Merge pull request #60778 from zoecarver/dont-import-reference-type-ctors

[cxx-interop] Don't import constructors of foreign reference types.

Author: zoecarver

lib/ClangImporter/ClangImporter.cpp

@@ -4943,6 +4943,10 @@ TinyPtrVector<ValueDecl *> ClangRecordMemberLookup::evaluate(
     auto named = found.get<clang::NamedDecl *>();
     if (dyn_cast<clang::Decl>(named->getDeclContext()) ==
         recordDecl->getClangDecl()) {
+      // Don't import constructors on foreign reference types.
+      if (isa<clang::CXXConstructorDecl>(named) && isa<ClassDecl>(recordDecl))
+        continue;
+
       if (auto import = clangModuleLoader->importDeclDirectly(named))
         result.push_back(cast<ValueDecl>(import));
     }

test/Interop/Cxx/foreign-reference/no-ctor-errors.swift

@@ -0,0 +1,25 @@
+// RUN: rm -rf %t
+// RUN: split-file %s %t
+// RUN: not %target-swift-frontend -typecheck -I %t/Inputs  %t/test.swift  -enable-experimental-cxx-interop 2>&1 | %FileCheck %s
+
+//--- Inputs/module.modulemap
+module Test {
+    header "test.h"
+    requires cplusplus
+}
+
+//--- Inputs/test.h
+struct
+    __attribute__((swift_attr("import_reference")))
+    __attribute__((swift_attr("retain:immortal")))
+    __attribute__((swift_attr("release:immortal")))
+HasCtor {
+  HasCtor(int a) {}
+};
+
+//--- test.swift
+
+import Test
+
+// CHECK: error: 'HasCtor' cannot be constructed because it has no accessible initializers
+let x = HasCtor(42)