没有遗留构建系统 如果你有这样的Podfile

def shared_pods
  pod 'X'
end

target 'A' do
  shared_pods
end

target 'B' do
  shared_pods
end

B也依赖于A然后像这样把B移到A

 target 'A' do

   shared_pods

   target 'B' do
     inherit! :search_paths
   end
 end

在开始之前，请注意我的项目使用Carthage作为依赖管理器。

这里没有一个现有的答案能解决我的问题。为我解决这个问题的方法如下。

First, I noticed that the build error pointed out one framework in particular. Next I filtered App Target > Build Phases for that framework. I noticed that that framework was present in both "Link Binary With Libraries" and "Embed Frameworks". Noting that none of the frameworks listed under "Embed Frameworks" were ones managed by Carthage I removed the framework in question from "Embed Frameworks". I then re-built my project and everything works fine including the functionality enabled by the framework in question.

这是我的错误信息:

error: Multiple commands produce '/Users/runner/Library/Developer/Xcode/DerivedData/slapshot-ios-bpixgzdbgfcmofhguehgrznwbjxl/Build/Intermediates.noindex/ArchiveIntermediates/slapshot-ios-example/IntermediateBuildFilesPath/UninstalledProducts/iphoneos/Introspect.framework'
    note: Target 'Introspect-dynamic' (project 'Pods') has create directory command with output '/Users/runner/Library/Developer/Xcode/DerivedData/slapshot-ios-bpixgzdbgfcmofhguehgrznwbjxl/Build/Intermediates.noindex/ArchiveIntermediates/slapshot-ios-example/IntermediateBuildFilesPath/UninstalledProducts/iphoneos/Introspect.framework'
    note: Target 'Introspect-static' (project 'Pods') has create directory command with output '/Users/runner/Library/Developer/Xcode/DerivedData/slapshot-ios-bpixgzdbgfcmofhguehgrznwbjxl/Build/Intermediates.noindex/ArchiveIntermediates/slapshot-ios-example/IntermediateBuildFilesPath/UninstalledProducts/iphoneos/Introspect.framework'

我必须添加:linkage =>:static到我的所有目标，而不仅仅是其中的一些，在运行pod deintegrate/pod install之前(归功于这个答案)。

在我的例子中，我添加了GoogleService-Info。plist文件两次失望地到我的Firebase项目。

我先删除添加的GoogleService-Info。Plist，问题解决了。

在我们的例子中，我们只是清理了“Copy Bundle Resources”中的任何碎片，只留下最小的项目。

这个答案已经弃用了——Xcode 12已经弃用了遗留构建系统，它将在进一步的版本中被移除

我使用的是Xcode 11.4 不能构建旧项目

Xcode => File => Project Settings => Build System => Legacy Build System