Download sysroot from "commondatastorage.googleapis.com"

build/linux/sysroot_scripts/install-sysroot.py

 #!/usr/bin/env python
 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Install Debian Wheezy sysroots for building chromium.
 """
 
 # The sysroot is needed to ensure that binaries will run on Debian Wheezy,
 # the oldest supported linux distribution.  This script can be run manually but
@@ skipping 73 matching lines @@
     return 'mips'
 
   raise Error('Unrecognized host arch: %s' % detected_host_arch)
 
 
 def DetectTargetArch():
   """Attempt for determine target architecture.
 
   This works by looking for target_arch in GYP_DEFINES.
   """
-  # TODO(agrieve): Make this script not depend on GYP_DEFINES so that it works
-  #     with GN as well.
-  gyp_environment.SetEnvironment()
-  supplemental_includes = gyp_chromium.GetSupplementalFiles()
-  gyp_defines = gyp_chromium.GetGypVars(supplemental_includes)
   target_arch = gyp_defines.get('target_arch')
   if target_arch == 'x64':
     return 'amd64'
   elif target_arch == 'ia32':
     return 'i386'
   elif target_arch == 'arm':
     return 'arm'
   elif target_arch == 'arm64':
     return 'arm64'
   elif target_arch == 'mipsel':
@@ skipping 23 matching lines @@
   # architecture.
   target_arch = DetectTargetArch()
   if target_arch and target_arch not in (host_arch, 'i386', 'arm64'):
     InstallSysroot(target_arch)
 
 
 def main():
   if options.running_as_hook and not sys.platform.startswith('linux'):
     return 0
 
+  if gyp_defines.has_key('use_sysroot') \
+      and int(gyp_defines['use_sysroot']) == 0:

[Sam Clegg, 2015/12/17 22:17:06]

What about just `gyp_defines.get('use_sysroot') == '0':`

+    return 0
+
   if options.running_as_hook:
     InstallDefaultSysroots()
   else:
     if not options.arch:
       print 'You much specify either --arch or --running-as-hook'
       return 1
     InstallSysroot(options.arch)
 
   return 0
 
@@ skipping 57 matching lines @@
 
 
 if __name__ == '__main__':
   parser = optparse.OptionParser('usage: %prog [OPTIONS]', description=__doc__)
   parser.add_option('--running-as-hook', action='store_true',
                     default=False, help='Used when running from gclient hooks.'
                                         ' Installs default sysroot images.')
   parser.add_option('--arch', type='choice', choices=valid_archs,
                     help='Sysroot architecture: %s' % ', '.join(valid_archs))
   options, _ = parser.parse_args()
+
+  # TODO(agrieve): Make this script not depend on GYP_DEFINES so that it works
+  #     with GN as well.
+  gyp_environment.SetEnvironment()
+  supplemental_includes = gyp_chromium.GetSupplementalFiles()
+  gyp_defines = gyp_chromium.GetGypVars(supplemental_includes)

[Sam Clegg, 2015/12/17 22:15:45]

Can you do this in main and pass gyp_defines to DetectTargetArch().

+
   sys.exit(main())