使用 IOS 构建重复符号答案

【问题标题】：Duplicate Symbols with IOS Build使用 IOS 构建重复符号
【发布时间】：2020-03-13 07:31:06
【问题描述】：

我正在尝试在 IOS 上运行我的 Flutter 应用程序（在 Android 上它可以正常运行），但是当我尝试运行它时出现以下错误：

 Launching lib/main.dart on iPhone 11 Pro Max in debug mode...
Xcode build done.                                           13,6s
Failed to build iOS app
Error output from Xcode build:
↳
    ** BUILD FAILED **
Xcode's output:
↳
    duplicate symbol '_OBJC_IVAR_$_GULZeroingWeakContainer._object' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULAppDelegateSwizzler 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULAppDelegateSwizzler.o
    duplicate symbol '_OBJC_CLASS_$_GULAppDelegateObserver' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULAppDelegateSwizzler 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULAppDelegateSwizzler.o
    duplicate symbol '_OBJC_METACLASS_$_GULAppDelegateObserver' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULAppDelegateSwizzler 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULAppDelegateSwizzler.o
    duplicate symbol '_OBJC_CLASS_$_GULZeroingWeakContainer' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULAppDelegateSwizzler 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULAppDelegateSwizzler.o
    duplicate symbol '_OBJC_METACLASS_$_GULZeroingWeakContainer' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULAppDelegateSwizzler 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULAppDelegateSwizzler.o
    duplicate symbol '_OBJC_CLASS_$_GULAppDelegateSwizzler' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULAppDelegateSwizzler 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULAppDelegateSwizzler.o
    duplicate symbol '_OBJC_METACLASS_$_GULAppDelegateSwizzler' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULAppDelegateSwizzler 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULAppDelegateSwizzler.o
    duplicate symbol '_OBJC_IVAR_$_GULAppDelegateObserver._isObserving' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULAppDelegateSwizzler 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULAppDelegateSwizzler.o
    duplicate symbol '_GULLogError' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULLogger 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULLogger.o
    duplicate symbol '_kGULNetworkTempDirectoryName' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkConstants 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkConstants.o
    duplicate symbol '_kGULNetworkHTTPStatusCodeUnavailable' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkConstants 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkConstants.o
    duplicate symbol '_kGULNetworkHTTPStatusCodeNotFound' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkConstants 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkConstants.o
    duplicate symbol '_kGULNetworkHTTPStatusCodeFound' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkConstants 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkConstants.o
    duplicate symbol '_kGULNetworkHTTPStatusCodeNotModified' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkConstants 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkConstants.o
    duplicate symbol '_kGULNetworkHTTPStatusCodeCannotAcceptTraffic' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkConstants 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkConstants.o
    duplicate symbol '_kGULNetworkHTTPStatusOK' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkConstants 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkConstants.o
    duplicate symbol '_OBJC_IVAR_$_GULNetworkURLSession._request' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession.o
    duplicate symbol '_OBJC_IVAR_$_GULNetworkURLSession._completionHandler' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession.o
    duplicate symbol '_OBJC_CLASS_$_GULNetworkURLSession' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession.o
    duplicate symbol '_OBJC_METACLASS_$_GULNetworkURLSession' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession.o
    duplicate symbol '_OBJC_IVAR_$_GULNetworkURLSession._URLSession' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession.o
    duplicate symbol '_OBJC_IVAR_$_GULNetworkURLSession._sessionConfig' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession.o
    duplicate symbol '_OBJC_IVAR_$_GULNetworkURLSession._loggerDelegate' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession.o
    duplicate symbol '_OBJC_IVAR_$_GULNetworkURLSession._backgroundNetworkEnabled' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession.o
    duplicate symbol '_OBJC_IVAR_$_GULNetworkURLSession._downloadedData' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession.o
