On Apr 4, 2019, at 4:08 PM, r-sig-mac-request at r-project.org wrote: thanks, but can you give some details? I'm on a Mojave system and don't see any issues - this will likely depend on your Xcode installation. Does it mean some Xcode version is lacking headers? Which version, how did you install it?
fwiw, searching turns up others mentioning the issue. https://github.com/go-delve/delve/issues/1359 <https://github.com/go-delve/delve/issues/1359> http://blog.gary-lai.com/missing-headers-in-mac-osx-10-14/ <http://blog.gary-lai.com/missing-headers-in-mac-osx-10-14/> https://stackoverflow.com/questions/50925160/macos-10-14beta-how-to-install-command-line-tools-macos-10-14-for-xcode-10-bet#50926354 <https://stackoverflow.com/questions/50925160/macos-10-14beta-how-to-install-command-line-tools-macos-10-14-for-xcode-10-bet#50926354>