diff --git a/mps/code/addrobj.c b/mps/code/addrobj.c
index 43d1cd14b92..6c34e833514 100644
--- a/mps/code/addrobj.c
+++ b/mps/code/addrobj.c
@@ -66,7 +66,23 @@ static void test_main(void)
 
   /* Make an arbitrary sized object, size = (N_SLOT_TESTOBJ+2) * sizeof(mps_word_t).
      (See fmtdytst.c for size calculation) */
-  die(make_dylan_vector((mps_word_t *)&testobj, obj_ap, N_SLOT_TESTOBJ), "make_dylan_vector");
+
+  /* Because make_dylan_vector returns its pointer-to-object as an mps_word_t rather than an
+     mps_addr_t, and commits the object, we need to somehow safely allocate our object without
+     type punning and without risking that our object be destroyed.
+     Rather than redefine our reference table with type mps_word_t, which hides the intention of the table,
+     park the arena to disable garbage collection. Allocate our dylan object on the (unregistered) stack
+     storing its address in an mps_word_t. Then store this mps_word_t as an mps_addr_t in our reference
+     table, and release the arena since our object is now safely pinned.
+  */
+  {
+    mps_word_t p_word;
+    mps_arena_park(arena);
+    die(make_dylan_vector(&p_word, obj_ap, N_SLOT_TESTOBJ), "make_dylan_vector");
+    /* If we hadn't parked the arena, our vector might have been GC'd here */
+    testobj = (mps_addr_t)p_word;
+    mps_arena_release(arena);
+  }
 
   /* Construct a pointer to roughly halfway inside the object */
   in = (mps_addr_t)((char *)testobj + (N_SLOT_TESTOBJ/2) * sizeof(mps_word_t));