ubuntu刚刚下载vscode并且配置c++完成后出现以下错误：
Stopping due to fatal error: NullReferenceException: Object reference not set to an instance of an object
问题的解决办法：https://github.com/Microsoft/vscode-cpptools/issues/2922
Workaround: use “externalConsole”: false in launch.json
即把launch.json中的externalConsole 改为 false