[Stdlib] Move SwiftNativeNSObject to libswiftCore.

This type can be put to good use outside of the concurrency runtime. Reexport it from libswift_Concurrency so it can still be found there as well.

rdar://79352061

Author: mikeash

stdlib/public/CMakeLists.txt

@@ -4,6 +4,7 @@ set(SWIFT_RUNTIME_CXX_FLAGS)
 set(SWIFT_RUNTIME_LINK_FLAGS)
 set(SWIFT_RUNTIME_SWIFT_COMPILE_FLAGS)
 set(SWIFT_RUNTIME_SWIFT_LINK_FLAGS)
+set(SWIFT_RUNTIME_CONCURRENCY_SWIFT_LINK_FLAGS)
 
 if(SWIFT_RUNTIME_USE_SANITIZERS)
   # TODO: Refactor this
@@ -121,3 +122,9 @@ if(SWIFT_BUILD_SDK_OVERLAY)
   endif()
 endif()
 
+if(CMAKE_SYSTEM_NAME STREQUAL "Darwin")
+  list(APPEND SWIFT_RUNTIME_CONCURRENCY_SWIFT_LINK_FLAGS
+    "-Wl,-reexported_symbols_list,${CMAKE_CURRENT_SOURCE_DIR}/Concurrency/ReexportedSymbols")
+endif()
+
+list(APPEND SWIFT_RUNTIME_CONCURRENCY_SWIFT_LINK_FLAGS "${SWIFT_RUNTIME_SWIFT_LINK_FLAGS}")

stdlib/public/Concurrency/CMakeLists.txt

@@ -10,9 +10,6 @@
 #
 #===----------------------------------------------------------------------===#
 
-set(swift_concurrency_objc_sources
-  SwiftNativeNSObject.mm)
-
 set(LLVM_OPTIONAL_SOURCES
   ${swift_concurrency_objc_sources})
 
@@ -97,6 +94,6 @@ add_swift_target_library(swift_Concurrency ${SWIFT_STDLIB_LIBRARY_BUILD_TYPES} I
     -Xfrontend -enable-experimental-concurrency
     -Xfrontend -define-availability
     -Xfrontend \"SwiftStdlib 5.5:macOS 12.0, iOS 15.0, watchOS 8.0, tvOS 15.0\"
-  LINK_FLAGS "${SWIFT_RUNTIME_SWIFT_LINK_FLAGS}"
+  LINK_FLAGS "${SWIFT_RUNTIME_CONCURRENCY_SWIFT_LINK_FLAGS}"
   INSTALL_IN_COMPONENT stdlib
 )

stdlib/public/Concurrency/ReexportedSymbols

@@ -0,0 +1,2 @@
+_OBJC_CLASS_$_SwiftNativeNSObject
+_OBJC_METACLASS_$_SwiftNativeNSObject

stdlib/public/stubs/CMakeLists.txt

@@ -13,6 +13,7 @@ set(swift_stubs_objc_sources
     FoundationHelpers.mm
     OptionalBridgingHelper.mm
     Reflection.mm
+    SwiftNativeNSObject.mm
     SwiftNativeNSXXXBaseARC.m)
 set(swift_stubs_gyb_sources
     SwiftNativeNSXXXBase.mm.gyb)