diff --git a/mps/test/argerr/42.c b/mps/test/argerr/42.c
index cfc5acac794..6c25c1aa4f3 100644
--- a/mps/test/argerr/42.c
+++ b/mps/test/argerr/42.c
@@ -21,12 +21,9 @@ static void test(void)
 {
  mps_arena_t arena;
  mps_pool_t pool;
- mps_thr_t thread;
 
  cdie(mps_arena_create(&arena, mps_arena_class_vm(), mmqaArenaSIZE), "create arena");
 
- cdie(mps_thread_reg(&thread, arena), "register thread");
-
  cdie(
   mps_pool_create(
      &pool, arena, mps_class_mv(),
@@ -34,7 +31,7 @@ static void test(void)
   "create pool");
 
  mps_pool_destroy(pool);
-
+ mps_arena_destroy(arena);
 }
 
 int main(void)
diff --git a/mps/test/argerr/43.c b/mps/test/argerr/43.c
index 7e68227aaa6..2ab28815fe4 100644
--- a/mps/test/argerr/43.c
+++ b/mps/test/argerr/43.c
@@ -34,7 +34,8 @@ static void test(void)
   "create pool");
 
  mps_pool_destroy(pool);
-
+ mps_thread_dereg(thread);
+ mps_arena_destroy(arena);
 }
 
 int main(void)