diff --git a/route_info_aix.go b/route_info_aix.go
index ee8e7984..4e23d9d4 100644
--- a/route_info_aix.go
+++ b/route_info_aix.go
@@ -1,3 +1,5 @@
+//go:build aix
+
 package sockaddr
 
 import (
@@ -9,10 +11,6 @@ var cmds map[string][]string = map[string][]string{
 	"route": {"/usr/sbin/route", "-n", "get", "default"},
 }
 
-type routeInfo struct {
-	cmds map[string][]string
-}
-
 // NewRouteInfo returns a BSD-specific implementation of the RouteInfo
 // interface.
 func NewRouteInfo() (routeInfo, error) {
diff --git a/route_info_solaris.go b/route_info_solaris.go
index 5843d58c..1354a73b 100644
--- a/route_info_solaris.go
+++ b/route_info_solaris.go
@@ -1,3 +1,5 @@
+//go:build solaris
+
 package sockaddr
 
 import (