我刚刚切换到xCode 5 Preview，对现有项目之一收到了很多警告。
ld: warning: linking ObjC for iOS Simulator, but object file (/Projects/iOs/WWS/SVN/iOS/WWS/WWS/ExtFrameworks/GoogleAdMobAdsSdkiOS/libGoogleAdMobAds.a(GADSearchRequestPrivate.o)) was compiled for MacOSX
ld: warning: linking ObjC for iOS Simulator, but object file (/Projects/iOs/WWS/SVN/iOS/WWS/WWS/ExtFrameworks/GoogleAdMobAdsSdkiOS/libGoogleAdMobAds.a(GADCachedFile.o)) was compiled for MacOSX
ld: warning: linking ObjC for iOS Simulator, but object file (/Projects/iOs/WWS/SVN/iOS/WWS/WWS/ExtFrameworks/GoogleAdMobAdsSdkiOS/libGoogleAdMobAds.a(GADNetworkChecker.o)) was compiled for MacOSX
ld: warning: linking ObjC for iOS Simulator, but object file (/Projects/iOs/WWS/SVN/iOS/WWS/WWS/ExtFrameworks/GoogleAdMobAdsSdkiOS/libGoogleAdMobAds.a(GADTiming.o)) was compiled for MacOSX
ld: warning: linking ObjC for iOS Simulator, but object file (/Projects/iOs/WWS/SVN/iOS/WWS/WWS/ExtFrameworks/GoogleAdMobAdsSdkiOS/libGoogleAdMobAds.a(GADTimingManager.o)) was compiled for MacOSX
ld: warning: linking ObjC for iOS Simulator, but object file (/Projects/iOs/WWS/SVN/iOS/WWS/WWS/ExtFrameworks/GoogleAdMobAdsSdkiOS/libGoogleAdMobAds.a(GADRequestError.o)) was compiled for MacOSX