diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index e2cfdaf9f4dc..7de6bcef4e88 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,7 @@
+2010-11-02  Jason Merrill  <jason@redhat.com>
+
+	* include/bits/atomic_0.h (_ATOMIC_CMPEXCHNG_): Use C-style cast.
+
 2010-11-02  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
 
 	PR target/45693
diff --git a/libstdc++-v3/include/bits/atomic_0.h b/libstdc++-v3/include/bits/atomic_0.h
index cd73e43caefa..8daf4160bad5 100644
--- a/libstdc++-v3/include/bits/atomic_0.h
+++ b/libstdc++-v3/include/bits/atomic_0.h
@@ -98,7 +98,7 @@ namespace __atomic0
     __i_type __t = *__p;		       				   \
     if (*__q == __t) 							   \
     {                                                                      \
-      *__p = const_cast<__i_type>(__v);	 				   \
+      *__p = (__i_type)__v;						\
       __r = true;                                                          \
     }									   \
     else { *__q = __t; __r = false; }		       			   \