diff --git a/src/network/utils/queue-size.h b/src/network/utils/queue-size.h
index a4f3fd880..bdf745caf 100644
--- a/src/network/utils/queue-size.h
+++ b/src/network/utils/queue-size.h
@@ -39,7 +39,7 @@ namespace ns3 {
  * \brief Enumeration of the operating modes of queues.
  *
  */
-enum class QueueSizeUnit : uint8_t
+enum QueueSizeUnit
 {
   PACKETS,     /**< Use number of packets for queue size */
   BYTES,       /**< Use number of bytes for queue size */
diff --git a/src/traffic-control/model/queue-disc.h b/src/traffic-control/model/queue-disc.h
index e93734cb9..6469f8bec 100644
--- a/src/traffic-control/model/queue-disc.h
+++ b/src/traffic-control/model/queue-disc.h
@@ -100,7 +100,7 @@ private:
  * internal queue/child queue disc because of lack of space, while the queue
  * disc limit is not exceeded.
  */
-enum class QueueDiscSizePolicy : uint8_t
+enum QueueDiscSizePolicy
 {
   SINGLE_INTERNAL_QUEUE,       /**< Used by queue discs with single internal queue */
   SINGLE_CHILD_QUEUE_DISC,     /**< Used by queue discs with single child queue disc */