be a multi-architecture build (aka fat build) supporting the main $target_cpu architecture and all of $additional_target_cpus. For example to build an application that will run on both arm64 and armv7 devices, you would use the following in args.gn file when running "gn args": target_os = "ios" target_cpu = "arm64" additional_target_cpus = [ "arm" ] You can also pass the value via "--args" parameter for "gn gen" command by using the syntax --args='additional_target_cpus=["arm"] target_cpu="arm64"'. aec_untrusted_delay_for_testing Current value (from the default) = false From //webrtc/modules/audio_processing/BUILD.gn:17 Disables the usual mode where we trust the reported system delay values the AEC receives. The corresponding define is set appropriately in the code, but it can be force-enabled here for testing. allow_posix_link_time_opt Current value (from the default) = false From //build/toolchain/toolchain.gni:17 android_full_debug Current value (from the default) = false From //build/config/compiler/BUILD.gn:42 Normally, Android builds are lightly optimized, even for debug builds, to keep binary size down. Setting this flag to true disables such optimization apm_debug_dump Current value (from the default) = false From //webrtc/webrtc.gni:69 Selects whether debug dumps for the audio processing module should be generated. asan_globals Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:148 Detect overflow/underflow for global objects. Mac: http://crbug.com/352073 auto_profile_path Current value (from the default) = "" From //build/config/compiler/BUILD.gn:97 AFDO (Automatic Feedback Directed Optimizer) is a form of profile-guided optimization that GCC supports. It used by ChromeOS in their official builds. To use it, set auto_profile_path to the path to a file containing the needed gcov profiling data. binutils_path Current value (from the default) = "../../third_party/binutils/Linux_x64/Release/bin" From //build/config/compiler/BUILD.gn:51 build_libsrtp_tests Current value (from the default) = false From //third_party/libsrtp/BUILD.gn:10 Tests may not be appropriate for some build environments, e.g. Windows. Rather than enumerate valid options, we just let clients ask for them. build_with_mozilla Current value (from the default) = false From //webrtc/webrtc.gni:89 Enable to use the Mozilla internal settings. bundle_pool_depth Current value (from the default) = -1 From //build/toolchain/mac/BUILD.gn:29 Reduce the number of tasks using the copy_bundle_data and compile_xcassets tools as they can cause lots of I/O contention when invoking ninja with a large number of parallel jobs (e.g. when using distributed build like goma). cc_wrapper Current value (from the default) = "" From //build/toolchain/cc_wrapper.gni:36 Set to "ccache", "icecc" or "distcc". Probably doesn't work on windows. chrome_pgo_phase Current value (from the default) = 0 From //build/config/compiler/pgo/pgo.gni:13 Specify the current PGO phase. Here's the different values that can be used: 0 : Means that PGO is turned off. 1 : Used during the PGI (instrumentation) phase. 2 : Used during the PGO (optimization) phase. TODO(sebmarchand): Add support for the PGU (update) phase. clang_base_path Current value (from the default) = "//third_party/llvm-build/Release+Asserts" From //build/config/clang/clang.gni:12 clang_use_chrome_plugins Current value (from the default) = true From //build/config/clang/clang.gni:10 Indicates if the build should use the Chrome-specific plugins for enforcing coding guidelines, etc. Only used when compiling with Clang. clang_version Current value (from the default) = "6.0.0" From //build/toolchain/toolchain.gni:67 Clang compiler version. Clang files are placed at version-dependent paths. concurrent_links Current value (from the default) = -1 From //build/toolchain/concurrent_links.gni:19 Limit the number of concurrent links; 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_cpu Current value (from the default) = "" (Internally set; try `gn help current_cpu`.) current_os Current value (from the default) = "" (Internally set; try `gn help current_os`.) custom_toolchain Current value (from the default) = "" From //build/config/BUILDCONFIG.gn:147 Allows the path to a custom target toolchain to be injected as a single argument, and set as the default toolchain. dcheck_always_on Current value (from the default) = false From //build/config/dcheck_always_on.gni:7 Set to true to enable dcheck in Release builds. disable_libfuzzer Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:95 Helper variable for testing builds with disabled libfuzzer. Not for client use. enable_dsyms Current value (from the default) = false From //build/config/mac/symbols.gni:17 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_full_stack_frames_for_profiling Current value (from the default) = false From //build/config/compiler/BUILD.gn:59 Compile in such a way as to make it possible for the profiler to unwind full stack frames. Setting this flag has a large effect on the performance of the generated code than just setting