[PATCH] geneve: Add missing braces in addr6 initializer

[PATCH] geneve: Add missing braces in addr6 initializer

[Nathan Chancellor]

Clang warns:

drivers/net/geneve.c:428:29: error: suggest braces around initialization
of subobject [-Werror,-Wmissing-braces]
                struct in6_addr addr6 = { 0 };
                                          ^
                                          {}

Fixes: a07966447f39 ("geneve: ICMP error lookup handler")
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
---
 drivers/net/geneve.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index 7c53e06b31c3..224d8b0bb5de 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -425,7 +425,7 @@ static int geneve_udp_encap_err_lookup(struct sock *sk, struct sk_buff *skb)
 #if IS_ENABLED(CONFIG_IPV6)
 	if (geneve_get_sk_family(gs) == AF_INET6) {
 		struct ipv6hdr *ip6h = ipv6_hdr(skb);
-		struct in6_addr addr6 = { 0 };
+		struct in6_addr addr6 = { { 0 } };
 
 		if (!gs->collect_md) {
 			vni = geneve_hdr(skb)->vni;
-- 
2.19.1

Re: [PATCH] geneve: Add missing braces in addr6 initializer

[Stefano Brivio]

On Mon, 12 Nov 2018 15:12:48 -0700
Nathan Chancellor <natechancellor@gmail.com> wrote:

> Clang warns:
> 
> drivers/net/geneve.c:428:29: error: suggest braces around initialization
> of subobject [-Werror,-Wmissing-braces]
>                 struct in6_addr addr6 = { 0 };
>                                           ^
>                                           {}
> 
> Fixes: a07966447f39 ("geneve: ICMP error lookup handler")
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

Thanks for spotting this. By the way, I guess you should indicate in
the subject when patches are meant for net-next.

Reviewed-by: Stefano Brivio <sbrivio@redhat.com>

-- 
Stefano

Re: [PATCH] geneve: Add missing braces in addr6 initializer

[Nathan Chancellor]

On Mon, Nov 12, 2018 at 11:19:17PM +0100, Stefano Brivio wrote:
> On Mon, 12 Nov 2018 15:12:48 -0700
> Nathan Chancellor <natechancellor@gmail.com> wrote:
> 
> > Clang warns:
> > 
> > drivers/net/geneve.c:428:29: error: suggest braces around initialization
> > of subobject [-Werror,-Wmissing-braces]
> >                 struct in6_addr addr6 = { 0 };
> >                                           ^
> >                                           {}
> > 
> > Fixes: a07966447f39 ("geneve: ICMP error lookup handler")
> > Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
> 
> Thanks for spotting this. By the way, I guess you should indicate in
> the subject when patches are meant for net-next.
> 

Sure, I'll be better about that in the future.

> Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
> 

Thank you for the review!
Nathan

> -- 
> Stefano

Re: [PATCH] geneve: Add missing braces in addr6 initializer

[Joe Perches]

On Mon, 2018-11-12 at 15:12 -0700, Nathan Chancellor wrote:
> Clang warns:
> 
> drivers/net/geneve.c:428:29: error: suggest braces around initialization
> of subobject [-Werror,-Wmissing-braces]
>                 struct in6_addr addr6 = { 0 };
>                                           ^
>                                           {}

Perhaps just remove the 0.

> diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
[]
> @@ -425,7 +425,7 @@ static int geneve_udp_encap_err_lookup(struct sock *sk, struct sk_buff *skb)
>  #if IS_ENABLED(CONFIG_IPV6)
>  	if (geneve_get_sk_family(gs) == AF_INET6) {
>  		struct ipv6hdr *ip6h = ipv6_hdr(skb);
> -		struct in6_addr addr6 = { 0 };
> +		struct in6_addr addr6 = { { 0 } };
>  
>  		if (!gs->collect_md) {
>  			vni = geneve_hdr(skb)->vni;

[PATCH net-next v2] geneve: Use empty braces for addr6 initializer

[Nathan Chancellor]

Clang warns:

drivers/net/geneve.c:428:29: error: suggest braces around initialization
of subobject [-Werror,-Wmissing-braces]
                struct in6_addr addr6 = { 0 };
                                          ^
                                          {}

Most initializations of structs in the kernel seem to use this format.

