diff --git a/core/include/thread.h b/core/include/thread.h
index 64a828ab31..3a13e379c8 100644
--- a/core/include/thread.h
+++ b/core/include/thread.h
@@ -209,6 +209,9 @@ struct _thread {
     const char *name;               /**< thread's name                  */
     int stack_size;                 /**< thread's stack size            */
 #endif
+#ifdef HAVE_THREAD_ARCH_T
+    thread_arch_t arch;             /**< architecture dependent part    */
+#endif
 };
 
 /**