stdlib: Add some @_versioned declarations to fix resilient build

A recent change made accessibility checking stricter. This had some
fallout on the half-baked @_versioned attribute, where we could no
longer define @_versioned members on a non-@_versioned type.

This was wrong anyway (and will be diagnosed when we add proper
diagnostics for @_versioned), because type metadata for the
internal type did not get the right linkage, but it used to work
as long as you didn't try to get the type metadata at runtime.

This patch adds @_versioned attributes to the right types now that
this broken behavior is gone.

As a result, _Variant{Set,Dictionary}Storage became resilient
(non-@_versioned internal types are not resilient), which broke
too many tests that assumed you can exhaustively switch over all
the cases. Since eager-bridging is going to eliminate this enum
anyway (or so I've heard), make it @_fixed_layout for now.

Author: slavapestov

stdlib/public/core/ArrayBuffer.swift

@@ -21,6 +21,7 @@ import SwiftShims
 internal typealias _ArrayBridgeStorage
   = _BridgeStorage<_ContiguousArrayStorageBase, _NSArrayCore>
 
+@_versioned
 @_fixed_layout
 internal struct _ArrayBuffer<Element> : _ArrayBufferProtocol {
 
@@ -29,6 +30,7 @@ internal struct _ArrayBuffer<Element> : _ArrayBufferProtocol {
     _storage = _ArrayBridgeStorage(native: _emptyArrayStorage)
   }
 
+  @_versioned  // FIXME(abi): Used from tests
   internal init(nsArray: _NSArrayCore) {
     _sanityCheck(_isClassOrObjCExistential(Element.self))
     _storage = _ArrayBridgeStorage(objC: nsArray)
@@ -113,6 +115,7 @@ extension _ArrayBuffer {
   /// Convert to an NSArray.
   ///
   /// O(1) if the element type is bridged verbatim, O(*n*) otherwise.
+  @_versioned  // FIXME(abi): Used from tests
   internal func _asCocoaArray() -> _NSArrayCore {
     return _fastPath(_isNative) ? _native._asCocoaArray() : _nonNative
   }
@@ -273,6 +276,7 @@ extension _ArrayBuffer {
   /// A pointer to the first element.
   ///
   /// - Precondition: The elements are known to be stored contiguously.
+  @_versioned
   internal var firstElementAddress: UnsafeMutablePointer<Element> {
     _sanityCheck(_isNative, "must be a native buffer")
     return _native.firstElementAddress

stdlib/public/core/ArrayBufferProtocol.swift

@@ -12,6 +12,7 @@
 
 /// The underlying buffer for an ArrayType conforms to
 /// `_ArrayBufferProtocol`.  This buffer does not provide value semantics.
+@_versioned
 internal protocol _ArrayBufferProtocol
   : MutableCollection, RandomAccessCollection {
 

stdlib/public/core/Builtin.swift

@@ -283,6 +283,7 @@ public func _onFastPath() {
 // Declare it here instead of RuntimeShims.h, because we need to specify
 // the type of argument to be AnyClass. This is currently not possible
 // when using RuntimeShims.h
+@_versioned
 @_silgen_name("swift_objc_class_usesNativeSwiftReferenceCounting")
 func _usesNativeSwiftReferenceCounting(_ theClass: AnyClass) -> Bool
 #else
@@ -480,6 +481,7 @@ internal func _makeBridgeObject(
   )
 }
 
+@_versioned
 @_silgen_name("_swift_class_getSuperclass")
 internal func _swift_class_getSuperclass(_ t: AnyClass) -> AnyClass?
 

stdlib/public/core/ContiguousArrayBuffer.swift

@@ -176,6 +176,7 @@ final class _ContiguousArrayStorage<Element> : _ContiguousArrayStorage1 {
   }
 }
 
+@_versioned
 @_fixed_layout
 internal struct _ContiguousArrayBuffer<Element> : _ArrayBufferProtocol {
 
@@ -247,6 +248,7 @@ internal struct _ContiguousArrayBuffer<Element> : _ArrayBufferProtocol {
   }
 
   /// A pointer to the first element.
+  @_versioned
   internal var firstElementAddress: UnsafeMutablePointer<Element> {
     return UnsafeMutablePointer(Builtin.projectTailElems(_storage,
                                                          Element.self))
@@ -318,6 +320,7 @@ internal struct _ContiguousArrayBuffer<Element> : _ArrayBufferProtocol {
   }
 
   /// Get or set the value of the ith element.
+  @_versioned
   internal subscript(i: Int) -> Element {
     get {
       return getElement(i)
@@ -434,6 +437,7 @@ internal struct _ContiguousArrayBuffer<Element> : _ArrayBufferProtocol {
 #endif
 
   /// An object that keeps the elements stored in this buffer alive.
+  @_versioned
   internal var owner: AnyObject {
     return _storage
   }

stdlib/public/core/HashedCollections.swift.gyb

@@ -2508,6 +2508,7 @@ internal struct _HashedContainerStorageHeader {
 /// Enough bytes are allocated to hold the bitmap for marking valid entries,
 /// keys, and values. The data layout starts with the bitmap, followed by the
 /// keys, followed by the values.
+@_versioned
 final internal class _Native${Self}StorageImpl<${TypeParameters}> {
   // Note: It is intended that ${TypeParameters}
   // (without : Hashable) is used here - this storage must work
@@ -3229,6 +3230,7 @@ final internal class _Native${Self}StorageKeyNSEnumerator<
 /// is also a proper `NS${Self}` subclass, which is returned to Objective-C
 /// during bridging.  `${Self}Index` points directly to
 /// `_Native${Self}Storage`.
+@_versioned
 final internal class _Native${Self}StorageOwner<${TypeParametersDecl}>
   : _SwiftNativeNS${Self}, _NS${Self}Core {
 
