我刚刚升级到xcode 4.0,我不能再部署到iPhone,我得到一个苹果Mach-O链接器错误,它仍然适用于模拟器。

    Ld /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Intermediates/iParcel.build/Debug-iphoneos/iParcel.build/Objects-normal/armv7/iParcel normal armv7
    cd /Users/yveswheeler/iParcel
    setenv IPHONEOS_DEPLOYMENT_TARGET 3.2
    setenv PATH "/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin:/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin"
    /Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/g++-4.2 -arch armv7 -isysroot /Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS4.3.sdk -L/Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Products/Debug-iphoneos -F/Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Products/Debug-iphoneos -filelist /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Intermediates/iParcel.build/Debug-iphoneos/iParcel.build/Objects-normal/armv7/iParcel.LinkFileList -dead_strip -all_load -ObjC -lxml2 -miphoneos-version-min=3.2 -framework UIKit -framework CoreGraphics -framework QuartzCore /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Products/Debug-iphoneos/libThree20.a /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Products/Debug-iphoneos/libThree20Core.a /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Products/Debug-iphoneos/libThree20Network.a /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Products/Debug-iphoneos/libThree20Style.a /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Products/Debug-iphoneos/libThree20UI.a /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Products/Debug-iphoneos/libThree20UICommon.a /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Products/Debug-iphoneos/libThree20UINavigator.a -framework AddressBook -lz.1.2.3 -framework Foundation -framework CFNetwork -framework MobileCoreServices -framework SystemConfiguration -framework MessageUI -framework AudioToolbox -o /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Intermediates/iParcel.build/Debug-iphoneos/iParcel.build/Objects-normal/armv7/iParcel

arm-apple-darwin10-g++-4.2.1: /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Products/Debug-iphoneos/libThree20.a: No such file or directory
arm-apple-darwin10-g++-4.2.1: /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Products/Debug-iphoneos/libThree20Core.a: No such file or directory
arm-apple-darwin10-g++-4.2.1: /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Products/Debug-iphoneos/libThree20Network.a: No such file or directory
arm-apple-darwin10-g++-4.2.1: /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Products/Debug-iphoneos/libThree20Style.a: No such file or directory
arm-apple-darwin10-g++-4.2.1: /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Products/Debug-iphoneos/libThree20UI.a: No such file or directory
arm-apple-darwin10-g++-4.2.1: /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Products/Debug-iphoneos/libThree20UICommon.a: No such file or directory
arm-apple-darwin10-g++-4.2.1: /Users/yveswheeler/Library/Developer/Xcode/DerivedData/iParcel-fkeqjcjcbbhjwhdssjptkdxzzzxh/Build/Products/Debug-iphoneos/libThree20UINavigator.a: No such file or directory
Command /Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/g++-4.2 failed with exit code 1

当前回答

对我来说,问题是我加载了相同的函数两次。从构建设置中移除-ObjC >链接>其他链接标志。

其他回答

使用CocoaPod,首先安装,然后打开工作区,而不是CocoaPod网站上指定的项目。

$ pod install

$ open YOUR_PROJECT_NAME.xcworkspace

当我得到这个错误时,我想分享另一个原因:

我在project Navigator(在Xcode 6.1.1中)中更改了项目名称,只需单击它,我的项目就无法编译。我把项目名称改回原来的名字,项目正在建设。非常非常奇怪,但我确实遇到过这种情况。我希望这些信息能有所帮助。

我遇到了同样的问题只是因为我在不同的类中有两个相同的常数。如果你导入的是。m文件而不是。h文件,你也会遇到这个问题

My problem was that in multiple class.m files I had created an NSString named TAG, and I had set the value of TAG to the String name of each class (Ex: NSString * TAG = HWGuiControl). I had done so that then it was easy to prepend my NSLog statements with the name of the class. (I have used this system in Android with great success, great for analyzing program flow 2 years later). Deploying to a device, this all works great. But when its time to create an Archive for distribution, apparently the linker cannot contend with the NSString named TAG appearing in multiple files. Modifying the name(s) of TAG to HWGTAG, etc, did the trick.

如果你用相同的名字定义了NSObject:

NSObject *notUniqueObj;

即使在2个不同的文件中(如果您在另一个文件中导入一个文件),它也会给您一个错误。给它们起不同的名字。