old_contents: {
    'targets': [
      {
        'target_name': 'komachan',
        'sources': [
          'src/komachan.cc',
          'src/game.cc',
          'src/board.cc',
          'src/search.cc',
          'src/io.cc'
        ],
        'include_dirs': [
          "<!(node -e \"require('nan')\")"
        ],
        'conditions': [
          [ 'OS=="mac"', {
            'xcode_settings': {
              'OTHER_CPLUSPLUSFLAGS' : ['-stdlib=libc++', '-O3'],
              'MACOSX_DEPLOYMENT_TARGET': '10.7',
              },
            }
          ],
        ],
        'cflags' : [
          '-std=c++11', '-O3'
        ],
      }
    ]
  }
  
new_contents: {
    'make_global_settings': [
      ['CXX','/usr/bin/clang++'],
      ['LINK','/usr/bin/clang++'],
    ],
    'targets': [
      {
        'target_name': 'komachan',
        'sources': [
          'src/komachan.cc',
          'src/game.cc',
          'src/board.cc',
          'src/search.cc',
          'src/io.cc'
        ],
        'include_dirs': [
          "<!(node -e \"require('nan')\")"
        ],
        'conditions': [
          [ 'OS=="mac"', {
            'xcode_settings': {
              'OTHER_CPLUSPLUSFLAGS' : ['-stdlib=libc++', '-O3'],
              'MACOSX_DEPLOYMENT_TARGET': '10.7',
              },
            }
          ],
        ],
        'cflags' : [
          '-std=c++11', '-O3'
        ],
      }
    ]
  }
  
subject: improve binding.gyp to use clang