Vanishing swiftdoc, swiftsourceinfo, swift module files

In prep for a push this evening did the usual clean and rebuild. But now I'm getting errors that it can't find files with .swiftdoc, swiftsourceinfo, and swiftmodule files. The few postings I can find about that said that reinstalling xcode fixed it, well , not i my case. Any ideas short of reconstructing the entire project from scratch?

Vanishing swiftdoc, swiftsourceinfo, swift module files
 
 
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