苹果早在 Xcode 8中 就废弃了libstdc++, 给了开发者两年时间过渡, 如今从Xcode 10中已不再支持. 在Build Phases > Link Binary With Libraries 中已经搜不到libstdc++的库了
将缺少的库加入xcode10/11的相应目录。缺失的库可以在老版xcode目录中找
模拟器需要的tbd:
libstdc++.6.0.9.tbd
路径:/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk/usr/lib/
真机需要的tbd:
libstdc++.6.0.9.tbd
路径:/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk/usr/lib/
dylib :
libstdc++.6.0.9.dylib
(两个,包括快捷方式) xcode11之前路径:/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/Library/CoreSimulator/Profiles/Runtimes/iOS.simruntime/Contents/Resources/RuntimeRoot/usr/lib/
xcode11路径:/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Library/Developer/CoreSimulator/Profiles/Runtimes/iOS.simruntime/Contents/Resources/RuntimeRoot/usr/lib