diff --git a/libcxx/include/__config b/libcxx/include/__config
index 67d2fd7a3e1b5..a6ed5c69a47bd 100644
--- a/libcxx/include/__config
+++ b/libcxx/include/__config
@@ -881,6 +881,10 @@ typedef unsigned int   char32_t;
 #  endif
 #endif
 
+#ifndef _LIBCPP_DEBUG_LEVEL
+# define _LIBCPP_DEBUG_LEVEL 0
+#endif
+
 #ifdef _LIBCPP_DISABLE_EXTERN_TEMPLATE
 #define _LIBCPP_EXTERN_TEMPLATE(...)
 #define _LIBCPP_EXTERN_TEMPLATE2(...)
@@ -1254,6 +1258,14 @@ _LIBCPP_FUNC_VIS extern "C" void __sanitizer_annotate_contiguous_container(
 #  endif
 #endif
 
+#ifndef _LIBCPP_THREAD_SAFETY_ANNOTATION
+#  ifdef _LIBCPP_HAS_THREAD_SAFETY_ANNOTATIONS
+#    define _LIBCPP_THREAD_SAFETY_ANNOTATION(x) __attribute__((x))
+#  else
+#    define _LIBCPP_THREAD_SAFETY_ANNOTATION(x)
+#  endif
+#endif  // _LIBCPP_THREAD_SAFETY_ANNOTATION
+
 #if __has_attribute(require_constant_initialization)
 #  define _LIBCPP_SAFE_STATIC __attribute__((__require_constant_initialization__))
 #else
diff --git a/libcxx/include/__mutex_base b/libcxx/include/__mutex_base
index ed75c82380a6c..8b4b74802b194 100644
--- a/libcxx/include/__mutex_base
+++ b/libcxx/include/__mutex_base
@@ -29,15 +29,6 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 
 #ifndef _LIBCPP_HAS_NO_THREADS
 
-#ifndef _LIBCPP_THREAD_SAFETY_ANNOTATION
-#  ifdef _LIBCPP_HAS_THREAD_SAFETY_ANNOTATIONS
-#    define _LIBCPP_THREAD_SAFETY_ANNOTATION(x) __attribute__((x))
-#  else
-#    define _LIBCPP_THREAD_SAFETY_ANNOTATION(x)
-#  endif
-#endif  // _LIBCPP_THREAD_SAFETY_ANNOTATION
-
-
 class _LIBCPP_TYPE_VIS _LIBCPP_THREAD_SAFETY_ANNOTATION(capability("mutex")) mutex
 {
     __libcpp_mutex_t __m_ = _LIBCPP_MUTEX_INITIALIZER;