+void GC_allow_register_threads (void)
+{
+ /* No-op for GC pre-v7. */
+}
+
+int GC_register_my_thread (struct GC_stack_base *sb)
+{
+# if defined(GC_DLL) || defined(GC_INSIDE_DLL)
+ /* Registered by DllMain. */
+ return GC_DUPLICATE;
+# else
+ /* TODO: Implement. */
+ return GC_UNIMPLEMENTED;
+# endif
+}
+