diff -ur Random123-1.13.2.orig/include/Random123/uniform.hpp Random123-1.13.2/include/Random123/uniform.hpp
--- Random123-1.13.2.orig/include/Random123/uniform.hpp	2020-02-23 13:48:36.738627640 +0000
+++ Random123-1.13.2/include/Random123/uniform.hpp	2020-02-23 13:48:59.490040126 +0000
@@ -87,6 +87,7 @@
 
 #include <Random123/features/compilerfeatures.h>
 #include <limits>
+#include <cstddef>
 #if R123_USE_CXX11_TYPE_TRAITS
 #include <type_traits>
 #endif