    duplicate symbol '_OBJC_IVAR_$_GULNetworkURLSession._networkDirectoryURL' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession.o
    duplicate symbol '_OBJC_IVAR_$_GULNetworkURLSession._uploadingFileURL' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession.o
    duplicate symbol '_OBJC_IVAR_$_GULNetworkURLSession._sessionID' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNetworkURLSession.o
    duplicate symbol '_GULNSDataZlibRemainingBytesKey' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNSData+zlib 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNSData+zlib.o
    duplicate symbol '_GULNSDataZlibErrorKey' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNSData+zlib 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNSData+zlib.o
    duplicate symbol '_GULNSDataZlibErrorDomain' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNSData+zlib 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULNSData+zlib.o
    duplicate symbol '_OBJC_CLASS_$_GULReachabilityChecker' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULReachabilityChecker 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULReachabilityChecker.o
    duplicate symbol '_OBJC_METACLASS_$_GULReachabilityChecker' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULReachabilityChecker 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULReachabilityChecker.o
    duplicate symbol '_GULReachabilityStatusString' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULReachabilityChecker 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULReachabilityChecker.o
    duplicate symbol '_OBJC_IVAR_$_GULReachabilityChecker.reachability_' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULReachabilityChecker 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULReachabilityChecker.o
    duplicate symbol '_OBJC_IVAR_$_GULReachabilityChecker.host_' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULReachabilityChecker 2.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/GoogleUtilities.build/Objects-normal/x86_64/GULReachabilityChecker.o
    ld: 91 duplicate symbols for architecture x86_64
    clang: error: linker command failed with exit code 1 (use -v to see invocation)
    duplicate symbol '_pb_field_iter_next' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_common 3.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_common.o
    duplicate symbol '_pb_field_iter_begin' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_common 3.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_common.o
    duplicate symbol '_pb_field_iter_find' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_common 3.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_common.o
    duplicate symbol '_pb_decode_svarint' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_decode 3.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_decode.o
    duplicate symbol '_pb_decode_varint' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_decode 3.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_decode.o
    duplicate symbol '_pb_decode_noinit' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_decode 3.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_decode.o
    duplicate symbol '_pb_decode_delimited_noinit' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_decode 3.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_decode.o
    duplicate symbol '_pb_istream_from_buffer' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_decode 3.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_decode.o
    duplicate symbol '_pb_close_string_substream' in:
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_decode 3.o
        /Users/youni/Library/Developer/Xcode/DerivedData/Runner-bdpblnudevgtxmfuhxwqrsfeiwpe/Build/Intermediates.noindex/Pods.build/Debug-iphonesimulator/nanopb.build/Objects-normal/x86_64/pb_decode.o
    ld: 34 duplicate symbols for architecture x86_64
    clang: error: linker command failed with exit code 1 (use -v to see invocation)
    note: Using new build systemnote: Planning buildnote: Constructing build descriptionwarning: Mapping architecture armv7 to i386. Ensure that this target's Architectures and Valid Architectures build settings are configured correctly for the iOS Simulator platform. (in target 'image_picker' from project 'Pods')warning: Mapping architecture arm64 to x86_64. Ensure that this target's Architectures and Valid Architectures build settings are configured correctly for the iOS Simulator platform. (in target 'image_picker' from project 'Pods')
Could not build the application for the simulator.
Error launching application on iPhone 11 Pro Max.
Exited (sigterm)

