diff --git a/contrib/oid2name/oid2name.c b/contrib/oid2name/oid2name.c
index 565baea1b63..9169c9fd243 100644
--- a/contrib/oid2name/oid2name.c
+++ b/contrib/oid2name/oid2name.c
@@ -6,6 +6,7 @@
 
  */
 
+#include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <string.h>