描述：今天升级xcode（v11.3 -> v11.4.1），编译项目，报错：
Building for iOS Simulator, but the linked library 'xxx.a' was built for iOS.Building for iOS, but the linked library 'xxx-iPhonesimulator.a' was built for iOS Simulator.
解决办法
Xcode -> File -> Workspace Settings -> Build System -> Legacy Build System