[NaCl SDK] Make ARM cross compiler optional until trybots get updated.

native_client_sdk/src/build_tools/build_sdk.py

 #!/usr/bin/env python
 # Copyright (c) 2012 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.
 
 """Entry point for both build and try bots.
 
 This script is invoked from XXX, usually without arguments
 to package an SDK. It automatically determines whether
 this SDK is for mac, win, linux.
@@ skipping 519 matching lines @@
                   out_dir, force_arm_gcc=True):
   gyp_env = dict(os.environ)
   gyp_env['GYP_GENERATORS'] = 'ninja'
   gyp_defines = []
   if options.mac_sdk:
     gyp_defines.append('mac_sdk=%s' % options.mac_sdk)
   if arch:
     gyp_defines.append('target_arch=%s' % arch)
     if arch == 'arm':
       if getos.GetPlatform() == 'linux':
-        gyp_env['CC'] = 'arm-linux-gnueabihf-gcc'
-        gyp_env['CXX'] = 'arm-linux-gnueabihf-g++'
-        gyp_env['AR'] = 'arm-linux-gnueabihf-ar'
-        gyp_env['AS'] = 'arm-linux-gnueabihf-as'
-        gyp_env['CC_host'] = 'cc'
-        gyp_env['CXX_host'] = 'c++'
+        if os.path.exists("/usr/bin/arm-linux-gnueabihf-gcc"):

[binji, 2014/01/22 22:33:47]

shouldn't this just skip the arm build entirely instead if the compiler doesn't
exist?

[Sam Clegg, 2014/01/22 22:36:04]

The current nacl gyp files require the arm cross compiler when you in order to
build the nacl_core_sdk gyp target.

There is a NaCl side revert that removes this requirement but I'd
like to put that back once the bots have the compiler installed.

+          # TODO(sbc): make this conditional once all our linux
+          # have the ARM cross compiler installed.
+          gyp_env['CC'] = 'arm-linux-gnueabihf-gcc'
+          gyp_env['CXX'] = 'arm-linux-gnueabihf-g++'
+          gyp_env['AR'] = 'arm-linux-gnueabihf-ar'
+          gyp_env['AS'] = 'arm-linux-gnueabihf-as'
+          gyp_env['CC_host'] = 'cc'
+          gyp_env['CXX_host'] = 'c++'
       gyp_defines += ['armv7=1', 'arm_thumb=0', 'arm_neon=1',
           'arm_float_abi=hard']
       if force_arm_gcc:
         gyp_defines.append('nacl_enable_arm_gcc=1')
   if getos.GetPlatform() == 'mac':
     gyp_defines.append('clang=1')
 
   gyp_env['GYP_DEFINES'] = ' '.join(gyp_defines)
   for key in ['GYP_GENERATORS', 'GYP_DEFINES', 'CC']:
     value = gyp_env.get(key)
@@ skipping 436 matching lines @@
     BuildStepArchiveSDKTools()
 
   return 0
 
 
 if __name__ == '__main__':
   try:
     sys.exit(main(sys.argv))
   except KeyboardInterrupt:
     buildbot_common.ErrorExit('build_sdk: interrupted')