--- libmalloc/libmalloc-521.100.59/tests/malloc_zone_unregister_test.c
+++ libmalloc/libmalloc-317.100.9/tests/malloc_zone_unregister_test.c
@@ -11,14 +11,13 @@
 #include <malloc/malloc.h>
 #include <stdlib.h>
 
-T_GLOBAL_META(T_META_RUN_CONCURRENTLY(true), T_META_TAG_XZONE);
+T_GLOBAL_META(T_META_RUN_CONCURRENTLY(true));
 
 extern int32_t malloc_num_zones;
 extern malloc_zone_t **malloc_zones;
 
 T_DECL(malloc_zone_unregister_establish_custom_default_zone,
 		"Unregister all initial zones and register a custom default zone",
-		T_META_ENVVAR("MallocProbGuard=0"),
 		T_META_ENVVAR("MallocNanoZone=1"))
 {
   void *ptr = malloc(7);
@@ -59,9 +58,8 @@
 
   // Check that the custom zone is the default zone
   void *ptr2 = malloc(7);
-  T_EXPECT_EQ(malloc_zones[0], custom_zone, "custom zone is zone 0");
-  T_EXPECT_EQ(malloc_zone_from_ptr(ptr2), malloc_default_zone(), "we lookup the virtual zone for the custom zone");
-  T_EXPECT_TRUE(malloc_zone_claimed_address(custom_zone, ptr2), "custom zone claims ptr");
+  T_EXPECT_EQ(malloc_zone_from_ptr(ptr2), custom_zone, "can find custom zone for allocation");
+  T_EXPECT_TRUE(malloc_claimed_address(ptr2), "ptr from custom zone is claimed");
 
   free(ptr2);
   free(ptr);