tools/gn.py -v '--mode=release' --goma '--target-sysroot=simarm64=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk,x64=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk' '--arch=x64' --platform-sdk
in dir /b/s/w/ir/k/dart/sdk:
 allow_subannotations: False
 base_name: 'gn host (x64)'
 cmd: ['tools/gn.py',
 '-v',
 '--mode=release',
 '--goma',
 '--target-sysroot=simarm64=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk,x64=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk',
 '--arch=x64',
 '--platform-sdk']
 cwd: '/b/s/w/ir/k/dart/sdk'
 env: {}
 env_prefixes: {}
 env_suffixes: {}
 infra_step: False
 name: 'gn host (x64)'
 nest_level: 0
 ok_ret: frozenset([0])
 trigger_specs: ()
full environment:
 BOTO_CONFIG: /b/s/w/ir/tmp/gsutil_task/.boto
 BUILDBUCKET_EXPERIMENTAL: FALSE
 CIPD_CACHE_DIR: /b/s/cipd_cache/cache
 CIPD_PROTOCOL: v2
 DEVSHELL_CLIENT_PORT: 51346
 DOCKER_CONFIG: /b/s/w/ir/tmp/docker_cfg_task
 DOCKER_TMPDIR: /b/s/w/ir/tmp/docker_tmp_task
 GIT_CONFIG_NOSYSTEM: 1
 GIT_TERMINAL_PROMPT: 0
 HOME: /Users/swarming
 INFRA_GIT_WRAPPER_HOME: /b/s/w/ir/tmp/git_home_task
 LOGDOG_COORDINATOR_HOST: logs.chromium.org
 LOGDOG_STREAM_PREFIX: buildbucket/cr-buildbucket.appspot.com/8918442817039475872
 LOGDOG_STREAM_PROJECT: fuchsia
 LOGDOG_STREAM_SERVER_PATH: unix:/b/s/w/ir/tmp/ld.sock
 LOGNAME: swarming
 LUCI_CONTEXT: /b/s/w/it3DjVpR/luci_context.748975968
 MAC_CHROMIUM_TMPDIR: /b/s/w/ir/tmp/t
 NO_GCE_CHECK: False
 PATH: /b/s/w/ir/cipd_bin_packages:/b/s/w/ir/cipd_bin_packages/bin:/b/s/cipd_cache/bin:/usr/local/bin:/usr/bin:/bin:/usr/local/sbin:/usr/sbin:/sbin
 PWD: /b/s/w/ir/k
 PYTHONIOENCODING: UTF-8
 PYTHONUNBUFFERED: 1
 SHELL: /bin/bash
 SHLVL: 1
 SWARMING_BOT_ID: fuchsia-ci-mac-lab01-1003
 SWARMING_EXTERNAL_BOT_SETUP: 1
 SWARMING_HEADLESS: 1
 SWARMING_SERVER: https://chromium-swarm.appspot.com
 SWARMING_TASK_ID: 43b5382925fddd11
 TEMP: /b/s/w/ir/tmp/t
 TEMPDIR: /b/s/w/ir/tmp/t
 TMP: /b/s/w/ir/tmp/t
 TMPDIR: /b/s/w/ir/tmp/t
 USER: swarming
 VERSIONER_PYTHON_PREFER_32_BIT: no
 VERSIONER_PYTHON_VERSION: 2.7
 VPYTHON_VIRTUALENV_ROOT: /b/s/w/ir/cache/vpython
 XPC_FLAGS: 0x0
 XPC_SERVICE_NAME: 0
 _: /b/s/w/ir/cipd_bin_packages/vpython
 __CF_USER_TEXT_ENCODING: 0x1F6:0:0

gn gen --check in xcodebuild/ReleaseX64
GN Time: 1.074 seconds