diff --git a/sys/sys/linker_set.h b/sys/sys/linker_set.h
index 5db8518c88f..5742ec62558 100644
--- a/sys/sys/linker_set.h
+++ b/sys/sys/linker_set.h
@@ -79,9 +79,9 @@
 /*
  * Initialize before referring to a given linker set.
  */
-#define SET_DECLARE(set, ptype)						\
-	extern ptype *__CONCAT(__start_set_,set);			\
-	extern ptype *__CONCAT(__stop_set_,set)
+#define SET_DECLARE(set, ptype)					\
+	extern ptype __weak *__CONCAT(__start_set_,set);	\
+	extern ptype __weak *__CONCAT(__stop_set_,set)
 
 #define SET_BEGIN(set)							\
 	(&__CONCAT(__start_set_,set))