diff --git a/src/lj_carith.c b/src/lj_carith.c
index 9f3208a8..a93ec685 100644
--- a/src/lj_carith.c
+++ b/src/lj_carith.c
@@ -337,11 +337,11 @@ uint64_t lj_carith_check64(lua_State *L, int narg, CTypeID *id)
     goto err;
   }
   if (LJ_LIKELY(tvisint(o))) {
-    return intV(o);
+    return (uint32_t)intV(o);
   } else {
     int32_t i = lj_num2bit(numV(o));
     if (LJ_DUALNUM) setintV(o, i);
-    return i;
+    return (uint32_t)i;
   }
 }