表題の件、、、
概要
表題のエラーが出ました。最近よくみます。
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Cycle inside "YOUR_APPS"; building could produce unreliable results. This usually can be resolved by moving the target's Headers build phase before Compile Sources.
詳細ログ
:-1: Cycle inside yamadatakayuki; building could produce unreliable results. This usually can be resolved by moving the target's Headers build phase before Compile Sources.
> Cycle details:
> → That command depends on command in Target 'sevens': script phase “[CP] Embed Pods Frameworks”
> → That command depends on command in Target 'sevens': script phase “Run Script”
> ○ Target 'yamadatakayuki': Ditto /Users/yamadatakayuki/Library/Developer/Xcode/DerivedData/yamadatakayuki-ffpcyajugyacpogctglgosyzefml/Build/Intermediates.noindex/yamadatakayuki.build/Debug-iphonesimulator/yamadatakayuki.build/DerivedSources/yamadatakayuki-Swift.h /Users/yamadatakayuki/Library/Developer/Xcode/DerivedData/yamadatakayuki-ffpcyajugyacpogctglgosyzefml/Build/Intermediates.noindex/yamadatakayuki.build/Debug-iphonesimulator/yamadatakayuki.build/Objects-normal/x86_64/yamadatakayuki-Swift.h
> ○ Target 'yamadatakayuki' has compile command for Swift source files
なぜこうなるかの理由（概要）
ビルドするときのサイクルの順番があまりよろしくないぜ〜みたいな感じです。
つまりビルドの順番なので
resolve
Xcode -> target -> Build Phasesの下記項目の順番を変更します。
before
after
これで解決します。