迁移到Xcode 4.5后与Reachability相关的未定义符号

Question

我将Xcode项目从运行在Xcode 4.2上的Mac移动到运行Xcode 4.5的另一个mac后,我收到以下错误.

 "_SCError", referenced from:
      -[RKReachabilityObserver scheduleObserver] in libRestKit.a(RKReachabilityObserver.o)
      -[RKReachabilityObserver unscheduleObserver] in libRestKit.a(RKReachabilityObserver.o)
  "_SCErrorString", referenced from:
      -[RKReachabilityObserver scheduleObserver] in libRestKit.a(RKReachabilityObserver.o)
      -[RKReachabilityObserver unscheduleObserver] in libRestKit.a(RKReachabilityObserver.o)
  "_SCNetworkReachabilityCreateWithAddress", referenced from:
      +[Reachability reachabilityWithAddress:] in Reachability.o
      +[Reachability reachabilityWithAddress:] in test1ViewController.o
      -[RKReachabilityObserver initWithAddress:] in libRestKit.a(RKReachabilityObserver.o)
  "_SCNetworkReachabilityCreateWithName", referenced from:
      +[Reachability reachabilityWithHostName:] in Reachability.o
      +[Reachability reachabilityWithHostName:] in test1ViewController.o
      -[RKReachabilityObserver initWithHost:] in libRestKit.a(RKReachabilityObserver.o)
  "_SCNetworkReachabilityGetFlags", referenced from:
      -[Reachability connectionRequired] in Reachability.o
      -[Reachability currentReachabilityStatus] in Reachability.o
      -[Reachability connectionRequired] in test1ViewController.o
      -[Reachability currentReachabilityStatus] in test1ViewController.o
      -[RKReachabilityObserver getFlags] in libRestKit.a(RKReachabilityObserver.o)
  "_SCNetworkReachabilityScheduleWithRunLoop", referenced from:
      -[Reachability startNotifier] in Reachability.o
      -[Reachability startNotifier] in test1ViewController.o
  "_SCNetworkReachabilitySetCallback", referenced from:
      -[Reachability startNotifier] in Reachability.o
      -[Reachability startNotifier] in test1ViewController.o
      -[RKReachabilityObserver scheduleObserver] in libRestKit.a(RKReachabilityObserver.o)
  "_SCNetworkReachabilitySetDispatchQueue", referenced from:
      -[RKReachabilityObserver scheduleObserver] in libRestKit.a(RKReachabilityObserver.o)
      -[RKReachabilityObserver unscheduleObserver] in libRestKit.a(RKReachabilityObserver.o)
  "_SCNetworkReachabilityUnscheduleFromRunLoop", referenced from:
      -[Reachability stopNotifier] in Reachability.o
      -[Reachability stopNotifier] in test1ViewController.o
ld: symbol(s) not found for architecture i386

Answer 1

SCError,SCErrorString,...都来自SystemConfiguration.framework,因此在目标的"Link Binary With Libraries"设置中似乎缺少.

("未定义的符号......"链接器错误在很多情况下可以通过在XCode文档浏览器中查找没有前导下划线的符号来解决.在文档页面的顶部,您可以找到定义符号的框架.)