diff --git a/libgcc/ChangeLog b/libgcc/ChangeLog
index 6fd8b8e0ca68..611223ab645e 100644
--- a/libgcc/ChangeLog
+++ b/libgcc/ChangeLog
@@ -1,3 +1,8 @@
+2015-04-15  Chen Gang  <gang.chen.5i5j@gmail.com>
+
+	* gthr-single.h (__GTHREAD_MUTEX_INIT_FUNCTION): Use empty
+	do-while loop as macro body to avoid warnings.
+
 2015-04-10  Jakub Jelinek  <jakub@redhat.com>
 	    Iain Sandoe  <iain@codesourcery.com>
 
diff --git a/libgcc/gthr-single.h b/libgcc/gthr-single.h
index bddded4f24e7..00b3fd661bb7 100644
--- a/libgcc/gthr-single.h
+++ b/libgcc/gthr-single.h
@@ -35,7 +35,7 @@ typedef int __gthread_recursive_mutex_t;
 
 #define __GTHREAD_ONCE_INIT 0
 #define __GTHREAD_MUTEX_INIT 0
-#define __GTHREAD_MUTEX_INIT_FUNCTION(mx)
+#define __GTHREAD_MUTEX_INIT_FUNCTION(mx) do {} while (0)
 #define __GTHREAD_RECURSIVE_MUTEX_INIT 0
 
 #define UNUSED __attribute__((__unused__))