[TypeLowering] Loosen assertion.

Author: nate-chandler

lib/SIL/IR/TypeLowering.cpp

@@ -3187,10 +3187,19 @@ void TypeConverter::verifyTrivialLowering(const TypeLowering &lowering,
   if (!lowering.isTrivial() && conformance) {
     // A non-trivial type can have a conformance in one case:
     // (1) contains a conforming archetype
+    // (2) is resilient with minimal expansion
     bool hasNoConformingArchetypeNode = visitAggregateLeaves(
         origType, substType, forExpansion,
         /*isLeaf=*/
         [&](auto ty, auto origTy, auto *field, auto index) -> bool {
+          // A resilient type that's with minimal expansion may be non-trivial
+          // but still conform (case (2)).
+          auto *nominal = ty.getAnyNominal();
+          if (nominal && nominal->isResilient() &&
+              forExpansion.getResilienceExpansion() ==
+                  ResilienceExpansion::Minimal) {
+            return true;
+          }
           // Walk into every aggregate.
           return false;
         },
@@ -3201,7 +3210,16 @@ void TypeConverter::verifyTrivialLowering(const TypeLowering &lowering,
                  "leaf of non-trivial BitwiseCopyable type that doesn't "
                  "conform to BitwiseCopyable!?");
 
-          // An archetype may conform but be non-trivial (case (2)).
+          // A resilient type that's with minimal expansion may be non-trivial
+          // but still conform (case (2)).
+          auto *nominal = ty.getAnyNominal();
+          if (nominal && nominal->isResilient() &&
+              forExpansion.getResilienceExpansion() ==
+                  ResilienceExpansion::Minimal) {
+            return false;
+          }
+
+          // An archetype may conform but be non-trivial (case (1)).
           if (origTy.isTypeParameter())
             return false;
 

test/IRGen/bitwise_copyable_resilient.swift

@@ -0,0 +1,55 @@
+// RUN: %empty-directory(%t)
+// RUN: split-file %s %t
+
+// RUN: %target-swift-frontend                           \
+// RUN:     %t/Library.swift                             \
+// RUN:     -emit-module                                 \
+// RUN:     -enable-library-evolution                    \
+// RUN:     -enable-experimental-feature BitwiseCopyable \
+// RUN:     -module-name Library                         \
+// RUN:     -emit-module-path %t/Library.swiftmodule
+
+// RUN: %target-swift-frontend                           \
+// RUN:     %t/Downstream.swift                          \
+// RUN:     -typecheck -verify                           \
+// RUN:     -debug-diagnostic-names                      \
+// RUN:     -enable-experimental-feature BitwiseCopyable \
+// RUN:     -I %t
+
+//--- Library.swift
+public enum Oopsional<T> {
+case someone(T)
+case nobody
+}
+
+@frozen public enum Woopsional<T> {
+case somebody(T)
+case noone
+}
+
+public struct Integer {
+  var value: Int
+}
+
+//--- Downstream.swift
+import Library
+
+func take<T: _BitwiseCopyable>(_ t: T) {}
+
+struct S_Explicit_With_Oopsional<T> : _BitwiseCopyable {
+  var o: Oopsional<T> // expected-error{{non_bitwise_copyable_type_member}}
+}
+
+func passOopsional<T>(_ t: Oopsional<T>) { take(t) } // expected-error   {{type_does_not_conform_decl_owner}}
+                                                     // expected-note@-7 {{where_requirement_failure_one_subst}}
+
+
+struct S_Explicit_With_Woopsional<T> : _BitwiseCopyable {
+  var o: Woopsional<T> // expected-error{{non_bitwise_copyable_type_member}}
+}
+
+func passWoopsional<T>(_ t: Woopsional<T>) { take(t) } // expected-error    {{type_does_not_conform_decl_owner}}
+                                                       // expected-note@-15 {{where_requirement_failure_one_subst}}
+
+extension Integer : @retroactive _BitwiseCopyable {} // expected-error {{bitwise_copyable_outside_module}}
+

test/Sema/bitwise_copyable_2.swift

@@ -25,3 +25,13 @@ indirect enum E_Explicit_Indirect : _BitwiseCopyable { // expected-error {{non_b
 enum E_Explicit_Indirect_Case : _BitwiseCopyable { // expected-error {{non_bitwise_copyable_type_indirect_enum_element}}
   indirect case s(S) // expected-note {{note_non_bitwise_copyable_type_indirect_enum_element}}
 }
+
+func take<T : _BitwiseCopyable>(_ t: T) {}
+
+// public (effectively) => !conforms
+@usableFromInline internal struct InternalUsableStruct {
+  public var int: Int
+}
+
+func passInternalUsableStruct(_ s: InternalUsableStruct) { take(s) } // expected-error{{type_does_not_conform_decl_owner}}
+                                                                     // expected-note@-8{{where_requirement_failure_one_subst}}

test/Sema/bitwise_copyable_package_resilience.swift

@@ -0,0 +1,42 @@
+// RUN: %empty-directory(%t)
+// RUN: split-file %s %t
+
+// RUN: %target-swift-frontend                           \
+// RUN:     %t/Library.swift                             \
+// RUN:     -emit-module                                 \
+// RUN:     -package-name Package                        \
+// RUN:     -enable-library-evolution                    \
+// RUN:     -enable-experimental-feature BitwiseCopyable \
+// RUN:     -module-name Library                         \
+// RUN:     -emit-module-path %t/Library.swiftmodule     \
+// RUN:     -emit-module-interface-path %t/Library.swiftinterface
+
+// RUN: %target-swift-frontend                           \
+// RUN:     %t/Downstream.swift                          \
+// RUN:     -typecheck -verify                           \
+// RUN:     -package-name Package                        \
+// RUN:     -debug-diagnostic-names                      \
+// RUN:     -enable-experimental-feature BitwiseCopyable \
+// RUN:     -I %t
+
+//--- Library.swift
+
+// !public => conforms
+package struct PackageStruct {
+  package var int: Int
+}
+
+// Public => !conforms
+public struct PublicStruct {
+  public var int: Int
+}
+
+//--- Downstream.swift
+import Library
+
+func take<T : _BitwiseCopyable>(_ t: T) {}
+
+func passPackageStruct(_ s: PackageStruct) { take(s) }
+
+func passPublicStruct(_ s: PublicStruct) { take(s) } // expected-error{{type_does_not_conform_decl_owner}}
+                                                     // expected-note@-5{{where_requirement_failure_one_subst}}