Undefined symbols for architecture arm64:
"_OBJC_CLASS_$_NSManagedObjectContext", referenced from:
objc-class-ref in AppDelegate.o
"_OBJC_CLASS_$_NSPersistentStoreCoordinator", referenced from:
objc-class-ref in AppDelegate.o
"_OBJC_CLASS_$_NSManagedObjectModel", referenced from:
objc-class-ref in AppDelegate.o
"_NSSQLiteStoreType", referenced from:
-[AppDelegate persistentStoreCoordinator] in AppDelegate.o
ld: symbol(s) not found for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
linker command failed with exit code 1 (use -v to see invocation)
原文：http://www.cnblogs.com/royi123/p/5470784.html