profiling, but gives the profiler more information to analyze. Requires profiling to be set to true. enable_ios_bitcode Current value (from the default) = false From //build/config/ios/BUILD.gn:23 Enabling this option makes clang compile to an intermediate representation ("bitcode"), and not to native code. This is preferred when including WebRTC in the apps that will be sent to Apple's App Store and mandatory for the apps that run on watchOS or tvOS. The option only works when building with Xcode (use_xcode_clang = true). Mimicking how Xcode handles it, the production builds (is_debug = false) get real bitcode sections added, while the debug builds (is_debug = true) only get bitcode-section "markers" added in them. NOTE: This option is ignored when building versions for the iOS simulator, where a part of libvpx is compiled from the assembly code written using Intel assembly syntax; Yasm / Nasm do not support emitting bitcode parts. That is not a limitation for now as Xcode mandates the presence of bitcode only when building bitcode-enabled projects for real devices (ARM CPUs). enable_iterator_debugging Current value (from the default) = true From //build/config/BUILD.gn:34 When set (the default) enables C++ iterator debugging in debug builds. Iterator debugging is always off in release builds (technically, this flag affects the "debug" config, which is always available but applied by default only in debug builds). Iterator debugging is generally useful for catching bugs. But it can introduce extra locking to check the state of an iterator against the state of the current object. For iterator- and thread-heavy code, this can significantly slow execution. enable_nacl Current value (from the default) = true From //build/config/features.gni:27 Enables Native Client support. Temporarily disable nacl on arm64 linux to get rid of compilation errors. TODO(mcgrathr): When mipsel-nacl-clang is available, drop the exclusion. enable_nacl_nonsfi Current value (from the default) = true From //build/config/features.gni:32 Non-SFI is not yet supported on mipsel enable_precompiled_headers Current value (from the default) = true From //build/config/pch.gni:11 Precompiled header file support is by default available, but for distributed build system uses (like goma) or when doing official builds. enable_profiling Current value (from the default) = false From //build/config/compiler/compiler.gni:28 Compile in such a way as to enable profiling of the generated code. For example, don't omit the frame pointer and leave in symbols. enable_resource_whitelist_generation Current value (from the default) = false From //build/config/android/config.gni:369 Enables used resource whitelist generation. Set for official builds only as a large amount of build output is generated. enable_stripping Current value (from the default) = false From //build/config/mac/symbols.gni:24 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. exclude_unwind_tables Current value (from the default) = false From //build/config/compiler/BUILD.gn:74 Omit unwind support in official builds to save space. We can use breakpad for these builds. fatal_linker_warnings Current value (from the default) = true From //build/config/compiler/BUILD.gn:86 Enable fatal linker warnings. Building Chromium with certain versions of binutils can cause linker warning. See: https://bugs.chromium.org/p/chromium/issues/detail?id=457359 fieldtrial_testing_like_official_build Current value (from the default) = false From //build/config/features.gni:56 Set to true make a build that disables activation of field trial tests specified in testing/variations/fieldtrial_testing_config_*.json. Note: this setting is ignored if is_chrome_branded. full_wpo_on_official Current value (from the default) = false From //build/config/compiler/compiler.gni:119 gcc_target_rpath Current value (from the default) = "" From //build/config/gcc/BUILD.gn:18 When non empty, overrides the target rpath value. This allows a user to make a Chromium build where binaries and shared libraries are meant to be installed into separate directories, like /usr/bin/chromium and /usr/lib/chromium for instance. It is useful when a build system that generates a whole target root filesystem (like Yocto) is used on top of gn, especially when cross-compiling. Note: this gn arg is similar to gyp target_rpath generator flag. generate_linker_map Current value (from the default) = false From //build/toolchain/toolchain.gni:44 Used for binary size analysis. Currently disabled on LLD because of a bug (fixed upstream). See https://crbug.com/716209. gold_path Current value (from the default) = false From //build/config/compiler/BUILD.gn:63 When we are going to use gold we need to find it. This is initialized below, after use_gold might have been overridden. goma_dir Current value (from the default) = "/Users/ilong/goma" From //build/toolchain/goma.gni:17 Absolute directory containing the gomacc binary. host_cpu Current value (from the default) = "x64" (Internally set; try `gn help host_cpu`.) host_os Current value (from the