doc: fix the compile fix of txtimestamp.c
A fix to ipv6 structure definitions removed the now superfluous
definition of in6_pktinfo in this file.
But, use of the glibc definition requires defining _GNU_SOURCE
(see also https://sourceware.org/bugzilla/show_bug.cgi?id=6775).
Before this change, the following would fail for me:
make
make headers_install
make M=Documentation/networking/timestamping
with
Documentation/networking/timestamping/txtimestamp.c: In function '__recv_errmsg_cmsg':
Documentation/networking/timestamping/txtimestamp.c:205:33: error: dereferencing pointer to incomplete type
Documentation/networking/timestamping/txtimestamp.c:206:23: error: dereferencing pointer to incomplete type
After this patch compilation succeeded.
Fixes: cd91cc5bdddf ("doc: fix the compile error of txtimestamp.c")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/Documentation/networking/timestamping/txtimestamp.c b/Documentation/networking/timestamping/txtimestamp.c
index 8778e68..05694fe 100644
--- a/Documentation/networking/timestamping/txtimestamp.c
+++ b/Documentation/networking/timestamping/txtimestamp.c
@@ -30,6 +30,8 @@
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*/
+#define _GNU_SOURCE
+
#include <arpa/inet.h>
#include <asm/types.h>
#include <error.h>