diff --git a/include/mruby/irep.h b/include/mruby/irep.h
index 1719866c8..ab0b125c3 100644
--- a/include/mruby/irep.h
+++ b/include/mruby/irep.h
@@ -20,7 +20,7 @@ enum irep_pool_type {
   IREP_TT_SSTR = 2,   /* string (static) */
   IREP_TT_INT32 = 1,  /* 32-bit integer */
   IREP_TT_INT64 = 3,  /* 64-bit integer */
-  IREP_TT_BIGINT = 7, /* big integer (not yet supported) */
+  IREP_TT_BIGINT = 7, /* big integer */
   IREP_TT_FLOAT = 5,  /* float (double/float) */
 };