问题
I am facing issues with XCode snapshot. Actually I have Xcode 8.3.3, but I need to run Swift 4 project on it. Upgrading OSX and Xcode version is not an option for me.
I followed the accepted answer from here: Is it possible to compile Swift 4 on Xcode 8.x?
I downloaded Xcode snapshot (latest, 30th Dec release of toolchain) from https://swift.org/download/#snapshots
and made the required settings of toolchain. However, I am encountering a strange issue.
Again, to resolve this, I tried the accepted answer on link Could not build Objective-C module '_SwiftUIKitOverlayShims'
however, even this does not seem to work. Please suggest where I am going wrong.
来源：https://stackoverflow.com/questions/48073482/running-swift-4-code-on-xcode-8-3-issue-with-xcode-snapshot