default) = "mac" (Internally set; try `gn help host_os`.) host_pkg_config Current value (from the default) = "" From //build/config/linux/pkg_config.gni:36 A optional pkg-config wrapper to use for tools built on the host. host_toolchain Current value (from the default) = "" From //build/config/BUILDCONFIG.gn:151 This should not normally be set as a build argument. It's here so that every toolchain can pass through the "global" value via toolchain_args(). ios_app_bundle_id_prefix Current value (from the default) = "org.chromium" From //build/config/ios/ios_sdk.gni:33 Prefix for CFBundleIdentifier property of iOS bundles (correspond to the "Organization Identifier" in Xcode). Code signing will fail if no mobile provisioning for the selected code signing identify support that prefix. ios_automatically_manage_certs Current value (from the default) = true From //build/config/ios/ios_sdk.gni:39 If true, then allow using Xcode to automatically manage certificates. This requires loading a separate Xcode project and enable automatically managed certificates. When true, all test application will use the same bundle id to avoid running out of certificates if using a free account. ios_code_signing_identity Current value (from the default) = "" From //build/config/ios/ios_sdk.gni:27 ios_code_signing_identity_description Current value (from the default) = "iPhone Developer" From //build/config/ios/ios_sdk.gni:28 ios_deployment_target Current value (from the default) = "9.0" From //build/config/ios/ios_sdk.gni:21 Version of iOS that we're targeting. ios_enable_code_signing Current value (from the default) = true From //build/config/ios/ios_sdk.gni:26 The iOS Code signing identity to use TODO(GYP), TODO(sdfresne): Consider having a separate ios_enable_code_signing_flag=<bool> flag to make the invocation clearer. ios_enable_coverage Current value (from the default) = false From //build/config/ios/ios_sdk.gni:43 Enabling this option makes clang compile for profiling to gather code coverage metrics. ios_sdk_name Current value (from the default) = "" From //build/config/ios/ios_sdk.gni:11 ios_sdk_path Current value (from the default) = "" From //build/config/ios/ios_sdk.gni:10 SDK path to use. When empty this will use the default SDK based on the value of use_ios_simulator. ios_sdk_platform Current value (from the default) = "" From //build/config/ios/ios_sdk.gni:13 ios_sdk_platform_path Current value (from the default) = "" From //build/config/ios/ios_sdk.gni:14 ios_sdk_version Current value (from the default) = "" From //build/config/ios/ios_sdk.gni:12 is_asan Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:11 Compile for Address Sanitizer to find memory bugs. is_cast_audio_only Current value (from the default) = false From //build/config/chromecast_build.gni:14 Set this true for an audio-only Chromecast build. is_cast_desktop_build Current value (from the default) = false From //build/config/chromecast_build.gni:26 True if Chromecast build is targeted for linux desktop. This type of build is useful for testing and development, but currently supports only a subset of Cast functionality. Though this defaults to true for x86 Linux devices, this should be overriden manually for an embedded x86 build. TODO(slan): Remove instances of this when x86 is a fully supported platform. is_cfi Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:58 Compile with Control Flow Integrity to protect virtual calls and casts. See http://clang.llvm.org/docs/ControlFlowIntegrity.html TODO(pcc): Remove this flag if/when CFI is enabled in all official builds. is_chrome_branded Current value (from the default) = false From //build/config/chrome_build.gni:9 Select the desired branding flavor. False means normal Chromium branding, true means official Google Chrome branding (requires extra Google-internal resources). is_chromecast Current value (from the default) = false From //build/config/chromecast_build.gni:11 Set this true for a Chromecast build. Chromecast builds are supported on Linux and Android. is_clang Current value (from the default) = true From //build/config/BUILDCONFIG.gn:139 is_component_build Current value = false From //.gn:38 Overridden from the default = false From //build/config/BUILDCONFIG.gn:169 is_debug Current value (from the default) = true From //build/config/BUILDCONFIG.gn:158 Debug build. Enabling official builds automatically sets is_debug to false. is_desktop_linux Current value (from the default) = false From //build/config/BUILDCONFIG.gn:134 Whether we're a traditional desktop unix. is_lsan Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:14 Compile for Leak Sanitizer to find leaks. is_msan Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:17 Compile for Memory Sanitizer to find uninitialized reads. is_multi_dll_chrome Current value (from the default) = false From //build/config/chrome_build.gni:13 Break chrome.dll into multple pieces based on process type. Only available on Windows. is_official_build Current value (from the default) = false From //build/config/BUILDCONFIG.gn:131 Set to enable the