Fixes: a07966447f39 ("geneve: ICMP error lookup handler")
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
---

v1 -> v2:

* Just remove the zero instead of adding more braces as it seems to
  match the rest of the kernel (as suggested by Joe Perches).

 drivers/net/geneve.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index 7c53e06b31c3..f09e58b7b01e 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -425,7 +425,7 @@ static int geneve_udp_encap_err_lookup(struct sock *sk, struct sk_buff *skb)
 #if IS_ENABLED(CONFIG_IPV6)
 	if (geneve_get_sk_family(gs) == AF_INET6) {
 		struct ipv6hdr *ip6h = ipv6_hdr(skb);
-		struct in6_addr addr6 = { 0 };
+		struct in6_addr addr6 = { };
 
 		if (!gs->collect_md) {
 			vni = geneve_hdr(skb)->vni;
-- 
2.19.1

Re: [PATCH net-next v2] geneve: Use empty braces for addr6 initializer

[Stefano Brivio]

On Mon, 12 Nov 2018 23:11:47 -0700
Nathan Chancellor <natechancellor@gmail.com> wrote:

> Clang warns:
> 
> drivers/net/geneve.c:428:29: error: suggest braces around initialization
> of subobject [-Werror,-Wmissing-braces]
>                 struct in6_addr addr6 = { 0 };
>                                           ^
>                                           {}
> 
> Most initializations of structs in the kernel seem to use this format.
> 
> Fixes: a07966447f39 ("geneve: ICMP error lookup handler")
> Suggested-by: Joe Perches <joe@perches.com>
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

Also,

Reviewed-by: Stefano Brivio <sbrivio@redhat.com>

-- 
Stefano

Re: [PATCH] geneve: Add missing braces in addr6 initializer

[David Miller]

From: Nathan Chancellor <natechancellor@gmail.com>
Date: Mon, 12 Nov 2018 15:12:48 -0700

> Clang warns:
> 
> drivers/net/geneve.c:428:29: error: suggest braces around initialization
> of subobject [-Werror,-Wmissing-braces]
>                 struct in6_addr addr6 = { 0 };
>                                           ^
>                                           {}
> 
> Fixes: a07966447f39 ("geneve: ICMP error lookup handler")
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

And this makes GCC warn.

drivers/net/geneve.c: In function ‘geneve_udp_encap_err_lookup’:
drivers/net/geneve.c:428:27: warning: missing braces around initializer [-Wmissing-braces]
   struct in6_addr addr6 = { { 0 } };
                           ^
                               { }

（╯°□°）╯︵ ┻━┻

Re: [PATCH] geneve: Add missing braces in addr6 initializer

[Nathan Chancellor]

On Thu, Nov 15, 2018 at 11:35:01AM -0800, David Miller wrote:
> From: Nathan Chancellor <natechancellor@gmail.com>
> Date: Mon, 12 Nov 2018 15:12:48 -0700
> 
> > Clang warns:
> > 
> > drivers/net/geneve.c:428:29: error: suggest braces around initialization
> > of subobject [-Werror,-Wmissing-braces]
> >                 struct in6_addr addr6 = { 0 };
> >                                           ^
> >                                           {}
> > 
> > Fixes: a07966447f39 ("geneve: ICMP error lookup handler")
> > Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
> 
> And this makes GCC warn.
> 
> drivers/net/geneve.c: In function ‘geneve_udp_encap_err_lookup’:
> drivers/net/geneve.c:428:27: warning: missing braces around initializer [-Wmissing-braces]
>    struct in6_addr addr6 = { { 0 } };
>                            ^
>                                { }
> 
> （╯°□°）╯︵ ┻━┻

Yes, sorry, I thought I test built before sending it but apparently not
:( v2 should be sitting in your inbox as a reply to this one unless I
screwed that up too...

Nathan

Re: [PATCH net-next v2] geneve: Use empty braces for addr6 initializer

[Stefano Brivio]

On Mon, 12 Nov 2018 23:11:47 -0700
Nathan Chancellor <natechancellor@gmail.com> wrote:

> Clang warns:
> 
> drivers/net/geneve.c:428:29: error: suggest braces around initialization
> of subobject [-Werror,-Wmissing-braces]
>                 struct in6_addr addr6 = { 0 };
>                                           ^
>                                           {}
> 
> Most initializations of structs in the kernel seem to use this format.

