iOS Clang error-Xcode5

Question

I've seen several posts on google and stackoverflow related to this error, I've read all of them but still fetching the problem , I will be glad for a solution. Here is the error mesage I recieve when compiling ..

duplicate symbol _OBJC_IVAR_$_crc_assess_q1.answers in:
    /Users/somefolder/Library/Developer/Xcode/DerivedData/CRC-cwtaapkjcvsdiaddtmdolovjtsgf/Build/Intermediates/CRC.build/Debug-iphonesimulator/CRC.build/Objects-normal/i386/crc_assess_q2.o
    /Users/somefolder/Library/Developer/Xcode/DerivedData/CRC-cwtaapkjcvsdiaddtmdolovjtsgf/Build/Intermediates/CRC.build/Debug-iphonesimulator/CRC.build/Objects-normal/i386/crc_assess_q1.o
duplicate symbol _OBJC_IVAR_$_crc_assess_q1._assessQuestion1Label in:
    /Users/somefolder/Library/Developer/Xcode/DerivedData/CRC-cwtaapkjcvsdiaddtmdolovjtsgf/Build/Intermediates/CRC.build/Debug-iphonesimulator/CRC.build/Objects-normal/i386/crc_assess_q2.o
    /Users/somefolder/Library/Developer/Xcode/DerivedData/CRC-cwtaapkjcvsdiaddtmdolovjtsgf/Build/Intermediates/CRC.build/Debug-iphonesimulator/CRC.build/Objects-normal/i386/crc_assess_q1.o
duplicate symbol _OBJC_IVAR_$_crc_assess_q1._answer1Table in:
    /Users/somefolder/Library/Developer/Xcode/DerivedData/CRC-cwtaapkjcvsdiaddtmdolovjtsgf/Build/Intermediates/CRC.build/Debug-iphonesimulator/CRC.build/Objects-normal/i386/crc_assess_q2.o
    /Users/somefolder/Library/Developer/Xcode/DerivedData/CRC-cwtaapkjcvsdiaddtmdolovjtsgf/Build/Intermediates/CRC.build/Debug-iphonesimulator/CRC.build/Objects-normal/i386/crc_assess_q1.o
duplicate symbol _OBJC_CLASS_$_crc_assess_q1 in:
    /Users/somefolder/Library/Developer/Xcode/DerivedData/CRC-cwtaapkjcvsdiaddtmdolovjtsgf/Build/Intermediates/CRC.build/Debug-iphonesimulator/CRC.build/Objects-normal/i386/crc_assess_q2.o
    /Users/somefolder/Library/Developer/Xcode/DerivedData/CRC-cwtaapkjcvsdiaddtmdolovjtsgf/Build/Intermediates/CRC.build/Debug-iphonesimulator/CRC.build/Objects-normal/i386/crc_assess_q1.o
duplicate symbol _OBJC_METACLASS_$_crc_assess_q1 in:
    /Users/somefolder/Library/Developer/Xcode/DerivedData/CRC-cwtaapkjcvsdiaddtmdolovjtsgf/Build/Intermediates/CRC.build/Debug-iphonesimulator/CRC.build/Objects-normal/i386/crc_assess_q2.o
    /Users/somefolder/Library/Developer/Xcode/DerivedData/CRC-cwtaapkjcvsdiaddtmdolovjtsgf/Build/Intermediates/CRC.build/Debug-iphonesimulator/CRC.build/Objects-normal/i386/crc_assess_q1.o
ld: 5 duplicate symbols for architecture i386

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

Answer 1

I am assuming that you have duplicate files in your Project Directory, check
Build Phases>Compile Sources of you project and see wether more than two file with same name is there or not