official build level of optimization. This has nothing to do with branding, but enables an additional level of optimization above release (!is_debug). This might be better expressed as a tri-state (debug, release, official) but for historical reasons there are two separate flags. is_syzyasan Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:52 Enable building with SyzyAsan which can find certain types of memory errors. Only works on Windows. See https://github.com/google/syzygy/wiki/SyzyASanHowTo is_tsan Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:20 Compile for Thread Sanitizer to find threading bugs. is_ubsan Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:24 Compile for Undefined Behaviour Sanitizer to find various types of undefined behaviour (excludes vptr checks). is_ubsan_no_recover Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:27 Halt the program if a problem is detected. is_ubsan_null Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:30 Compile for Undefined Behaviour Sanitizer's null pointer checks. is_ubsan_security Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:87 Enables core ubsan security features. Will later be removed once it matches is_ubsan. is_ubsan_vptr Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:33 Compile for Undefined Behaviour Sanitizer's vptr checks. is_win_fastlink Current value (from the default) = false From //build/config/compiler/compiler.gni:45 Tell VS to create a PDB that references information in .obj files rather than copying it all. This should improve linker performance. mspdbcmf.exe can be used to convert a fastlink pdb to a normal one. libcpp_is_static Current value (from the default) = true From //build/config/c++/c++.gni:33 ASan, MSan and TSan builds need to override operator new, operator delete, and some exception handling symbols, so libc++ must be a shared library to prevent duplicate symbol errors when linking. Additionally, -fsanitize=vptr requires libc++ to be a shared library because the ubsan runtime library that implements -fsanitize=vptr calls dynamic_cast with the ABI type info classes, which won't return the right answer if each DSO has its own copy of the ABI classes. libyuv_disable_jpeg Current value (from the default) = false From //third_party/libyuv/libyuv.gni:15 libyuv_include_tests Current value (from the default) = true From //third_party/libyuv/libyuv.gni:14 libyuv_use_gflags Current value (from the default) = true From //third_party/libyuv/BUILD.gn:14 Set to false to disable building with gflags. libyuv_use_msa Current value (from the default) = false From //third_party/libyuv/libyuv.gni:18 libyuv_use_neon Current value (from the default) = true From //third_party/libyuv/libyuv.gni:16 linkrepro_root_dir Current value (from the default) = "" From //build/config/compiler/compiler.gni:63 Root directory that will store the MSVC link repro. This should only be used for debugging purposes on the builders where a MSVC linker flakyness has been observed. The targets for which a link repro should be generated should add somethink like this to their configuration: if (linkrepro_root_dir != "") { ldflags = ["/LINKREPRO:" + linkrepro_root_dir + "/" + target_name] } Note that doing a link repro uses a lot of disk space and slows down the build, so this shouldn't be enabled on too many targets. See crbug.com/669854. linux_use_bundled_binutils Current value (from the default) = false From //build/config/compiler/BUILD.gn:49 llvm_force_head_revision Current value (from the default) = false From //build/toolchain/toolchain.gni:34 If this is set to true, or if LLVM_FORCE_HEAD_REVISION is set to 1 in the environment, we use the revision in the llvm repo to determine the CLANG_REVISION to use, instead of the version hard-coded into //tools/clang/scripts/update.py. This should only be used in conjunction with setting LLVM_FORCE_HEAD_REVISION in the environment when `gclient runhooks` is run as well. mac_deployment_target Current value (from the default) = "10.9.0" From //build/config/mac/mac_sdk.gni:12 Minimum supported version of macOS. Must be of the form x.x.x for Info.plist files. mac_sdk_min Current value = "10.11" From //.gn:40 Overridden from the default = "10.12" From //build/config/mac/mac_sdk_overrides.gni:12 mac_sdk_name Current value (from the default) = "macosx" From //build/config/mac/mac_sdk.gni:20 The SDK name as accepted by xcodebuild. mac_sdk_path Current value (from the default) = "" From //build/config/mac/mac_sdk.gni:17 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 to mac_sdk_min is used. machine_os_build Current value (from the default) = "" From //build/config/ios/ios_sdk.gni:18 msan_track_origins Current value (from the default) = 2 From //build/config/sanitizers/sanitizers.gni:38 Track where uninitialized memory originates from. From fastest to slowest: 0 - no tracking, 1 - track only the initial allocation site, 2 - track the chain of stores leading from allocation site to use site. msvc_use_absolute_paths Current value (from the default) = false From //build/toolchain/toolchain.gni:48 