xcode8 coredata 创建 NSManagedObject Subclass 后生成四个文件，运行报错。

xcode8 coredata 创建 NSManagedObject Subclass 后，生成四个文件，如下图：



运行出错：

duplicate symbol OBJC_CLASS$_Student in:

/Users/bentudou/Library/Developer/Xcode/DerivedData/WorkSths-euluwhdcebmmukgypgabangnsbkb/Build/Intermediates/CoreDataTest.build/Debug-iphonesimulator/CoreDataTest.build/Objects-normal/x86_64/Student+CoreDataClass.o

duplicate symbol OBJC_METACLASS$_Student in:

/Users/bentudou/Library/Developer/Xcode/DerivedData/WorkSths-euluwhdcebmmukgypgabangnsbkb/Build/Intermediates/CoreDataTest.build/Debug-iphonesimulator/CoreDataTest.build/Objects-normal/x86_64/Student+CoreDataClass.o

ld: 2 duplicate symbols for architecture x86_64

clang: error: linker command failed with exit code 1 (use -v to see invocation)

解决办法：

1.先把创建的报错的四个文件删了

2.如图：



3.把Student+CoreDataClass.h和Student+CoreDataClass.m 文件更名为Student.h和Student.m，不要忘记把Student+CoreDataProperties.h 和Student+CoreDataProperties.m 中对Student+CoreDataClass.h的引用改成Student.h

然后运行，就好了。