Merge pull request #76653 from swiftlang/gaborh/unsafe_reference

[cxx-interop] Import SWIFT_UNSAFE_REFERENCE types as @unsafe

Author: Xazax-hun

lib/ClangImporter/SwiftBridging/swift/bridging

@@ -103,7 +103,8 @@
 #define SWIFT_UNSAFE_REFERENCE                                                  \
   __attribute__((swift_attr("import_reference")))                         \
   __attribute__((swift_attr(_CXX_INTEROP_STRINGIFY(retain:immortal))))    \
-  __attribute__((swift_attr(_CXX_INTEROP_STRINGIFY(release:immortal))))
+  __attribute__((swift_attr(_CXX_INTEROP_STRINGIFY(release:immortal))))   \
+  __attribute__((swift_attr("unsafe")))
 
 /// Specifies a name that will be used in Swift for this declaration instead of its original name.
 #define SWIFT_NAME(_name) __attribute__((swift_name(#_name)))

test/Interop/Cxx/class/safe-interop-mode.swift

@@ -28,6 +28,8 @@ struct SWIFT_ESCAPABLE Owner {};
 
 struct Unannotated {};
 
+struct SWIFT_UNSAFE_REFERENCE UnsafeReference {};
+
 //--- test.swift
 
 import Test
@@ -36,6 +38,10 @@ import CoreFoundation
 func useUnsafeParam(x: Unannotated) { // expected-warning{{reference to unsafe struct 'Unannotated'}}
 }
 
+@available(macOS 13.4, *)
+func useUnsafeParam2(x: UnsafeReference) { // expected-warning{{reference to unsafe class 'UnsafeReference'}}
+}
+
 func useSafeParams(x: Owner, y: View) {
 }