Use absolute file paths in the compiler diagnostics and __FILE__ macro if needed. optimize_for_fuzzing Current value (from the default) = false From //build/config/compiler/BUILD.gn:101 Optimize for coverage guided fuzzing (balance between speed and number of branches) optimize_for_size Current value (from the default) = false From //build/config/compiler/BUILD.gn:81 If true, optimize for size. Does not affect windows builds. Linux & Mac favor speed over size. TODO(brettw) it's weird that Mac and desktop Linux are different. We should explore favoring size over speed in this case as well. pgo_data_path Current value (from the default) = "" From //build/config/compiler/pgo/pgo.gni:16 When using chrome_pgo_phase = 2, read profile data from this path. pkg_config Current value (from the default) = "" From //build/config/linux/pkg_config.gni:33 A pkg-config wrapper to call instead of trying to find and call the right pkg-config directly. Wrappers like this are common in cross-compilation environments. Leaving it blank defaults to searching PATH for 'pkg-config' and relying on the sysroot mechanism to find the right .pc files. proprietary_codecs Current value (from the default) = false From //build/config/features.gni:39 Enables proprietary codecs and demuxers; e.g. H264, AAC, MP3, and MP4. We always build Google Chrome and Chromecast with proprietary codecs. Note: this flag is used by WebRTC which is DEPSed into Chrome. Moving it out of //build will require using the build_overrides directory. rtc_audio_device_plays_sinus_tone Current value (from the default) = false From //webrtc/webrtc.gni:157 When set to true, replace the audio output with a sinus tone at 440Hz. The ADM will ask for audio data from WebRTC but instead of reading real audio samples from NetEQ, a sinus tone will be generated and replace the real audio samples. rtc_build_json Current value (from the default) = true From //webrtc/webrtc.gni:78 Disable these to not build components which can be externally provided. rtc_build_libevent Current value (from the default) = false From //webrtc/webrtc.gni:115 rtc_build_libsrtp Current value (from the default) = true From //webrtc/webrtc.gni:79 rtc_build_libvpx Current value (from the default) = true From //webrtc/webrtc.gni:80 rtc_build_libyuv Current value (from the default) = true From //webrtc/webrtc.gni:82 rtc_build_openmax_dl Current value (from the default) = true From //webrtc/webrtc.gni:83 rtc_build_opus Current value (from the default) = true From //webrtc/webrtc.gni:84 rtc_build_ssl Current value (from the default) = true From //webrtc/webrtc.gni:85 rtc_build_usrsctp Current value (from the default) = true From //webrtc/webrtc.gni:86 rtc_build_with_neon Current value (from the default) = true From //webrtc/webrtc.gni:134 rtc_enable_android_opensl Current value (from the default) = false From //webrtc/webrtc.gni:91 rtc_enable_bwe_test_logging Current value (from the default) = false From //webrtc/webrtc.gni:72 Set this to true to enable BWE test logging. rtc_enable_external_auth Current value (from the default) = false From //webrtc/webrtc.gni:65 Enable when an external authentication mechanism is used for performing packet authentication for RTP packets instead of libsrtp. rtc_enable_intelligibility_enhancer Current value (from the default) = false From //webrtc/webrtc.gni:61 Disable the code for the intelligibility enhancer by default. rtc_enable_libevent Current value (from the default) = false From //webrtc/webrtc.gni:114 rtc_enable_protobuf Current value (from the default) = true From //webrtc/webrtc.gni:58 Enables the use of protocol buffers for debug recordings. rtc_enable_sctp Current value (from the default) = true From //webrtc/webrtc.gni:75 Set this to disable building with support for SCTP data channels. rtc_include_ilbc Current value (from the default) = true From //webrtc/webrtc.gni:180 Include the iLBC audio codec? rtc_include_internal_audio_device Current value (from the default) = true From //webrtc/webrtc.gni:189 Chromium uses its own IO handling, so the internal ADM is only built for standalone WebRTC. rtc_include_opus Current value (from the default) = true From //webrtc/webrtc.gni:37 Disable this to avoid building the Opus audio codec. rtc_include_pulse_audio Current value (from the default) = true From //webrtc/webrtc.gni:185 Excluded in Chromium since its prerequisites don't require Pulse Audio. rtc_include_tests Current value (from the default) = true From //webrtc/webrtc.gni:192 Include tests in standalone checkout. rtc_initialize_ffmpeg Current value (from the default) = true From //webrtc/webrtc.gni:168 FFmpeg must be initialized for |H264DecoderImpl| to work. This can be done by WebRTC during |H264DecoderImpl::InitDecode| or externally. FFmpeg must only be initialized once. Projects that initialize FFmpeg externally, such as Chromium, must turn this flag off so that WebRTC does not also initialize. rtc_jsoncpp_root Current value (from the default) = "//third_party/jsoncpp/source/include" From //webrtc/webrtc.gni:48 Used to specify an external