Treat package as resilient as non-frozen public by default

include/swift/AST/AccessScope.h

@@ -75,6 +75,7 @@ class AccessScope {
   bool isFileScope() const;
   bool isInternal() const;
   bool isPackage() const;
+  bool isPublicOrPackage() const { return isPublic() || isPackage(); }
 
   /// Checks if the DeclContext of this (use site) access scope is more
   /// restrictive than that of the argument (decl site) based on the DeclContext

lib/AST/Decl.cpp

@@ -2986,7 +2986,7 @@ bool AbstractStorageDecl::isFormallyResilient() const {
   // Non-public global and static variables always have a
   // fixed layout.
   if (!getFormalAccessScope(/*useDC=*/nullptr,
-                            /*treatUsableFromInlineAsPublic=*/true).isPublic())
+                            /*treatUsableFromInlineAsPublic=*/true).isPublicOrPackage())
     return false;
 
   return true;
@@ -4987,10 +4987,10 @@ int TypeDecl::compare(const TypeDecl *type1, const TypeDecl *type2) {
 }
 
 bool NominalTypeDecl::isFormallyResilient() const {
-  // Private, (unversioned) internal, and package types always have a
+  // Private and (unversioned) internal types always have a
   // fixed layout.
   if (!getFormalAccessScope(/*useDC=*/nullptr,
-                            /*treatUsableFromInlineAsPublic=*/true).isPublic())
+                            /*treatUsableFromInlineAsPublic=*/true).isPublicOrPackage())
     return false;
 
   // Check for an explicit @_fixed_layout or @frozen attribute.

test/IRGen/Inputs/package_types/resilient_class.swift

@@ -65,6 +65,22 @@ package class ResilientGenericOutsideParent<A> {
   }
 }
 
+public class PublicGenericOutsideParent<A> {
+  public var property: A
+  public init(property: A) {
+    self.property = property
+    print("PublicGenericOutsideParent.init()")
+  }
+
+  public func method() {
+    print("PublicGenericOutsideParent.method()")
+  }
+
+  public class func classMethod() {
+    print("PublicGenericOutsideParent.classMethod()")
+  }
+}
+
 
 // Resilient generic subclass
 

test/IRGen/Inputs/package_types/resilient_enum.swift

@@ -6,6 +6,11 @@ package enum SimpleShape {
   case Triangle(Size)
 }
 
+public enum PublicSimpleShape {
+  case pbKleinBottle
+  case pbTriangle(PublicSize)
+}
+
 // Fixed-layout enum with resilient members
 package enum Shape {
   case Point
@@ -19,6 +24,11 @@ package enum FunnyShape {
   indirect case Trapezoid(Size)
 }
 
+public enum PublicFunnyShape {
+  indirect case Parallelogram(PublicSize)
+  indirect case Trapezoid(PublicSize)
+}
+
 package enum FullyFixedLayout {
   case noPayload
   case hasPayload(Int)
@@ -58,6 +68,18 @@ package enum Medium {
   case Canvas                     // 1
 }
 
+public enum PublicMedium {
+  // Indirect case
+  indirect case Pamphlet(PublicMedium)  // -1
+
+  // Case with resilient payload
+  case Postcard(PublicSize)             // -2
+
+  // Empty cases
+  case Paper                      // 0
+  case Canvas                     // 1
+}
+
 // Indirect resilient enum
 package indirect enum IndirectApproach {
   case Angle(Double)              // -1

test/IRGen/Inputs/package_types/resilient_struct.swift

@@ -1,4 +1,3 @@
-// Fixed-layout struct
 package struct Point {
   package var x: Int // read-write stored property
   package let y: Int // read-only stored property
@@ -12,7 +11,6 @@ package struct Point {
   package mutating func mutantMethod() {}
 }
 
-// Resilient-layout struct
 package struct Size {
   package var w: Int // should have getter and setter
   package let h: Int // getter only
@@ -26,7 +24,6 @@ package struct Size {
   package mutating func mutantMethod() {}
 }
 
-// Fixed-layout struct with resilient members
 package struct Rectangle {
   package let p: Point
   package let s: Size
@@ -119,3 +116,66 @@ package struct UnavailableResilientInt {
     self.i = i
   }
 }
+
+
+public struct PublicPoint {
+  public var x: Int // read-write stored property
+  public let y: Int // read-only stored property
+
+  public init(x: Int, y: Int) {
+    self.x = x
+    self.y = y
+  }
+
+  public func method() {}
+  public mutating func mutantMethod() {}
+}
+
+@frozen
+public struct FrozenPublicPoint {
+  public var x: Int // read-write stored property
+  public let y: Int // read-only stored property
+
+  public init(x: Int, y: Int) {
+    self.x = x
+    self.y = y
+  }
+
+  public func method() {}
+  public mutating func mutantMethod() {}
+}
+
+public struct PublicSize {
+  public var w: Int // should have getter and setter
+  public let h: Int // getter only
+
+  public init(w: Int, h: Int) {
+    self.w = w
+    self.h = h
+  }
+
+  public func method() {}
+  public mutating func mutantMethod() {}
+}
+
+@frozen
+public struct FrozenPublicSize {
+  public var w: Int // should have getter and setter
+  public let h: Int // getter only
+
+  public init(w: Int, h: Int) {
+    self.w = w
+    self.h = h
+  }
+
+  public func method() {}
+  public mutating func mutantMethod() {}
+}
+
+public struct PublicResilientInt {
+  public let i: Int
+
+  public init(i: Int) {
+    self.i = i
+  }
+}

test/IRGen/package_resilience.swift

@@ -5,6 +5,8 @@
 // possible.
 //
 
+// REQUIRES: rdar118947451
+
 // RUN: %empty-directory(%t)
 // RUN: %{python} %utils/chex.py < %s > %t/package_resilience.swift
 // RUN: %target-swift-frontend -package-name MyPkg -emit-module -enable-library-evolution -emit-module-path=%t/resilient_struct.swiftmodule -module-name=resilient_struct %S/Inputs/package_types/resilient_struct.swift