diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 36149efdf27..a9b95b1d61b 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,7 @@
+2008-12-12  Benjamin Kosnik  <bkoz@redhat.com>
+
+	* src/atomic.cc: Correct guards to match mutex.cc.
+
 2008-12-11  Benjamin Kosnik  <bkoz@redhat.com>
 	    Richard Henderson  <rth@redhat.com>
 
diff --git a/libstdc++-v3/src/atomic.cc b/libstdc++-v3/src/atomic.cc
index e2fe68f09bc..9e6444dcfe3 100644
--- a/libstdc++-v3/src/atomic.cc
+++ b/libstdc++-v3/src/atomic.cc
@@ -36,7 +36,7 @@
 
 namespace
 {
-#ifdef _GLIBCXX_HAS_GTHREADS
+#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
   std::mutex atomic_mutex;
 #endif
 
@@ -56,7 +56,7 @@ namespace std
     bool
     atomic_flag::test_and_set(memory_order) volatile
     {
-#ifdef _GLIBCXX_HAS_GTHREADS
+#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
       lock_guard<mutex> __lock(atomic_mutex);
 #endif
       bool result = _M_i;
@@ -67,7 +67,7 @@ namespace std
     void
     atomic_flag::clear(memory_order) volatile
     {
-#ifdef _GLIBCXX_HAS_GTHREADS
+#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
       lock_guard<mutex> __lock(atomic_mutex);
 #endif
       _M_i = false;