swift

5bf2c937 - [CMake] [Darwin] Don't build the SDK overlays by default on Apple platforms

[CMake] [Darwin] Don't build the SDK overlays by default on Apple platforms The Apple SDKs have been providing the Darwin overlay since macOS 10.14.4, iOS 12.2, et al. More recently the SDK version has diverged from the Swift version making them incompatible. Stop building the overlay from Swift. Once the SDK overlays aren't being built, the clang overlays need to be built in testing. rdar://115192929