Add support for Mac OS X 64bit builds with GYP

tools/gyp/v8.gyp

 # Copyright 2012 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 41 matching lines @@
               'dependencies': ['v8_base', 'v8_nosnapshot'],
             }],
             ['component=="shared_library"', {
               'type': '<(component)',
               'sources': [
                 # Note: on non-Windows we still build this file so that gyp
                 # has some sources to link into the component.
                 '../../src/v8dll-main.cc',
               ],
               'conditions': [
+                ['OS=="mac"', {
+                  'xcode_settings': {
+                    'OTHER_LDFLAGS': ['-dynamiclib', '-all_load']
+                  },
+                }],
                 ['OS=="win"', {
                   'defines': [
                     'BUILDING_V8_SHARED',
                   ],
                   'direct_dependent_settings': {
                     'defines': [
                       'USING_V8_SHARED',
                     ],
                   },
                 }, {
@@ skipping 928 matching lines @@
             }],
           ],
           'dependencies': [
             'v8'
           ],
         },
       ],
     }],
   ],
 }