ios sdk6.1 Link against the umbrella framework 'System.framework' instead.
尼玛,升级到xcode4.6的bug:ld:cannotlinkdirectlywith/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk/usr/lib/system/libcommonCrypto.dylib. Linkagainsttheum