diff --git a/libc/private/bionic_globals.h b/libc/private/bionic_globals.h
index 8ea7d4d..08a61f0 100644
--- a/libc/private/bionic_globals.h
+++ b/libc/private/bionic_globals.h
@@ -50,6 +50,7 @@
   uintptr_t heap_pointer_tag;
   _Atomic(bool) memtag_stack;
   _Atomic(bool) decay_time_enabled;
+  _Atomic(bool) memtag;
 
   // In order to allow a complete switch between dispatch tables without
   // the need for copying each function by function in the structure,
@@ -135,6 +136,8 @@
   HeapTaggingLevel initial_heap_tagging_level = M_HEAP_TAGGING_LEVEL_NONE;
   bool initial_memtag_stack = false;
   int64_t heap_tagging_upgrade_timer_sec = 0;
+
+  void (*memtag_stack_dlopen_callback)() = nullptr;
 };
 
 __LIBC_HIDDEN__ libc_shared_globals* __libc_shared_globals();