lib/libz.1.2.5.dylib, missing required architecture armv7 in file error

错误log：

Ld /Users/wbw1985/Library/Developer/Xcode/DerivedData/Single_View_One-cudhbnbatgdjmoaeautlrzpyfcto/Build/Products/Debug-iphoneos/Single_View_One.app/Single_View_One normal armv7

    cd /Users/wbw1985/ios/test_for_me/Single_View_One
    setenv IPHONEOS_DEPLOYMENT_TARGET 5.1
    setenv PATH "/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin:/Applications/Xcode.app/Contents/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin"
    /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang -arch armv7 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.1.sdk -L/Users/wbw1985/Library/Developer/Xcode/DerivedData/Single_View_One-cudhbnbatgdjmoaeautlrzpyfcto/Build/Products/Debug-iphoneos -L/Users/wbw1985/ios/test_for_me/Single_View_One/Single_View_One/lib -F/Users/wbw1985/Library/Developer/Xcode/DerivedData/Single_View_One-cudhbnbatgdjmoaeautlrzpyfcto/Build/Products/Debug-iphoneos -F/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.1.sdk/Developer/Library/Frameworks -F/Applications/Xcode.app/Contents/Developer/Library/Frameworks -filelist /Users/wbw1985/Library/Developer/Xcode/DerivedData/Single_View_One-cudhbnbatgdjmoaeautlrzpyfcto/Build/Intermediates/Single_View_One.build/Debug-iphoneos/Single_View_One.build/Objects-normal/armv7/Single_View_One.LinkFileList -dead_strip -lxml2 -miphoneos-version-min=5.1 -framework QuartzCore -lz.1.2.5 -framework CoreGraphics -framework MobileCoreServices -framework SystemConfiguration -framework CFNetwork -framework UIKit -framework Foundation -o /Users/wbw1985/Library/Developer/Xcode/DerivedData/Single_View_One-cudhbnbatgdjmoaeautlrzpyfcto/Build/Products/Debug-iphoneos/Single_View_One.app/Single_View_One

ld: warning: ignoring file /Users/wbw1985/ios/test_for_me/Single_View_One/Single_View_One/lib/libz.1.2.5.dylib, missing required architecture armv7 in file
Undefined symbols for architecture armv7:
  "_inflateEnd", referenced from:
      -[ASIDataDecompressor closeStream] in ASIDataDecompressor.o
  "_inflate", referenced from:
      -[ASIDataDecompressor uncompressBytes:length:error:] in ASIDataDecompressor.o
  "_deflateEnd", referenced from:
      -[ASIDataCompressor closeStream] in ASIDataCompressor.o
  "_inflateInit2_", referenced from:
      -[ASIDataDecompressor setupStream] in ASIDataDecompressor.o
  "_deflate", referenced from:
      -[ASIDataCompressor compressBytes:length:error:shouldFinish:] in ASIDataCompressor.o
  "_deflateInit2_", referenced from:
      -[ASIDataCompressor setupStream] in ASIDataCompressor.o
ld: symbol(s) not found for architecture armv7
clang: error: linker command failed with exit code 1 (use -v to see invocation)

原来是因为我把lib/libz.1.2.5.dylib放在了工程目录，在工程目录删除后clen，编译成功。