Jsoncpp include path when not compiling the library that comes with WebRTC (i.e. rtc_build_json == 0). rtc_libvpx_build_vp9 Current value (from the default) = true From //webrtc/webrtc.gni:81 rtc_link_task_queue_impl Current value (from the default) = true From //webrtc/webrtc.gni:108 Links a default implementation of task queues to targets that depend on the target rtc_task_queue. Set to false to use an external implementation. rtc_opus_support_120ms_ptime Current value (from the default) = true From //webrtc/webrtc.gni:41 Enable this if the Opus version upon which WebRTC is built supports direct encoding of 120 ms packets. rtc_opus_variable_complexity Current value (from the default) = false From //webrtc/webrtc.gni:44 Enable this to let the Opus audio codec change complexity on the fly. rtc_prefer_fixed_point Current value (from the default) = true From //webrtc/webrtc.gni:122 rtc_restrict_logging Current value (from the default) = false From //webrtc/webrtc.gni:182 rtc_sanitize_coverage Current value (from the default) = "" From //webrtc/webrtc.gni:103 Set to "func", "block", "edge" for coverage generation. At unit test runtime set UBSAN_OPTIONS="coverage=1". It is recommend to set include_examples=0. Use llvm's sancov -html-report for human readable reports. See http://clang.llvm.org/docs/SanitizerCoverage.html . rtc_ssl_root Current value (from the default) = "" From //webrtc/webrtc.gni:52 Used to specify an external OpenSSL include path when not compiling the library that comes with WebRTC (i.e. rtc_build_ssl == 0). rtc_use_dummy_audio_file_devices Current value (from the default) = false From //webrtc/webrtc.gni:151 By default, use normal platform audio support or dummy audio, but don't use file-based audio playout and record. rtc_use_gtk Current value (from the default) = true From //webrtc/webrtc.gni:172 Build sources requiring GTK. NOTICE: This is not present in Chrome OS build environments, even if available for Chromium builds. rtc_use_h264 Current value (from the default) = false From //webrtc/webrtc.gni:144 Enable this to build OpenH264 encoder/FFmpeg decoder. This is supported on all platforms except Android and iOS. Because FFmpeg can be built with/without H.264 support, |ffmpeg_branding| has to separately be set to a value that includes H.264, for example "Chrome". If FFmpeg is built without H.264, compilation succeeds but |H264DecoderImpl| fails to initialize. See also: |rtc_initialize_ffmpeg|. CHECK THE OPENH264, FFMPEG AND H.264 LICENSES/PATENTS BEFORE BUILDING. http://www.openh264.org, https://www.ffmpeg.org/ rtc_use_lto Current value (from the default) = false From //webrtc/webrtc.gni:96 Link-Time Optimizations. Executes code generation at link-time instead of compile-time. https://gcc.gnu.org/wiki/LinkTimeOptimization rtc_use_memcheck Current value (from the default) = false From //webrtc/webrtc.gni:161 When set to true, test targets will declare the files needed to run memcheck as data dependencies. This is to enable memcheck execution on swarming bots. rtc_use_metal_rendering Current value (from the default) = true From //webrtc/sdk/BUILD.gn:17 Determine whether or not to include metal rendering rtc_use_openmax_dl Current value (from the default) = false From //webrtc/webrtc.gni:129 rtc_use_quic Current value (from the default) = false From //webrtc/webrtc.gni:147 Determines whether QUIC code will be built. safe_browsing_mode Current value (from the default) = 1 From //build/config/features.gni:50 sanitizer_coverage_flags Current value (from the default) = "" From //build/config/sanitizers/sanitizers.gni:103 Value for -fsanitize-coverage flag. Setting this causes use_sanitizer_coverage to be enabled. Default value when unset and use_afl=true or use_libfuzzer=true: trace-pc-guard Default value when unset and use_sanitizer_coverage=true: trace-pc-guard,indirect-calls sanitizer_keep_symbols Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:109 Keep symbol level when building with sanitizers. When sanitizers are enabled, the default is to compile with the minimum debug info level necessary, overriding any other symbol level arguments that may be set. Setting this to true prevents this. strip_absolute_paths_from_debug_symbols Current value (from the default) = false From //build/config/compiler/BUILD.gn:106 Optimize symbol files for maximizing goma cache hit rate. This isn't on by default when goma is enabled because setting this to true may make it harder to debug binaries. symbol_level Current value (from the default) = -1 From //build/config/compiler/compiler.gni:24 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. -1 means auto-set according to debug/release and platform. system_libdir Current value (from the default) = "lib" From //build/config/linux/pkg_config.gni:47 CrOS systemroots place pkgconfig files at <systemroot>/usr/share/pkgconfig and one of <systemroot>/usr/lib/pkgconfig or <systemroot>/usr/lib64/pkgconfig depending on whether the systemroot is for a 32 or 64 bit architecture. When build under GYP, CrOS board builds specify the 'system_libdir' variable