old_contents: {
    "targets": [
      {
        "target_name": "lmdb",
        "type": "static_library",
        "standalone_static_library": 1,
        "defines": [
        ],
        "sources": [
          "lmdb/midl.c",
          "lmdb/mdb.c",
        ],
        "conditions": [
          [
            "OS == 'win'", {
              "msvs_settings": {
                "VCCLCompilerTool": {
                  "EnableFunctionLevelLinking": "true",
                  "DisableSpecificWarnings": [ "4024", "4047", "4146", "4244", "4267", "4996" ]
                }
              }
            }
          ]
        ]
      }
    ]
  }
new_contents: {
    "targets": [
      {
        "target_name": "lmdb",
        "type": "static_library",
        "standalone_static_library": 1,
        "defines": [
        ],
        "sources": [
          "lmdb/midl.c",
          "lmdb/mdb.c",
        ],
        "conditions": [
          [
            "OS == 'win'", {
              "msvs_settings": {
                "VCCLCompilerTool": {
                  "EnableFunctionLevelLinking": "true",
                  "DisableSpecificWarnings": [ "4024", "4047", "4146", "4244", "4267", "4996" ]
                }
              }
            }
          ],
          [
            "OS == 'mac'", {
              "xcode_settings": {
                "WARNING_CFLAGS": [
                  "-Wno-format-extra-args"
                ]
              }
            }
          ]
        ]
      }
    ]
  }
subject: fix warning on mac.