This is failing while building foundation, nothing related to the changes listed.
/home/buildnode/jenkins/workspace/oss-swift-package-linux-ubuntu-16_04/swift-corelibs-libdispatch/src/swift/Block.swift:14:8: error: no such module '_SwiftDispatchOverlayShims'
**06:04:21** import _SwiftDispatchOverlayShims
**06:04:21** ^