[interop] do not synthesize special members for C++ records with incomplete fields

The incomplete fields will trigger different assertions when clang is sythensizing constructors/destructors

rdar://109417079

Author: hyp

lib/ClangImporter/ImportDecl.cpp

@@ -841,6 +841,26 @@ ImportedType findOptionSetType(clang::QualType type,
   return importedType;
 }
 
+static bool areRecordFieldsComplete(const clang::CXXRecordDecl *decl) {
+  for (const auto *f : decl->fields()) {
+    auto *fieldRecord = f->getType()->getAsCXXRecordDecl();
+    if (fieldRecord) {
+      if (!fieldRecord->isCompleteDefinition()) {
+        return false;
+      }
+      if (!areRecordFieldsComplete(fieldRecord))
+        return false;
+    }
+  }
+  for (const auto base : decl->bases()) {
+    if (auto *baseRecord = base.getType()->getAsCXXRecordDecl()) {
+      if (!areRecordFieldsComplete(baseRecord))
+        return false;
+    }
+  }
+  return true;
+}
+
 namespace {
   /// Customized llvm::DenseMapInfo for storing borrowed APSInts.
   struct APSIntRefDenseMapInfo {
@@ -2663,10 +2683,11 @@ namespace {
       auto &clangSema = Impl.getClangSema();
       // Make Clang define any implicit constructors it may need (copy,
       // default). Make sure we only do this if the class has been fully defined
-      // and we're not in a dependent context (this is equivalent to the logic
-      // in CanDeclareSpecialMemberFunction in Clang's SemaLookup.cpp).
-      // TODO: I suspect this if-statement does not need to be here.
-      if (!decl->isBeingDefined() && !decl->isDependentContext()) {
+      // with complete fields, and we're not in a dependent context(this is
+      // equivalent to the logic in CanDeclareSpecialMemberFunction in Clang's
+      // SemaLookup.cpp).
+      if (!decl->isBeingDefined() && !decl->isDependentContext() &&
+          areRecordFieldsComplete(decl)) {
         if (decl->needsImplicitDefaultConstructor()) {
           clang::CXXConstructorDecl *ctor =
               clangSema.DeclareImplicitDefaultConstructor(

test/Interop/Cxx/foreign-reference/nullable-module-interface.swift

@@ -9,9 +9,9 @@
 // CHECK: func mutateIt(_: Empty)
 
 // CHECK: class IntPair {
-// CHECK:   var a: Int32
-// CHECK:   var b: Int32
 // CHECK:   func test() -> Int32
 // CHECK:   class func create() -> IntPair!
+// CHECK:   var a: Int32
+// CHECK:   var b: Int32
 // CHECK: }
 // CHECK: func mutateIt(_ x: IntPair!)

test/Interop/Cxx/foreign-reference/pod-module-interface.swift

@@ -20,60 +20,60 @@
 
 // CHECK: class IntPair {
 // CHECK-NOT: init
-// CHECK:   var a: Int32
-// CHECK:   var b: Int32
 // CHECK:   func test() -> Int32
 // CHECK:   func testMutable() -> Int32
 // CHECK:   class func create() -> IntPair
+// CHECK:   var a: Int32
+// CHECK:   var b: Int32
 // CHECK: }
 // CHECK: func mutateIt(_ x: IntPair)
 // CHECK-NOT: func passThroughByValue(_ x: IntPair) -> IntPair
 
 // CHECK: class RefHoldingPair {
 // CHECK-NOT: init
 // CHECK-NOT: pair
-// CHECK:   var otherValue: Int32
 // CHECK:   func test() -> Int32
 // CHECK:   func testMutable() -> Int32
 // CHECK:   class func create() -> RefHoldingPair
+// CHECK:   var otherValue: Int32
 // CHECK: }
 
 // CHECK: class RefHoldingPairRef {
 // CHECK-NOT: init
-// CHECK:   var pair: IntPair
-// CHECK:   var otherValue: Int32
 // CHECK:   func test() -> Int32
 // CHECK:   func testMutable() -> Int32
 // CHECK:   class func create() -> RefHoldingPairRef
+// CHECK:   var pair: IntPair
+// CHECK:   var otherValue: Int32
 // CHECK: }
 
 // CHECK: class RefHoldingPairPtr {
 // CHECK-NOT: init
-// CHECK:   var pair: IntPair
-// CHECK:   var otherValue: Int32
 // CHECK:   func test() -> Int32
 // CHECK:   func testMutable() -> Int32
 // CHECK:   class func create() -> RefHoldingPairPtr
+// CHECK:   var pair: IntPair
+// CHECK:   var otherValue: Int32
 // CHECK: }
 
 // CHECK: struct ValueHoldingPair {
 // CHECK-NOT: init
 // CHECK-NOT: pair
 // CHECK:   init()
-// CHECK:   var otherValue: Int32
 // CHECK:   func test() -> Int32
 // CHECK:   mutating func testMutable() -> Int32
 // CHECK:   static func create() -> UnsafeMutablePointer<ValueHoldingPair>
+// CHECK:   var otherValue: Int32
 // CHECK: }
 
 // CHECK: class BigType {
 // CHECK-NOT: init
-// CHECK:   var a: Int32
-// CHECK:   var b: Int32
-// CHECK:   var buffer:
 // CHECK:   func test() -> Int32
 // CHECK:   func testMutable() -> Int32
 // CHECK:   class func create() -> BigType
+// CHECK:   var a: Int32
+// CHECK:   var b: Int32
+// CHECK:   var buffer:
 // CHECK: }
 // CHECK: func mutateIt(_ x: BigType)
 // CHECK-NOT: func passThroughByValue(_ x: BigType) -> BigType

test/Interop/Cxx/foreign-reference/singleton-module-interface.swift

@@ -4,36 +4,36 @@
 
 // CHECK: class DeletedDtor {
 // CHECK-NOT: init
-// CHECK:   var value: Int32
 // CHECK:   func test() -> Int32
 // CHECK:   func testMutable() -> Int32
 // CHECK:   class func create() -> DeletedDtor
+// CHECK:   var value: Int32
 // CHECK: }
 // CHECK: func mutateIt(_ x: DeletedDtor)
 
 // CHECK: class PrivateDtor {
 // CHECK-NOT: init
-// CHECK:   var value: Int32
 // CHECK:   func test() -> Int32
 // CHECK:   func testMutable() -> Int32
 // CHECK:   class func create() -> PrivateDtor
+// CHECK:   var value: Int32
 // CHECK: }
 // CHECK: func mutateIt(_ x: PrivateDtor)
 
 // CHECK: class DeletedSpecialMembers {
 // CHECK-NOT: init
-// CHECK:   var value: Int32
 // CHECK:   func test() -> Int32
 // CHECK:   func testMutable() -> Int32
 // CHECK:   class func create() -> DeletedSpecialMembers
+// CHECK:   var value: Int32
 // CHECK: }
 // CHECK: func mutateIt(_ x: DeletedSpecialMembers)
 
 // CHECK: class PrivateSpecialMembers {
 // CHECK-NOT: init
-// CHECK:   var value: Int32
 // CHECK:   func test() -> Int32
 // CHECK:   func testMutable() -> Int32
 // CHECK:   class func create() -> PrivateSpecialMembers
+// CHECK:   var value: Int32
 // CHECK: }
 // CHECK: func mutateIt(_ x: PrivateSpecialMembers)