diff --git a/callouts/nm-dispatcher-utils.c b/callouts/nm-dispatcher-utils.c
index d8a8e8d87c..e7a6f6a2e6 100644
--- a/callouts/nm-dispatcher-utils.c
+++ b/callouts/nm-dispatcher-utils.c
@@ -377,7 +377,7 @@ nm_dispatcher_utils_construct_envp (const char *action,
 			return NULL;
 		}
 		g_variant_unref (value);
-		g_variant_lookup (device_props, NMD_DEVICE_PROPS_IP_INTERFACE, "&s", &ip_iface);
+		(void) g_variant_lookup (device_props, NMD_DEVICE_PROPS_IP_INTERFACE, "&s", &ip_iface);
 	}
 
 	/* Device type */
diff --git a/libnm/nm-vpn-plugin-old.c b/libnm/nm-vpn-plugin-old.c
index e6843f7e18..b43c481c7f 100644
--- a/libnm/nm-vpn-plugin-old.c
+++ b/libnm/nm-vpn-plugin-old.c
@@ -279,8 +279,8 @@ nm_vpn_plugin_old_set_config (NMVpnPluginOld *plugin,
 
 	priv->got_config = TRUE;
 
-	g_variant_lookup (config, NM_VPN_PLUGIN_CONFIG_HAS_IP4, "b", &priv->has_ip4);
-	g_variant_lookup (config, NM_VPN_PLUGIN_CONFIG_HAS_IP6, "b", &priv->has_ip6);
+	(void) g_variant_lookup (config, NM_VPN_PLUGIN_CONFIG_HAS_IP4, "b", &priv->has_ip4);
+	(void) g_variant_lookup (config, NM_VPN_PLUGIN_CONFIG_HAS_IP6, "b", &priv->has_ip6);
 
 	g_warn_if_fail (priv->has_ip4 || priv->has_ip6);
 
@@ -288,13 +288,13 @@ nm_vpn_plugin_old_set_config (NMVpnPluginOld *plugin,
 	 * ip4config, for compatibility with older daemons.
 	 */
 	g_clear_pointer (&priv->banner, g_free);
-	g_variant_lookup (config, NM_VPN_PLUGIN_CONFIG_BANNER, "&s", &priv->banner);
+	(void) g_variant_lookup (config, NM_VPN_PLUGIN_CONFIG_BANNER, "&s", &priv->banner);
 	g_clear_pointer (&priv->tundev, g_free);
-	g_variant_lookup (config, NM_VPN_PLUGIN_CONFIG_TUNDEV, "&s", &priv->tundev);
+	(void) g_variant_lookup (config, NM_VPN_PLUGIN_CONFIG_TUNDEV, "&s", &priv->tundev);
 	g_clear_pointer (&priv->gateway, g_free);
-	g_variant_lookup (config, NM_VPN_PLUGIN_CONFIG_EXT_GATEWAY, "&s", &priv->gateway);
+	(void) g_variant_lookup (config, NM_VPN_PLUGIN_CONFIG_EXT_GATEWAY, "&s", &priv->gateway);
 	g_clear_pointer (&priv->mtu, g_free);
-	g_variant_lookup (config, NM_VPN_PLUGIN_CONFIG_MTU, "&s", &priv->mtu);
+	(void) g_variant_lookup (config, NM_VPN_PLUGIN_CONFIG_MTU, "&s", &priv->mtu);
 
 	g_signal_emit (plugin, signals[CONFIG], 0, config);
 }