如果引发异常，则所有函数都将退回到该点在其中找到匹配类型 catch 的 try ... catch 块。如果未从try块内调用您的函数，则程序将以未处理的异常退出。

If you throw an exception, all functions will be exited back to the point where it finds a try...catch block with a matching catch type. If your function isn't called from within a try block, the program will exit with an unhandled exception.

签出 https://isocpp.org/wiki/faq/exceptions 了解更多信息。