old_contents: {
    'targets': [
      {
        'target_name': 'magic',
        'sources': [
          'src/binding.cc',
        ],
        'include_dirs': [
          'deps/libmagic/src',
          "<!(node -e \"require('nan')\")"
        ],
        'cflags!': [ '-O2' ],
        'cflags+': [ '-O3' ],
        'cflags_cc!': [ '-O2' ],
        'cflags_cc+': [ '-O3' ],
        'cflags_c!': [ '-O2' ],
        'cflags_c+': [ '-O3' ],
        'dependencies': [
          'deps/libmagic/libmagic.gyp:libmagic',
        ],
      },
    ],
  }
new_contents: {
    'targets': [
      {
        'target_name': 'magic',
        'sources': [
          'src/binding.cc',
        ],
        'include_dirs': [
          'deps/libmagic/src',
          "<!(node -e \"require('nan')\")"
        ],
        'cflags!': [ '-O2' ],
        'cflags+': [ '-O3' ],
        'cflags_cc!': [ '-O2' ],
        'cflags_cc+': [ '-O3' ],
        'cflags_c!': [ '-O2' ],
        'cflags_c+': [ '-O3' ],
        'dependencies': [
          'deps/libmagic/libmagic.gyp:libmagic',
        ],
        'conditions': [
          ['OS=="mac"', {
            'xcode_settings': {
              'MACOSX_DEPLOYMENT_TARGET': '10.7',
              'GCC_VERSION': 'com.apple.compilers.llvm.clang.1_0',
              'CLANG_CXX_LANGUAGE_STANDARD': 'gnu++1y',  # -std=gnu++1y
              'CLANG_CXX_LIBRARY': 'libc++',
            }
          }],
        ],
      },
    ],
  }
  
subject: fix build on macOS Mojave with XCode 10