diff --git a/simulator/port_tree.cpp b/simulator/port_tree.cpp
index 84d5bf4..24eebca 100644
--- a/simulator/port_tree.cpp
+++ b/simulator/port_tree.cpp
@@ -132,21 +132,21 @@ void port_tree::set_priority (uint32_t priority)
 
 uint32_t port_tree::internal_port_path_cost() const
 {
-	return STP_GetInternalPortPathCost(_port->bridge()->stp_bridge(), _port->port_index(), _tree_index);
+	return STP_GetInternalPortPathCost(_port->bridge()->stp_bridge(), (unsigned int)_port->port_index(), (unsigned int)_tree_index);
 }
 
 uint32_t port_tree::admin_internal_port_path_cost() const
 {
-	return STP_GetAdminInternalPortPathCost(_port->bridge()->stp_bridge(), _port->port_index(), _tree_index);
+	return STP_GetAdminInternalPortPathCost(_port->bridge()->stp_bridge(), (unsigned int)_port->port_index(), (unsigned int)_tree_index);
 }
 
 void port_tree::set_admin_internal_port_path_cost (uint32_t value)
 {
-	if (STP_GetAdminInternalPortPathCost (_port->bridge()->stp_bridge(), _port->port_index(), _tree_index) != value)
+	if (STP_GetAdminInternalPortPathCost (_port->bridge()->stp_bridge(), (unsigned int)_port->port_index(), (unsigned int)_tree_index) != value)
 	{
 		this->on_property_changing (&admin_internal_port_path_cost_property);
 		this->on_property_changing (&internal_port_path_cost_property);
-		STP_SetAdminInternalPortPathCost (_port->bridge()->stp_bridge(), _port->port_index(), _tree_index, value, ::GetMessageTime());
+		STP_SetAdminInternalPortPathCost (_port->bridge()->stp_bridge(), (unsigned int)_port->port_index(), (unsigned int)_tree_index, value, ::GetMessageTime());
 		this->on_property_changed (&internal_port_path_cost_property);
 		this->on_property_changed (&admin_internal_port_path_cost_property);
 	}
diff --git a/tests/test_helpers.cpp b/tests/test_helpers.cpp
index c4610dd..60f4c75 100644
--- a/tests/test_helpers.cpp
+++ b/tests/test_helpers.cpp
@@ -95,14 +95,14 @@ bool exchange_bpdus (test_bridge& one, size_t one_port, test_bridge& other, size
 		{
 			auto bpdu = std::move(one.tx_queues[one_port].back());
 			one.tx_queues[one_port].pop();
-			STP_OnBpduReceived (other, other_port, bpdu.data(), (unsigned int) bpdu.size(), 0);
+			STP_OnBpduReceived (other, (unsigned int)other_port, bpdu.data(), (unsigned int) bpdu.size(), 0);
 			exchanged = true;
 		}
 		else if (!other.tx_queues[other_port].empty())
 		{
 			auto bpdu = std::move(other.tx_queues[other_port].back());
 			other.tx_queues[other_port].pop();
-			STP_OnBpduReceived (one, one_port, bpdu.data(), (unsigned int) bpdu.size(), 0);
+			STP_OnBpduReceived (one, (unsigned int)one_port, bpdu.data(), (unsigned int) bpdu.size(), 0);
 			exchanged = true;
 		}
 		else