fix precedence

Author: TheNumbat

middle_end/flambda2/to_cmm/to_cmm_static.ml

@@ -266,7 +266,8 @@ let static_const0 env res ~updates (bound_static : Bound_static.Pattern.t)
     assert (Arch.size_int = 8);
     immutable_unboxed_int_array env res updates Int32 ~symbol ~elts
       ~to_int64:Int64.of_int32 ~custom_ops_symbol:(fun ~num_elts ->
-        "caml_unboxed_int32_array_ops", Some (C.custom_ops_size * num_elts mod 2))
+        ( "caml_unboxed_int32_array_ops",
+          Some (C.custom_ops_size * (num_elts mod 2)) ))
   | Block_like symbol, Immutable_int64_array elts ->
     immutable_unboxed_int_array env res updates Int64_or_nativeint ~symbol ~elts
       ~to_int64:Fun.id ~custom_ops_symbol:(fun ~num_elts:_ ->