Adding support for building V8 for ARM with snapshot using the crosstool comp...

SConstruct

 # Copyright 2008 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 285 matching lines @@
     'values': ['freebsd', 'linux', 'macos', 'win32'],
     'default': OS_GUESS,
     'help': 'the os to build for'
   },
   'arch': {
     'values':['arm', 'ia32'],
     'default': ARCH_GUESS,
     'help': 'the architecture to build for'
   },
   'snapshot': {
-    'values': ['on', 'off'],
+    'values': ['on', 'off', 'nobuild'],
     'default': 'off',
     'help': 'build using snapshots for faster start-up'
   },
   'prof': {
     'values': ['on', 'off'],
     'default': 'off',
     'help': 'enable profiling of build target'
   },
   'library': {
     'values': ['static', 'shared'],
@@ skipping 72 matching lines @@
     if not env[name] in option['values']:
       message = ("Unknown %s value '%s'.  Possible values are (%s)." %
           (name, env[name], ", ".join(option['values'])))
       Abort(message)
 
 
 class BuildContext(object):
 
   def __init__(self, options, env_overrides, samples):
     self.library_targets = []
+    self.mksnapshot_targets = []
     self.cctest_targets = []
     self.sample_targets = []
     self.d8_targets = []
     self.options = options
     self.env_overrides = env_overrides
     self.samples = samples
-    self.use_snapshot = (options['snapshot'] == 'on')
+    self.use_snapshot = (options['snapshot'] != 'off')
+    self.build_snapshot = (options['snapshot'] == 'on')
     self.flags = None
 
   def AddRelevantFlags(self, initial, flags):
     result = initial.copy()
     self.AppendFlags(result, flags.get('all'))
     toolchain = self.options['toolchain']
     if toolchain in flags:
       self.AppendFlags(result, flags[toolchain].get('all'))
       for option in sorted(self.options.keys()):
         value = self.options[option]
@@ skipping 73 matching lines @@
   library_flags = context.AddRelevantFlags(os.environ, LIBRARY_FLAGS)
   v8_flags = context.AddRelevantFlags(library_flags, V8_EXTRA_FLAGS)
   jscre_flags = context.AddRelevantFlags(library_flags, JSCRE_EXTRA_FLAGS)
   dtoa_flags = context.AddRelevantFlags(library_flags, DTOA_EXTRA_FLAGS)
   cctest_flags = context.AddRelevantFlags(v8_flags, CCTEST_EXTRA_FLAGS)
   sample_flags = context.AddRelevantFlags(os.environ, SAMPLE_FLAGS)
   d8_flags = context.AddRelevantFlags(library_flags, D8_FLAGS)
 
   context.flags = {
     'v8': v8_flags,
+    'mksnapshot': v8_flags,
     'jscre': jscre_flags,
     'dtoa': dtoa_flags,
     'cctest': cctest_flags,
     'sample': sample_flags,
     'd8': d8_flags
   }
 
   target_id = mode
   suffix = SUFFIXES[target_id]
   library_name = 'v8' + suffix
   env['LIBRARY'] = library_name
 
   # Build the object files by invoking SCons recursively.  
-  (object_files, shell_files) = env.SConscript(
+  (object_files, shell_files, mksnapshot) = env.SConscript(
     join('src', 'SConscript'),
     build_dir=join('obj', target_id),
     exports='context',
     duplicate=False
   )
 
+  context.mksnapshot_targets.append(mksnapshot)
+
   # Link the object files into a library.
   env.Replace(**context.flags['v8'])
   context.ApplyEnvOverrides(env)
   if context.options['library'] == 'static':
     library = env.StaticLibrary(library_name, object_files)
   else:
     # There seems to be a glitch in the way scons decides where to put
     # PDB files when compiling using MSVC so we specify it manually.
     # This should not affect any other platforms.
     pdb_name = library_name + '.dll.pdb'
@@ skipping 34 matching lines @@
 def Build():
   opts = GetOptions()
   env = Environment(options=opts)
   Help(opts.GenerateHelpText(env))
   VerifyOptions(env)
   env_overrides = ParseEnvOverrides(env['env'])
 
   SourceSignatures(env['sourcesignatures'])
 
   libraries = []
+  mksnapshots = []
   cctests = []
   samples = []
   d8s = []
   modes = SplitList(env['mode'])
   for mode in modes:
     context = BuildSpecific(env.Copy(), mode, env_overrides)
     libraries += context.library_targets
+    mksnapshots += context.mksnapshot_targets
     cctests += context.cctest_targets
     samples += context.sample_targets
     d8s += context.d8_targets
 
   env.Alias('library', libraries)
+  env.Alias('mksnapshot', mksnapshots)
   env.Alias('cctests', cctests)
   env.Alias('sample', samples)
   env.Alias('d8', d8s)
 
   if env['sample']:
     env.Default('sample')
   else:
     env.Default('library')
 
 
 # We disable deprecation warnings because we need to be able to use
 # env.Copy without getting warnings for compatibility with older
 # version of scons.  Also, there's a bug in some revisions that
 # doesn't allow this flag to be set, so we swallow any exceptions.
 # Lovely.
 try:
   SetOption('warn', 'no-deprecated')
 except:
   pass
 
 
 Build()