net: vrf: avoid gcc-4.6 warning

Message ID 20170912201100.3680915-1-arnd@arndb.de
State Accepted
Commit ecf091171b70787f92b18eeaa4ddc74f9221fa56
Headers show
Series
  • net: vrf: avoid gcc-4.6 warning
Related show

Commit Message

Arnd Bergmann Sept. 12, 2017, 8:10 p.m.
When building an allmodconfig kernel with gcc-4.6, we get a rather
odd warning:

drivers/net/vrf.c: In function ‘vrf_ip6_input_dst’:
drivers/net/vrf.c:964:3: error: initialized field with side-effects overwritten [-Werror]
drivers/net/vrf.c:964:3: error: (near initialization for ‘fl6’) [-Werror]

I have no idea what this warning is even trying to say, but it does
seem like a false positive. Reordering the initialization in to match
the structure definition gets rid of the warning, and might also avoid
whatever gcc thinks is wrong here.

Fixes: 9ff74384600a ("net: vrf: Handle ipv6 multicast and link-local addresses")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

---
 drivers/net/vrf.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

-- 
2.9.0

Comments

David Miller Sept. 15, 2017, 9:22 p.m. | #1
From: Arnd Bergmann <arnd@arndb.de>

Date: Tue, 12 Sep 2017 22:10:53 +0200

> When building an allmodconfig kernel with gcc-4.6, we get a rather

> odd warning:

> 

> drivers/net/vrf.c: In function ‘vrf_ip6_input_dst’:

> drivers/net/vrf.c:964:3: error: initialized field with side-effects overwritten [-Werror]

> drivers/net/vrf.c:964:3: error: (near initialization for ‘fl6’) [-Werror]

> 

> I have no idea what this warning is even trying to say, but it does

> seem like a false positive. Reordering the initialization in to match

> the structure definition gets rid of the warning, and might also avoid

> whatever gcc thinks is wrong here.

> 

> Fixes: 9ff74384600a ("net: vrf: Handle ipv6 multicast and link-local addresses")

> Signed-off-by: Arnd Bergmann <arnd@arndb.de>


That's extremely weird, I can't explain it either.

Oh well, applied, thanks.

Patch

diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c
index 7e19051f3230..9b243e6f3008 100644
--- a/drivers/net/vrf.c
+++ b/drivers/net/vrf.c
@@ -957,12 +957,12 @@  static void vrf_ip6_input_dst(struct sk_buff *skb, struct net_device *vrf_dev,
 {
 	const struct ipv6hdr *iph = ipv6_hdr(skb);
 	struct flowi6 fl6 = {
+		.flowi6_iif     = ifindex,
+		.flowi6_mark    = skb->mark,
+		.flowi6_proto   = iph->nexthdr,
 		.daddr          = iph->daddr,
 		.saddr          = iph->saddr,
 		.flowlabel      = ip6_flowinfo(iph),
-		.flowi6_mark    = skb->mark,
-		.flowi6_proto   = iph->nexthdr,
-		.flowi6_iif     = ifindex,
 	};
 	struct net *net = dev_net(vrf_dev);
 	struct rt6_info *rt6;