https://sourceforge.net/tracker/?func=detail&aid=3173314&group_id=129766&atid=715782
https://bugs.gentoo.org/353733

--- a/src/zmm/object.h
+++ b/src/zmm/object.h
@@ -33,6 +33,7 @@
 #define __ZMM_OBJECT_H__
 
 #include <new> // for size_t
+#include <cstddef>
 #include "atomic.h"
 
 namespace zmm