diff --git a/CUtils/CUtils.xs b/CUtils/CUtils.xs
index d550406d7e84cc949b3e09c7602bad3e1fa86116..2ae99dd877ae287ef2254f60f70710ab9dff608a 100644
--- a/CUtils/CUtils.xs
+++ b/CUtils/CUtils.xs
@@ -9,6 +9,7 @@
 #include "double_permutation.h"
 #include "resampling.h"
 #include "stats.h"
+#include "rhyper.h"
 
 #include "const-c.inc"