链接器错误Unrar4iOS框架

Question

我已经添加了Unrar4iOS框架和下面的链接器错误。如何解决这个问题？

duplicate symbol __Z12CallbackProcjlll in:
    /Users/dmitryvlasenko/Library/Developer/Xcode/DerivedData/UnrealReader-cpvucqqjfnkeppcasgjdrwasaryu/Build/Intermediates/UnrealReader.build/Debug-iphonesimulator/UnrealReader.build/Objects-normal/i386/Unrar4iOS.o
    /Users/dmitryvlasenko/Desktop/UnrealReader/Unrar4iOS.framework/Unrar4iOS(Unrar4iOS.o)
duplicate symbol _OBJC_IVAR_$_Unrar4iOS.header in:
    /Users/dmitryvlasenko/Desktop/UnrealReader/Unrar4iOS.framework/Unrar4iOS(Unrar4iOS.o)
duplicate symbol _OBJC_IVAR_$_Unrar4iOS._rarFile in:
    /Users/dmitryvlasenko/Library/Developer/Xcode/DerivedData/UnrealReader-cpvucqqjfnkeppcasgjdrwasaryu/Build/Intermediates/UnrealReader.build/Debug-iphonesimulator/UnrealReader.build/Objects-normal/i386/Unrar4iOS.o
    /Users/dmitryvlasenko/Desktop/UnrealReader/Unrar4iOS.framework/Unrar4iOS(Unrar4iOS.o)
duplicate symbol _OBJC_IVAR_$_Unrar4iOS.filename in:
  /Users/dmitryvlasenko/Desktop/UnrealReader/Unrar4iOS.framework/Unrar4iOS(RARExtractException.o)
duplicate symbol _OBJC_EHTYPE_$_RARExtractException in:
    /Users/dmitryvlasenko/Library/Developer/Xcode/DerivedData/UnrealReader-cpvucqqjfnkeppcasgjdrwasaryu/Build/Intermediates/UnrealReader.build/Debug-iphonesimulator/UnrealReader.build/Objects-normal/i386/RARExtractException.o
    /Users/dmitryvlasenko/Desktop/UnrealReader/Unrar4iOS.framework/Unrar4iOS(RARExtractException.o)
ld: 12 duplicate symbols for architecture i386
clang: error: linker command failed with exit code 1 (use -v to see invocation)

Answer 1

该错误指示Unrar4iOS既是在Unrar4iOS.a中定义的，也是作为项目中的单个文件定义的。因此，请访问：

目标设置->构建阶段->将二进制文件与库链接并删除Unrar4iOS。

Answer 2

似乎你已经添加了两次相同的库，这就是为什么它显示"duplicate symbol __Z12CallbackProcjlll“的原因。

Answer 3

Unrar库是用C++编写的。如果您的项目中没有任何.mm文件，那么Xcode就不会链接到C++标准库，并且所有对C++的引用都无法链接。