diff --git a/configure.in b/configure.in
index 58ea9484eb2d6c52c95ea895e91007d90c14de3a..395c09984af36f8c504ec54d0c3981eb2ac42db1 100644
--- a/configure.in
+++ b/configure.in
@@ -446,7 +446,7 @@ AC_CHECK_TYPES([struct in6_addr, struct sockaddr_in6, sa_family_t], , ,
 #endif
 #endif
 ])
-AC_CHECK_MEMBERS([struct in6_addr.s6_addr32, struct in6_addr.s6_addr16], , ,
+AC_CHECK_MEMBERS([struct in6_addr.s6_addr32, struct in6_addr.s6_addr16, struct sockaddr_in.sin_len, struct sockaddr_in6.sin6_len], , ,
 [#ifdef HAVE_SYS_TYPES_H
 #include <sys/types.h>
 #endif
diff --git a/src/common/address.c b/src/common/address.c
index 1abd1a7dfb8d581f66344c8882f84a939a7f1517..2dd763da99f7da942011534b14e6d1b32e4c828f 100644
--- a/src/common/address.c
+++ b/src/common/address.c
@@ -69,7 +69,9 @@ tor_addr_to_sockaddr(const tor_addr_t *a,
       return -1;
     sin = (struct sockaddr_in *)sa_out;
     memset(sin, 0, sizeof(struct sockaddr_in));
+#ifdef HAVE_STRUCT_SOCKADDR_IN_SIN_LEN
     sin->sin_len = sizeof(struct sockaddr_in);
+#endif
     sin->sin_family = AF_INET;
     sin->sin_port = htons(port);
     sin->sin_addr.s_addr = tor_addr_to_ipv4n(a);
@@ -80,7 +82,9 @@ tor_addr_to_sockaddr(const tor_addr_t *a,
       return -1;
     sin6 = (struct sockaddr_in6 *)sa_out;
     memset(sin6, 0, sizeof(struct sockaddr_in6));
+#ifdef HAVE_STRUCT_SOCKADDR_IN6_SIN6_LEN
     sin6->sin6_len = sizeof(struct sockaddr_in6);
+#endif
     sin6->sin6_family = AF_INET6;
     sin6->sin6_port = htons(port);
     memcpy(&sin6->sin6_addr, tor_addr_to_in6(a), sizeof(struct in6_addr));
diff --git a/src/or/eventdns.c b/src/or/eventdns.c
index 248422d22adc503baf675733a3c7b9c3bd3216b0..6b6175821018fb7ff099faebe4a7091a57915cb7 100644
--- a/src/or/eventdns.c
+++ b/src/or/eventdns.c
@@ -2302,7 +2302,9 @@ evdns_nameserver_add(unsigned long int address) {
 	struct sockaddr_in sin;
 	memset(&sin, 0, sizeof(sin));
 	sin.sin_family = AF_INET;
+#ifdef HAVE_STRUCT_SOCKADDR_IN_SIN_LEN
 	sin.sin_len = sizeof(sin);
+#endif
 	sin.sin_addr.s_addr = htonl(address);
 	sin.sin_port = 53;
 	return _evdns_nameserver_add_impl((struct sockaddr*) &sin, sizeof(sin));
@@ -2381,7 +2383,9 @@ evdns_nameserver_ip_add(const char *ip_as_string) {
 	if (is_ipv6) {
 		struct sockaddr_in6 sin6;
 		memset(&sin6, 0, sizeof(sin6));
+#ifdef HAVE_STRUCT_SOCKADDR_IN6_SIN6_LEN
 		sin6.sin6_len = sizeof(sin6);
+#endif
 		sin6.sin6_family = AF_INET6;
 		sin6.sin6_port = htons(port);
 		if (1 != tor_inet_pton(AF_INET6, addr_part, &sin6.sin6_addr)) {
@@ -2393,7 +2397,9 @@ evdns_nameserver_ip_add(const char *ip_as_string) {
 	} else {
 		struct sockaddr_in sin;
 		memset(&sin, 0, sizeof(sin));
+#ifdef HAVE_STRUCT_SOCKADDR_IN_SIN_LEN
 		sin.sin_len = sizeof(sin);
+#endif
 		sin.sin_family = AF_INET;
 		sin.sin_port = htons(port);
 		if (!inet_aton(addr_part, &sin.sin_addr)) {