1 files changed, 1 insertions, 0 deletions
diff --git a/enum.c b/enum.c
index ad34004081..9f74e77e88 100644
--- a/enum.c
+++ b/enum.c
@@ -9,6 +9,7 @@
 
 **********************************************************************/
 
+#include "ruby/encoding.h"
 #include "internal.h"
 #include "ruby/util.h"
 #include "id.h"