--- libgo/go/syscall/route_bsdsunix.go.orig	2020-03-04 19:30:03.000000000 +1100
+++ libgo/go/syscall/route_bsdsunix.go	2020-09-22 00:20:28.672028000 +1000
@@ -0,0 +1,106 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package syscall
+
+import "unsafe"
+
+// See http://www.bsdsunix.org/doc/en/books/porters-handbook/bsdsunix-versions.html.
+var bsdsunixVersion uint32
+
+func init() {
+	bsdsunixVersion, _ = SysctlUint32("kern.osreldate")
+	conf, _ := Sysctl("kern.conftxt")
+	for i, j := 0, 0; j < len(conf); j++ {
+		if conf[j] != '\n' {
+			continue
+		}
+		s := conf[i:j]
+		i = j + 1
+		if len(s) > len("machine") && s[:len("machine")] == "machine" {
+			s = s[len("machine"):]
+			for k := 0; k < len(s); k++ {
+				if s[k] == ' ' || s[k] == '\t' {
+					s = s[1:]
+				}
+				break
+			}
+			bsdsunixConfArch = s
+			break
+		}
+	}
+}
+
+func (any *anyMessage) toRoutingMessage(b []byte) RoutingMessage {
+	switch any.Type {
+	case RTM_ADD, RTM_DELETE, RTM_CHANGE, RTM_GET, RTM_LOSING, RTM_REDIRECT, RTM_MISS, RTM_LOCK, RTM_RESOLVE:
+		return any.parseRouteMessage(b)
+	case RTM_IFINFO:
+		return any.parseInterfaceMessage(b)
+	case RTM_IFANNOUNCE:
+		p := (*InterfaceAnnounceMessage)(unsafe.Pointer(any))
+		return &InterfaceAnnounceMessage{Header: p.Header}
+	case RTM_NEWADDR, RTM_DELADDR:
+		p := (*InterfaceAddrMessage)(unsafe.Pointer(any))
+		return &InterfaceAddrMessage{Header: p.Header, Data: b[SizeofIfaMsghdr:any.Msglen]}
+	case RTM_NEWMADDR, RTM_DELMADDR:
+		p := (*InterfaceMulticastAddrMessage)(unsafe.Pointer(any))
+		return &InterfaceMulticastAddrMessage{Header: p.Header, Data: b[SizeofIfmaMsghdr:any.Msglen]}
+	}
+	return nil
+}
+
+// InterfaceAnnounceMessage represents a routing message containing
+// network interface arrival and departure information.
+//
+// Deprecated: Use golang.org/x/net/route instead.
+type InterfaceAnnounceMessage struct {
+	Header IfAnnounceMsghdr
+}
+
+func (m *InterfaceAnnounceMessage) sockaddr() ([]Sockaddr, error) { return nil, nil }
+
+// InterfaceMulticastAddrMessage represents a routing message
+// containing network interface address entries.
+//
+// Deprecated: Use golang.org/x/net/route instead.
+type InterfaceMulticastAddrMessage struct {
+	Header IfmaMsghdr
+	Data   []byte
+}
+
+func (m *InterfaceMulticastAddrMessage) sockaddr() ([]Sockaddr, error) {
+	var sas [RTAX_MAX]Sockaddr
+	b := m.Data[:]
+	for i := uint(0); i < RTAX_MAX && len(b) >= minRoutingSockaddrLen; i++ {
+		if m.Header.Addrs&(1<<i) == 0 {
+			continue
+		}
+		rsa := (*RawSockaddr)(unsafe.Pointer(&b[0]))
+		switch rsa.Family {
+		case AF_LINK:
+			sa, err := parseSockaddrLink(b)
+			if err != nil {
+				return nil, err
+			}
+			sas[i] = sa
+			b = b[rsaAlignOf(int(rsa.Len)):]
+		case AF_INET, AF_INET6:
+			sa, err := parseSockaddrInet(b, rsa.Family)
+			if err != nil {
+				return nil, err
+			}
+			sas[i] = sa
+			b = b[rsaAlignOf(int(rsa.Len)):]
+		default:
+			sa, l, err := parseLinkLayerAddr(b)
+			if err != nil {
+				return nil, err
+			}
+			sas[i] = sa
+			b = b[l:]
+		}
+	}
+	return sas[:], nil
+}