diff --git a/newlib/libc/include/sys/cdefs.h b/newlib/libc/include/sys/cdefs.h
index b3f8d1965..49be9e062 100644
--- a/newlib/libc/include/sys/cdefs.h
+++ b/newlib/libc/include/sys/cdefs.h
@@ -314,7 +314,7 @@
 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
     __has_extension(cxx_static_assert)
 #define	_Static_assert(x, y)	static_assert(x, y)
-#elif __GNUC_PREREQ__(4,6)
+#elif __GNUC_PREREQ__(4,6) && !defined(__cplusplus)
 /* Nothing, gcc 4.6 and higher has _Static_assert built-in */
 #elif defined(__COUNTER__)
 #define	_Static_assert(x, y)	__Static_assert(x, __COUNTER__)