         ) rethrows -> R
 }
 
-@available(iOS 13.0, macOS 10.14, tvOS 13.0, watchOS 6.0, *)
+@available(iOS 9999, OSX 9999, tvOS 9999, watchOS 9999, *)
 public extension _ContiguousCollection {
     func withUnsafeBufferPointer<R>(
         _ body: (UnsafeBufferPointer<Element>) throws -> R

//===----------------------------------------------------------------------===//

/// A collection that supports access to its underlying contiguous storage.
@available(iOS 13.0, macOS 10.14, tvOS 13.0, watchOS 6.0, *)
public protocol _ContiguousCollection: Collection
where SubSequence: _ContiguousCollection {
    /// Calls a closure with a pointer to the array's contiguous storage.

    }
}

@available(iOS 9999, OSX 9999, tvOS 9999, watchOS 9999, *)
extension Array: _MutableContiguousCollection { }

@available(iOS 9999, OSX 9999, tvOS 9999, watchOS 9999, *)
extension ContiguousArray: _MutableContiguousCollection { }

@available(iOS 9999, OSX 9999, tvOS 9999, watchOS 9999, *)
extension ArraySlice: _MutableContiguousCollection { }

@available(iOS 9999, OSX 9999, tvOS 9999, watchOS 9999, *)
extension UnsafeBufferPointer: _ContiguousCollection { }

@available(iOS 9999, OSX 9999, tvOS 9999, watchOS 9999, *)
extension UnsafeMutableBufferPointer: _MutableContiguousCollection { }

@available(iOS 9999, OSX 9999, tvOS 9999, watchOS 9999, *)
extension Slice: _ContiguousCollection where Base: _ContiguousCollection { }

@available(iOS 9999, OSX 9999, tvOS 9999, watchOS 9999, *)
extension Slice: _MutableContiguousCollection where Base: _MutableContiguousCollection { }
