我试图做一个应用程序阅读pdf使用PDF工具包在Xcode 4.3,但它给我以下错误
ld: duplicate symbol _OBJC_MetaCLASS_$_OverlayManager in /Users/dt4it/Library/Developer/Xcode/DerivedData/MyPdf4-bmkjglhhvneluqcbwpceiqjvdcmq/Build/Intermediates/MyPdf4.build/Debug-iphonesimulator/MyPdf4.build/Objects-normal/i386/OverlayManager-D0866CFD31A05E68.o and /Users/dt4it/Library/Developer/Xcode/DerivedData/MyPdf4-bmkjglhhvneluqcbwpceiqjvdcmq/Build/Intermediates/MyPdf4.build/Debug-iphonesimulator/MyPdf4.build/Objects-normal/i386/OverlayManager-B31AE7412100AF6D.o for architecture i386 Command /Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang Failed with exit code 1
任何帮助请??