as part of the GYP_DEFINES provided by the CrOS emerge build or simple chrome build scheme. This variable permits controlling this for GN builds in similar fashion by setting the `system_libdir` variable in the build's args.gn file to 'lib' or 'lib64' as appropriate for the target architecture. target_cpu Current value = "arm64" From //out/ios/args.gn:2 Overridden from the default = "" (Internally set; try `gn help target_cpu`.) target_os Current value = "ios" From //out/ios/args.gn:1 Overridden from the default = "" (Internally set; try `gn help target_os`.) target_sysroot Current value (from the default) = "" From //build/config/sysroot.gni:13 The absolute path of the sysroot that is applied when compiling using the target toolchain. target_sysroot_dir Current value (from the default) = "//build/linux" From //build/config/sysroot.gni:16 The absolute path to directory containing linux sysroot images toolkit_views Current value (from the default) = true From //build/config/ui.gni:42 True means the UI is built using the "views" framework. treat_warnings_as_errors Current value (from the default) = true From //build/config/compiler/BUILD.gn:38 Default to warnings as errors for default workflow, where we catch warnings with known toolchains. Allow overriding this e.g. for Chromium builds on Linux that could use a different version of the compiler. With GCC, warnings in no-Chromium code are always not treated as errors. use_afl Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:83 Compile for fuzzing with AFL. use_allocator Current value (from the default) = "none" From //build/config/allocator.gni:29 Memory allocator to use. Set to "none" to use default allocator. use_allocator_shim Current value (from the default) = true From //build/config/allocator.gni:32 Causes all the allocations to be routed via allocator_shim.cc. use_ash Current value (from the default) = false From //build/config/ui.gni:25 Indicates if Ash is enabled. Ash is the Aura Shell which provides a desktop-like environment for Aura. Requires use_aura = true use_aura Current value (from the default) = false From //build/config/ui.gni:34 Indicates if Aura is enabled. Aura is a low-level windowing library, sort of a replacement for GDI or GTK. use_cfi_cast Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:64 Enable checks for bad casts: derived cast and unrelated cast. TODO(krasin): remove this, when we're ready to add these checks by default. https://crbug.com/626794 use_cfi_diag Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:72 Print detailed diagnostics when Control Flow Integrity detects a violation. use_cfi_icall Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:69 Enable checks for indirect function calls via a function pointer. TODO(pcc): remove this when we're ready to add these checks by default. https://crbug.com/701919 use_cfi_recover Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:76 Let Control Flow Integrity continue execution instead of crashing when printing diagnostics (use_cfi_diag = true). use_clang_static_analyzer Current value (from the default) = false From //build/toolchain/clang_static_analyzer.gni:10 Uses the Clang static analysis tools during compilation. use_custom_libcxx Current value (from the default) = false From //build/config/c++/c++.gni:14 use_custom_libcxx_for_host Current value (from the default) = false From //build/config/c++/c++.gni:24 Use libc++ instead of stdlibc++ when using the host_cpu toolchain, even if use_custom_libcxx is false. This is useful for cross-compiles where a custom toolchain for the target_cpu has been set as the default toolchain, but use_custom_libcxx should still be true when building for the host. The expected usage is to set use_custom_libcxx=false and use_custom_libcxx_for_host=true in the passed in buildargs. use_cxx11 Current value = true From //.gn:43 Overridden from the default = false From //build/config/compiler/BUILD.gn:109 Allow projects that wish to stay on C++11 to override Chromium's default. use_cxx11_on_android Current value = false From //.gn:46 Overridden from the default = true From //build/config/compiler/BUILD.gn:114 C++11 may not be an option if Android test infrastructure is used. use_dbus Current value (from the default) = false From //build/config/features.gni:61 use_debug_fission Current value (from the default) = "default" From //build/config/compiler/compiler.gni:40 use_debug_fission: whether to use split DWARF debug info files. This can reduce link time significantly, but is incompatible with some utilities such as icecc and ccache. Requires gold and gcc >= 4.8 or clang. http://gcc.gnu.org/wiki/DebugFission This is a placeholder value indicating that the code below should set the default. This is necessary to delay the evaluation of the default value expression until after its input values such as use_gold have been set, e.g. by a toolchain_args() block. use_drfuzz Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:91 Compile for fuzzing with Dr. Fuzz See http://www.chromium.org/developers/testing/dr-fuzz use_gconf