diff --git a/libgo/configure b/libgo/configure
index d9915f91afc..c1ee7bac082 100755
--- a/libgo/configure
+++ b/libgo/configure
@@ -13818,9 +13818,9 @@ case "$target" in
 	;;
     *-*-solaris2.1[01])
 	# Solaris 10+ needs this so struct msghdr gets the msg_control
-	# etc. fields in <sys/socket.h> (_XPG4_2).  _XOPEN_SOURCE=500 as
+	# etc. fields in <sys/socket.h> (_XPG4_2).  _XOPEN_SOURCE=600 as
 	# above doesn't work with C99.
-	OSCFLAGS="$OSCFLAGS -D_XOPEN_SOURCE=600 -D__EXTENSIONS__"
+	OSCFLAGS="$OSCFLAGS -std=gnu99 -D_XOPEN_SOURCE=600 -D__EXTENSIONS__"
 	;;
 esac
 
diff --git a/libgo/configure.ac b/libgo/configure.ac
index a001d50b58a..a56106eaca9 100644
--- a/libgo/configure.ac
+++ b/libgo/configure.ac
@@ -292,9 +292,9 @@ case "$target" in
 	;;
     *-*-solaris2.1[[01]])
 	# Solaris 10+ needs this so struct msghdr gets the msg_control
-	# etc. fields in <sys/socket.h> (_XPG4_2).  _XOPEN_SOURCE=500 as
+	# etc. fields in <sys/socket.h> (_XPG4_2).  _XOPEN_SOURCE=600 as
 	# above doesn't work with C99.
-	OSCFLAGS="$OSCFLAGS -D_XOPEN_SOURCE=600 -D__EXTENSIONS__"
+	OSCFLAGS="$OSCFLAGS -std=gnu99 -D_XOPEN_SOURCE=600 -D__EXTENSIONS__"
 	;;
 esac
 AC_SUBST(OSCFLAGS)