@@ -3564,7 +3566,10 @@ final internal class _Native${Self}StorageOwner<${TypeParametersDecl}>
 }
 
 #if _runtime(_ObjC)
+@_versioned
+@_fixed_layout
 internal struct _Cocoa${Self}Storage : _HashStorage {
+  @_versioned
   internal var cocoa${Self}: _NS${Self}
 
   internal typealias Index = _Cocoa${Self}Index
@@ -3695,6 +3700,8 @@ internal struct _Cocoa${Self}Storage : _HashStorage {
 internal struct _Cocoa${Self}Storage {}
 #endif
 
+@_versioned
+@_fixed_layout
 internal enum _Variant${Self}Storage<${TypeParametersDecl}> : _HashStorage {
 
   internal typealias NativeStorage = _Native${Self}Storage<${TypeParameters}>
@@ -4408,6 +4415,7 @@ internal enum _Variant${Self}Storage<${TypeParametersDecl}> : _HashStorage {
   }
 }
 
+@_versioned
 internal struct _Native${Self}Index<${TypeParametersDecl}> :
   Comparable {
 
@@ -4418,6 +4426,8 @@ internal struct _Native${Self}Index<${TypeParametersDecl}> :
   // the new model.
   @_versioned
   internal var nativeStorage: NativeStorage
+
+  @_versioned
   internal var offset: Int
 
   @_versioned
@@ -4799,6 +4809,7 @@ final internal class _Cocoa${Self}Iterator : IteratorProtocol {
 final internal class _Cocoa${Self}Iterator {}
 #endif
 
+@_versioned
 internal enum ${Self}IteratorRepresentation<${TypeParametersDecl}> {
   internal typealias _Iterator = ${Self}Iterator<${TypeParameters}>
   internal typealias _NativeStorageOwner =

stdlib/public/core/SipHash.swift.gyb

@@ -19,12 +19,15 @@
 /// * Daniel J. Bernstein <[email protected]>
 //===----------------------------------------------------------------------===//
 
+@_versioned
 internal enum _SipHashDetail {
+  @_versioned
   @inline(__always)
   internal static func _rotate(_ x: UInt64, leftBy amount: Int) -> UInt64 {
     return (x << UInt64(amount)) | (x >> (64 - UInt64(amount)))
   }
 
+  @_versioned
   @inline(__always)
   internal static func _loadUnalignedUInt64LE(
     from p: UnsafeRawPointer
@@ -40,6 +43,7 @@ internal enum _SipHashDetail {
       (UInt64(p.load(fromByteOffset: 7, as: UInt8.self)) << 56)
   }
 
+  @_versioned
   @inline(__always)
   internal static func _loadPartialUnalignedUInt64LE(
     from p: UnsafeRawPointer,
@@ -57,6 +61,7 @@ internal enum _SipHashDetail {
     return result
   }
 
+  @_versioned
   @inline(__always)
   internal static func _sipRound(
     v0: inout UInt64,
@@ -87,16 +92,28 @@ internal enum _SipHashDetail {
 public // @testable
 struct ${Self} {
   // "somepseudorandomlygeneratedbytes"
+  @_versioned
   internal var v0: UInt64 = 0x736f6d6570736575
+
+  @_versioned
   internal var v1: UInt64 = 0x646f72616e646f6d
+
+  @_versioned
   internal var v2: UInt64 = 0x6c7967656e657261
+
+  @_versioned
   internal var v3: UInt64 = 0x7465646279746573
 
+  @_versioned
   internal var hashedByteCount: UInt64 = 0
 
+  @_versioned
   internal var dataTail: UInt64 = 0
+
+  @_versioned
   internal var dataTailByteCount: Int = 0
 
+  @_versioned
   internal var finalizedHash: UInt64?
 
   public init(key: (UInt64, UInt64)) {
@@ -113,6 +130,7 @@ struct ${Self} {
   }
 
   // FIXME(ABI)#63 (UnsafeRawBufferPointer): Use UnsafeRawBufferPointer.
+  @_versioned
   @inline(__always)
   internal mutating func _append_alwaysInline(
     _ data: UnsafeRawPointer,
@@ -165,6 +183,7 @@ struct ${Self} {
 
   /// This function mixes in the given word directly into the state,
   /// ignoring `dataTail`.
+  @_versioned
   @inline(__always)
   internal mutating func _appendDirectly(_ m: UInt64) {
     v3 ^= m
@@ -188,6 +207,7 @@ struct ${Self} {
     return _finalizeAndReturnHash_alwaysInline()
   }
 
+  @_versioned
   @inline(__always)
   internal mutating func _finalizeAndReturnHash_alwaysInline() -> UInt64 {
     if let finalizedHash = finalizedHash {
@@ -238,6 +258,7 @@ struct ${Self} {
   }
 
   // FIXME(ABI)#65 (UnsafeRawBufferPointer): Use UnsafeRawBufferPointer.
+  @_versioned
   @inline(__always)
   public // @testable
   static func _hash_alwaysInline(

stdlib/public/core/SliceBuffer.swift

@@ -11,6 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 /// Buffer type for `ArraySlice<Element>`.
+@_versioned
 internal struct _SliceBuffer<Element>
   : _ArrayBufferProtocol,
     RandomAccessCollection
@@ -121,6 +122,7 @@ internal struct _SliceBuffer<Element>
   internal var owner: AnyObject
   internal let subscriptBaseAddress: UnsafeMutablePointer<Element>
 
+  @_versioned
   internal var firstElementAddress: UnsafeMutablePointer<Element> {
     return subscriptBaseAddress + startIndex
   }