diff -r 2a1bceb2bd18 libgo/mksysinfo.sh
--- a/libgo/mksysinfo.sh	Wed Jan 25 17:07:11 2012 -0800
+++ b/libgo/mksysinfo.sh	Wed Jan 25 21:41:38 2012 -0800
@@ -192,7 +192,7 @@
   sed -e 's/^\(const \)_\(SHUT[^= ]*\)\(.*\)$/\1\2 = _\2/' >> ${OUT}
 
 # The net package requires some const definitions.
-for m in IPV6_V6ONLY IPPROTO_IPV6 IPV6_JOIN_GROUP IPV6_LEAVE_GROUP; do
+for m in IPV6_V6ONLY IPPROTO_IPV6 IPV6_JOIN_GROUP IPV6_LEAVE_GROUP IPV6_TCLASS; do
   if ! grep "^const $m " ${OUT} >/dev/null 2>&1; then
     echo "const $m = 0" >> ${OUT}
   fi