我有一个奇怪的bug，其中一个块从我的登录方法是错误地在我的facebook签到功能的中间再次调用。这是很多的代码发布，但我的问题是我如何在xcode调试。我是否可以使用特定的工具来帮助跟踪从何处调用块?
下面是线程信息
#0 0x0017ca21 in __46-[FacebookRepo startLoginWithCompletionBlock:]_block_invoke at /Users/transformer/Projects/PictoriousApp/Pictorious/Core/FacebookRepo.m:183
#1 0x00440a96 in -[FBSession transitionAndCallHandlerWithState:error:token:expirationDate:shouldCache:loginType:] at /Users/jacl/src/release-trashme/ios-sdk/src/FBSession.m:1497
#2 0x004414fa in -[FBSession closeAndClearTokenInformation:] at /Users/jacl/src/release-trashme/ios-sdk/src/FBSession.m:1702
#3 0x0043d814 in -[FBSession closeAndClearTokenInformation] at /Users/jacl/src/release-trashme/ios-sdk/src/FBSession.m:417
#4 0x0017d1c4 in -[FacebookRepo startLogout] at /Users/transformer/Projects/PictoriousApp/Pictorious/Core/FacebookRepo.m:248
#5 0x00198dad in -[PictoriousSession startLogout] at /Users/transformer/Projects/PictoriousApp/Pictorious/Core/PictoriousSession.m:140
#6 0x00212841 in -[EditProfileViewController userLogOut] at /Users/transformer/Projects/PictoriousApp/Pictorious/Controllers/People/Profile/EditProfileViewController.m:293
使它看起来像
我也遇到过类似的问题。在我的例子中，它发生在我调用closeAndClearTokenInformation方法的时候。我已经解决了这个问题，只是在调用这个方法之前创建FBSession的新实例对象。
self.session = [[FBSession alloc] init];
[self.session closeAndClearTokenInformation];