Current value (from the default) = false From //build/config/features.gni:65 Option controlling the use of GConf (the classic GNOME configuration system). use_gio Current value (from the default) = false From //build/config/features.gni:68 use_glib Current value (from the default) = false From //build/config/ui.gni:37 Whether we should use glib, a low level C utility library. use_gold Current value (from the default) = false From //build/config/compiler/compiler.gni:134 use_goma Current value (from the default) = false From //build/toolchain/goma.gni:9 Set to true to enable distributed compilation using Goma. use_incremental_wpo Current value (from the default) = false From //build/config/compiler/compiler.gni:49 Whether or not we should turn on incremental WPO. Only affects the VS Windows build. use_libfuzzer Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:80 Compile for fuzzing with LLVM LibFuzzer. See http://www.chromium.org/developers/testing/libfuzzer use_lld Current value (from the default) = false From //build/config/compiler/compiler.gni:126 Set to true to use lld, the LLVM linker. This flag may be used on Windows, Linux or Fuchsia. use_locally_built_instrumented_libraries Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:47 Use dynamic libraries instrumented by one of the sanitizers instead of the standard system libraries. Set this flag to build the libraries from source. use_ozone Current value (from the default) = false From //build/config/ui.gni:30 Indicates if Ozone is enabled. Ozone is a low-level library layer for Linux that does not require X11. Enabling this feature disables use of glib, x11, Pango, and Cairo. use_pic Current value (from the default) = true From //build/config/compiler/compiler.gni:66 Whether or not we should use position independent code. use_prebuilt_instrumented_libraries Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:43 Use dynamic libraries instrumented by one of the sanitizers instead of the standard system libraries. Set this flag to download prebuilt binaries from GCS. use_rtti Current value (from the default) = false From //build/config/compiler/BUILD.gn:91 Build with C++ RTTI enabled. Chromium builds without RTTI by default, but some sanitizers are known to require it, like CFI diagnostics and UBsan variants. use_sanitizer_coverage Current value (from the default) = false From //build/config/sanitizers/sanitizers.gni:143 use_sysroot Current value (from the default) = true From //build/config/sysroot.gni:19 use_thin_lto Current value (from the default) = false From //build/toolchain/toolchain.gni:25 If used with allow_posix_link_time_opt, it enables support for ThinLTO, which links 3x-10x faster than full LTO. See also http://blog.llvm.org/2016/06/thinlto-scalable-and-incremental-lto.html use_udev Current value (from the default) = false From //build/config/features.gni:59 libudev usage. This currently only affects the content layer. use_xcode_clang Current value (from the default) = false From //build/toolchain/toolchain.gni:39 Compile with Xcode version of clang instead of hermetic version shipped with the build. Used on iOS to ship official builds (as they are built with the version of clang shipped with Xcode). v8_current_cpu Current value (from the default) = "arm64" From //build/config/v8_target_cpu.gni:60 This argument is declared here so that it can be overridden in toolchains. It should never be explicitly set by the user. v8_target_cpu Current value (from the default) = "" From //build/config/v8_target_cpu.gni:33 This arg is used when we want to tell the JIT-generating v8 code that we want to have it generate for an architecture that is different than the architecture that v8 will actually run on; we then run the code under an emulator. For example, we might run v8 on x86, but generate arm code and run that under emulation. This arg is defined here rather than in the v8 project because we want some of the common architecture-specific args (like arm_float_abi or mips_arch_variant) to be set to their defaults either if the current_cpu applies *or* if the v8_current_cpu applies. As described below, you can also specify the v8_target_cpu to use indirectly by specifying a `custom_toolchain` that contains v8_$cpu in the name after the normal toolchain. For example, `gn gen --args="custom_toolchain=...:clang_x64_v8_arm64"` is equivalent to setting --args=`v8_target_cpu="arm64"`. Setting `custom_toolchain` is more verbose but makes the toolchain that is (effectively) being used explicit. v8_target_cpu can only be used to target one architecture in a build, so if you wish to build multiple copies of v8 that are targeting different architectures, you will need to do something more complicated involving multiple toolchains along the lines of custom_toolchain, above. xcode_build Current value (from the default) = "" From //build/config/ios/ios_sdk.gni:17 xcode_version Current value (from the default) = "" From //build/config/ios/ios_sdk.gni:15 xcode_version_int Current value (from the default) = 0 From //build/config/ios/ios_sdk.gni:16