多次尝试修复错误：链接器命令失败，退出代码为 1

Question

过去几天我一直在处理这个错误，但我真的被卡住了。我不断收到链接器命令错误，无法通过它。我在网上搜索并尝试了所有提示：检查重复文件、重新安装 pod、将活动架构设置为 NO、删除派生数据、清理很多次。

这是我得到的输出：

duplicate symbol _OBJC_IVAR_$_SessionPlayer._nextEvent in:
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayer.o
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayerViewController.o
duplicate symbol _OBJC_IVAR_$_SessionPlayer._visitors in:
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayer.o
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayerViewController.o
duplicate symbol _OBJC_IVAR_$_SessionPlayer._currentSessionTimeInMilliseconds in:
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayer.o
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayerViewController.o
duplicate symbol _OBJC_IVAR_$_SessionPlayer._systemTimeInMilliseconds in:
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayer.o
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayerViewController.o
duplicate symbol _OBJC_CLASS_$_SessionPlayer in:
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayer.o
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayerViewController.o
duplicate symbol _OBJC_METACLASS_$_SessionPlayer in:
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayer.o
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayerViewController.o
duplicate symbol _OBJC_IVAR_$_SessionPlayer._isPlaying in:
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayer.o
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayerViewController.o
duplicate symbol _OBJC_IVAR_$_SessionPlayer._useTiming in:
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayer.o
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayerViewController.o
duplicate symbol _OBJC_IVAR_$_SessionPlayer._delegate in:
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayer.o
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayerViewController.o
duplicate symbol _OBJC_IVAR_$_SessionPlayer._timeline in:
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayer.o
/Users/user1/Library/Developer/Xcode/DerivedData/***-APP-NAME-bahimtombyapwkcekphmmbaifpqx/Build/Intermediates/***-APP-NAME.build/Debug-iphonesimulator/***-APP-NAME.build/Objects-normal/x86_64/SessionPlayerViewController.o

ld: 10 duplicate symbols for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

真的不知道怎么办，很郁闷。

编辑：发现我的所有文件都被编译了两次，这可能是问题所在。

Answer 1

听起来您在目标的构建中包含了两次SessionPlayer.m 的源代码。根据某些 cmets，这可能是因为您通过 pod（这是您想要的）隐式引用文件，并且通过直接引用/包含（其中你不想要；这就是豆荚的用途）。尝试执行以下操作（我会尽量在文本中做到清晰，但如果您有任何问题，我可以附上屏幕截图）：

1. 在项目导航器窗格中，选择您的项目。
2. 在项目编辑器窗口中，选择您的应用目标（确保它不是 UnitTest/LogicTest 目标）。
3. 在项目编辑器窗口的顶部，选择“Build Phases”
4. 在主项目编辑器窗口中，现在应该有一个可扩展部分的列表，其中之一是“编译源（xxx 项）”，其中 xxx 是用于构建目标的源文件的数量。展开该部分。
5. 在搜索/过滤文本字段（项目编辑器的右上角，占位符文本显示“过滤”）中，输入“SessionPlayer”
6. 我怀疑您在此处明确包含了SessionPlayer.m，因此您应该在列表中至少看到一个实例。选择列表底部显示的“-”按钮将其删除。
7. 尝试重建并查看至少与SessionPlayer.m 相关的链接器错误是否消失。如果是这样，请对任何其他此类文件重复上述步骤。

希望这会有所帮助。