Merge pull request #80197 from swiftlang/gaborh/mutating-class-func

[cxx-interop] Do not create mutating properties for classes

Author: Xazax-hun

lib/ClangImporter/SwiftDeclSynthesizer.cpp

@@ -129,7 +129,8 @@ static AccessorDecl *makeFieldSetterDecl(ClangImporter::Implementation &Impl,
       params, voidTy, importedDecl, clangNode);
   setterDecl->setIsObjC(false);
   setterDecl->setIsDynamic(false);
-  setterDecl->setSelfAccessKind(SelfAccessKind::Mutating);
+  if (!isa<ClassDecl>(importedDecl))
+    setterDecl->setSelfAccessKind(SelfAccessKind::Mutating);
   setterDecl->setAccess(importedFieldDecl->getFormalAccess());
 
   return setterDecl;

test/Interop/Cxx/class/inline-function-codegen/Inputs/method-calls-function.h

@@ -9,4 +9,18 @@ struct Incrementor {
 
 inline int callMethod(int value) { return Incrementor().callIncrement(value); }
 
+class __attribute__((swift_attr("import_reference")))
+__attribute__((swift_attr("retain:immortal")))
+__attribute__((swift_attr("release:immortal")))
+__attribute__((swift_attr("unsafe"))) Cell {
+public:
+  bool is_marked() const { return m_marked; }
+  void set_marked(bool b) { m_marked = b; }
+
+private:
+  bool m_marked : 1 {false};
+};
+
+inline Cell *_Nonnull createCell() { return new Cell{}; }
+
 #endif // TEST_INTEROP_CXX_CLASS_INLINE_FUNCTION_THROUGH_MEMBER_INPUTS_METHOD_CALLS_FUNCTION_H

test/Interop/Cxx/class/inline-function-codegen/method-calls-function-execution.swift

@@ -1,4 +1,4 @@
-// RUN: %target-run-simple-swift(-I %S/Inputs -Xfrontend -enable-experimental-cxx-interop)
+// RUN: %target-run-simple-swift(-I %S/Inputs -Xfrontend -cxx-interoperability-mode=default -Xcc -std=c++20 -Xfrontend -disable-availability-checking)
 //
 // REQUIRES: executable_test
 
@@ -11,4 +11,11 @@ MembersTestSuite.test("method calls function") {
   expectEqual(42, callMethod(41))
 }
 
+func doSomethingWith(_ s: Cell) { s.set_marked(true) }
+
+MembersTestSuite.test("method sets bitfield") {
+  let s = createCell()
+  doSomethingWith(s)
+}
+
 runAllTests()