安裝了xcode10之后，運行老項目報錯：
提示有重復文件：

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:-1: Multiple commands produce '/Users/huishoubao/Library/Developer/Xcode/DerivedData/Customer-dogpkovoxdyzcfezweifcnjtfjgc/Build/Products/Debug-iphonesimulator/TesseractOCRiOS/config_auto.h':
1) Target 'TesseractOCRiOS' (project 'Pods') has copy command from '/Users/huishoubao/Desktop/iOS2B/Customer/Customer/Pods/TesseractOCRiOS/TesseractOCR/include/leptonica/config_auto.h' to '/Users/huishoubao/Library/Developer/Xcode/DerivedData/Customer-dogpkovoxdyzcfezweifcnjtfjgc/Build/Products/Debug-iphonesimulator/TesseractOCRiOS/config_auto.h'
2) Target 'TesseractOCRiOS' (project 'Pods') has copy command from '/Users/huishoubao/Desktop/iOS2B/Customer/Customer/Pods/TesseractOCRiOS/TesseractOCR/include/tesseract/config_auto.h' to '/Users/huishoubao/Library/Developer/Xcode/DerivedData/Customer-dogpkovoxdyzcfezweifcnjtfjgc/Build/Products/Debug-iphonesimulator/TesseractOCRiOS/config_auto.h'

主要是和Xcode10的更新點有關系。這邊著重提及下與本問題相關的一個更新點。

Build System

Again, Xcode 10 uses a new build system. The new build system provides improved reliability and build performance, and it catches project configuration problems that the legacy build system does not.
The legacy build system is still available in Xcode 10. To use the legacy build system, select it in the File > Project/Workspace Settings sheet. Projects configured to use the legacy build system will display an orange hammer icon in the Activity View.

簡單而言，Xcode10使用了一個的新創建系統，比之前的提供更好的可靠性與創建性能，而且可以獲取項目配置問題（默認設置新創建系統）

在蘋果文檔中，提及Xcode10中的關于舊項目New Build System更改適配中提及到以下兩點

The new build system has stricter checks for cycles between elements in the build in order to prevent unnecessary rebuilds.

It is an error for any individual file in the build to be produced by more than one build command. For example, if two targets each declare the same output file from a shell script phase, factor out the declaration of the output file into a single target.

New Build System會對構建中的元素循環進行嚴格的檢查，避免不必要的重建，這個也是錯誤出現的原因。

錯誤發生的兩種普遍形式：

1、info.plist 和.png

錯誤信息

Multiple commands produce '/Users/tjsoft/Library/Developer/Xcode/DerivedData/TYKYTwoLearnOneDo-amcfzswumxdotlgjwdslugmywxch/Build/Products/Debug-iphoneos/TYKYTwoLearnOneDo.app/Info.plist':
1) Target 'TYKYTwoLearnOneDo' (project 'TYKYTwoLearnOneDo') has copy command from '/Users/tjsoft/TYKY /黨建/黔紀/QianJiDangJian_iOS/TYKYTwoLearnOneDo/Info.plist' to '/Users/tjsoft/Library/Developer/Xcode/DerivedData/TYKYTwoLearnOneDo-amcfzswumxdotlgjwdslugmywxch/Build/Products/Debug-iphoneos/TYKYTwoLearnOneDo.app/Info.plist'
2) Target 'TYKYTwoLearnOneDo' (project 'TYKYTwoLearnOneDo') has process command with output '/Users/tjsoft/Library/Developer/Xcode/DerivedData/TYKYTwoLearnOneDo-amcfzswumxdotlgjwdslugmywxch/Build/Products/Debug-iphoneos/TYKYTwoLearnOneDo.app/Info.plist'

2、Copy Pods Resources

錯誤信息

Multiple commands produce '/Users/tjsoft/Library/Developer/Xcode/DerivedData/TYKYTwoLearnOneDo-amcfzswumxdotlgjwdslugmywxch/Build/Products/Debug-iphoneos/TYKYTwoLearnOneDo.app':
1) Target 'TYKYTwoLearnOneDo' has create directory command with output '/Users/tjsoft/Library/Developer/Xcode/DerivedData/TYKYTwoLearnOneDo-amcfzswumxdotlgjwdslugmywxch/Build/Products/Debug-iphoneos/TYKYTwoLearnOneDo.app'
2) That command depends on command in Target 'TYKYTwoLearnOneDo': script phase “[CP] Copy Pods Resources”

解決方法可以有兩種，

方案一：是不使用New Build System，修改了xcode的配置暫時解決了編譯報錯的問題。

在File > Project/Workspace Settings中的Share Project/Workspace Settings 里build system 將New Build System(Default)切換成Legacy build system。

設置build system.png

方案二：是根據出錯信息，在新創建系統模式下，去除多余的引用重建。

Info.plist

在 target -> Build phase > Copy Bundle Resource 中找到info.plist，移除

刪除相應的重復文件.png

Copy Pods Resources

在 target -> Build phase > Copy Pods Resources -> Output Files，移除${TARGET_BUILD_DIR}/${UNLOCALIZED_RESOURCES_FOLDER_PATH}

刪除copy Pod文件.png

第三方SDK內重復的文件

是在pod進去的文件中，重命名的文件，打開查看了，發現內容不一樣。

重復文件.png

因為是第三方sdk里面的，我不確定刪除哪個，就更改了build system ，將New Build System(Default)切換成Legacy build system。

參考鏈接：http://www.lxweimin.com/p/fdb1421f3c8b