IOS Bugs5 linker command failed with exit code 1 (use -v to see invocation)

Ld /Users/Rubert/Library/Developer/Xcode/DerivedData/OC_Language-emftyzftyvhdpuaxipddjmpnpvox/Build/Products/Debug/OC_Language normal x86_64

    cd /Users/Rubert/IOS/iworkspace/OC_Language

    export MACOSX_DEPLOYMENT_TARGET=10.10

    /Applications/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang -arch x86_64 -isysroot /Applications/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk -L/Users/Rubert/Library/Developer/Xcode/DerivedData/OC_Language-emftyzftyvhdpuaxipddjmpnpvox/Build/Products/Debug -F/Users/Rubert/Library/Developer/Xcode/DerivedData/OC_Language-emftyzftyvhdpuaxipddjmpnpvox/Build/Products/Debug -filelist /Users/Rubert/Library/Developer/Xcode/DerivedData/OC_Language-emftyzftyvhdpuaxipddjmpnpvox/Build/Intermediates/OC_Language.build/Debug/OC_Language.build/Objects-normal/x86_64/OC_Language.LinkFileList -mmacosx-version-min=10.10 -fobjc-arc -fobjc-link-runtime -Xlinker -dependency_info -Xlinker /Users/Rubert/Library/Developer/Xcode/DerivedData/OC_Language-emftyzftyvhdpuaxipddjmpnpvox/Build/Intermediates/OC_Language.build/Debug/OC_Language.build/Objects-normal/x86_64/OC_Language_dependency_info.dat -o /Users/Rubert/Library/Developer/Xcode/DerivedData/OC_Language-emftyzftyvhdpuaxipddjmpnpvox/Build/Products/Debug/OC_Language

 

Undefined symbols for architecture x86_64:

  "_OBJC_CLASS_$_Persion", referenced from:

      objc-class-ref in main.o

ld: symbol(s) not found for architecture x86_64

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

http://blog.csdn.net/hengshujiyi/article/details/21182813(must be select Target Membership)