目标平台：IOS 目标操作系统版本/浏览器：9.0 设备：Iphone 11 Pro Max

使用命令 Flutter 分析发现的问题只是一些未使用的导入或变量。颤振医生-v：

[✓] Flutter (Channel stable, v1.9.1+hotfix.5, on Mac OS X 10.14.6 18G103, locale it-IT)
    • Flutter version 1.9.1+hotfix.5 at /Users/youni/Desktop/YoUni/flutter
    • Framework revision 1aedbb1835 (4 weeks ago), 2019-10-17 08:37:27 -0700
    • Engine revision b863200c37
    • Dart version 2.5.0

[✗] Android toolchain - develop for Android devices
    ✗ Unable to locate Android SDK.
      Install Android Studio from: https://developer.android.com/studio/index.html
      On first launch it will assist you in installing the Android SDK components.
      (or visit https://flutter.dev/setup/#android-setup for detailed instructions).
      If the Android SDK has been installed to a custom location, set ANDROID_HOME to that location.
      You may also want to add it to your PATH environment variable.


[✓] Xcode - develop for iOS and macOS (Xcode 11.0)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 11.0, Build version 11A420a
    • CocoaPods version 1.6.0

[!] Android Studio (version 3.4)
    • Android Studio at /Applications/Android Studio.app/Contents
    ✗ Flutter plugin not installed; this adds Flutter specific functionality.
    ✗ Dart plugin not installed; this adds Dart specific functionality.
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1343-b01)

[✓] VS Code (version 1.39.2)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.6.0

[✓] Connected device (1 available)
    • iPhone 11 Pro Max • AC410C15-8848-486F-B911-2826D9BCD39F • ios • com.apple.CoreSimulator.SimRuntime.iOS-13-0 (simulator)

! Doctor found issues in 2 categories.

我将 image_picker 插件升级到最新版本，应用程序第一次正常运行时，第二次出现此错误。所以我不明白错误是由这个插件还是由其他东西引起的。如果我错过了或者您需要一些其他信息，请告诉我。
附言。由于字符限制，我不得不删除 Xcode 输出的一些行，如果您需要完整的日志，请告诉我。

【问题讨论】：

当我得到那些奇怪的东西时，有时执行“flutter clean”会有所帮助。以防万一你还没有尝试过。

标签： ios xcode flutter dart visual-studio-code

【解决方案1】：

当项目位于 iCloud 目录中时，可能会发生这种情况，从而导致文件重复。我看到了两种解决方法：

1- 从根项目中删除重复文件。 始终先运行不带 -delete 的 find 命令，以确保您没有删除不需要的文件

find . -name \*\ 2.\*
find . -name \*\ 2.\* -delete
find . -name \*\ 3.\*
find . -name \*\ 3.\* -delete
flutter clean
flutter run

2- 使用以下命令清理/重新安装 pod（在颤振项目根目录上）

cd ios
pod deintegrate
cd ..
flutter clean
flutter run

最终的解决方案是从 iCloud 目录中删除颤振项目。但是，我也在 iCloud 目录中使用它，以确保备份我的“gitignored”文件。我也在寻找更好的解决方案。

让我知道它是否有效。

【讨论】：

【解决方案2】：

当flutter package get 由于连接问题或类似问题而无法完成或陷入死锁时，有时会发生这种情况。

以下命令将执行临时修复。

  cd ios/
  pod cache clean --all
  pod deintegrate --verbose
  pod setup --verbose
  pod install --verbose

希望对你有帮助！

【讨论】：

【解决方案3】：

这对我有用 - 对于报告警告的目标，将“有效架构”设置更改为：

$(VALID_ARCHS)
x86_64

您是否也可以尝试将部署目标更改为例如 13.2？我希望这会有所帮助

【讨论】：

很抱歉，但对我来说没有用。我还尝试删除 DeriveData 文件夹并运行 flutter clean 但没有任何效果。顺便谢谢你的回答。
作为 IOS 部署目标，最高版本为 13.0，但没有任何变化。

【解决方案4】：

直到我发现我有一个包含多个文件副本的 flutter/.pub-cache 目录，这些文件显然每次都被复制到 ~/Library/Developer/Xcode/DerivedData/ 之前，什么都没有。

删除 .pub-cache 目录和所有现有的 DerivedData 目录后，我的构建再次开始工作。

我的开发文件夹在 iCloud 上，也许这与它开始的原因有关。奇怪的是 .pub-cache 目录还没有（还）回来，我需要睁大眼睛看看它。

【讨论】：