Actually, even with this, we get a warning with gcc 4.4 and 4.8. I tried a
few compilers:

$ gcc-4.4 --version | head -n1
rhel-6.9-gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-18)
$ gcc-4.8 --version | head -n1
rhel-7.5-gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-28)
$ gcc-7.3 --version | head -n1
gcc-7.3-gcc (GCC) 7.3.0
$ gcc-8.2 --version | head -n1
gcc (Debian 8.2.0-9) 8.2.0
$ clang --version | head -n1
clang version 6.0.1-9.2 (tags/RELEASE_601/final)

$ cat init.c
#include <linux/in6.h>
 
int main()
{
        struct in6_addr addr6 = INIT;
 
        return addr6.in6_u.u6_addr8[0];
}

$ gcc-4.4 -DINIT="{ }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
init.c:5: warning: missing initializer
$ gcc-4.4 -DINIT="{ 0 }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
init.c:5: warning: missing braces around initializer
$ gcc-4.4 -DINIT="{ { { 0 } } }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1

$ gcc-4.8 -DINIT="{ }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
init.c:5:16: warning: missing initializer for field 'in6_u' of 'struct in6_addr' [-Wmissing-field-initializers]
$ gcc-4.8 -DINIT="{ 0 }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
init.c:5:16: warning: missing braces around initializer [-Wmissing-braces]
$ gcc-4.8 -DINIT="{ { { 0 } } }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1

$ gcc-7.3 -DINIT="{ }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
$ gcc-7.3 -DINIT="{ 0 }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
$ gcc-7.3 -DINIT="{ { { 0 } } }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1

$ gcc-8.2 -DINIT="{ }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
$ gcc-8.2 -DINIT="{ 0 }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
$ gcc-8.2 -DINIT="{ { { 0 } } }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1

$ clang -DINIT="{ }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
$ clang -DINIT="{ 0 }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
init.c:5:33: warning: suggest braces around initialization of subobject [-Wmissing-braces]
$ clang -DINIT="{ { { 0 } } }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1

So { { { 0 } } } seems to be the safest option. We could go with static
but it looks even uglier to me.

Joe, suggestions?

-- 
Stefano

Re: [PATCH net-next v2] geneve: Use empty braces for addr6 initializer

[Nathan Chancellor]

On Fri, Nov 16, 2018 at 03:04:32PM +0100, Stefano Brivio wrote:
> On Mon, 12 Nov 2018 23:11:47 -0700
> Nathan Chancellor <natechancellor@gmail.com> wrote:
> 
> > Clang warns:
> > 
> > drivers/net/geneve.c:428:29: error: suggest braces around initialization
> > of subobject [-Werror,-Wmissing-braces]
> >                 struct in6_addr addr6 = { 0 };
> >                                           ^
> >                                           {}
> > 
> > Most initializations of structs in the kernel seem to use this format.
> 
> Actually, even with this, we get a warning with gcc 4.4 and 4.8. I tried a
> few compilers:
> 
> $ gcc-4.4 --version | head -n1
> rhel-6.9-gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-18)
> $ gcc-4.8 --version | head -n1
> rhel-7.5-gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-28)
> $ gcc-7.3 --version | head -n1
> gcc-7.3-gcc (GCC) 7.3.0
> $ gcc-8.2 --version | head -n1
> gcc (Debian 8.2.0-9) 8.2.0
> $ clang --version | head -n1
> clang version 6.0.1-9.2 (tags/RELEASE_601/final)
> 
> $ cat init.c
> #include <linux/in6.h>
>  
> int main()
> {
>         struct in6_addr addr6 = INIT;
>  
>         return addr6.in6_u.u6_addr8[0];
> }
> 
> $ gcc-4.4 -DINIT="{ }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
> init.c:5: warning: missing initializer
> $ gcc-4.4 -DINIT="{ 0 }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
> init.c:5: warning: missing braces around initializer
> $ gcc-4.4 -DINIT="{ { { 0 } } }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
> 
> $ gcc-4.8 -DINIT="{ }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
> init.c:5:16: warning: missing initializer for field 'in6_u' of 'struct in6_addr' [-Wmissing-field-initializers]
> $ gcc-4.8 -DINIT="{ 0 }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
> init.c:5:16: warning: missing braces around initializer [-Wmissing-braces]
> $ gcc-4.8 -DINIT="{ { { 0 } } }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
> 
> $ gcc-7.3 -DINIT="{ }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
> $ gcc-7.3 -DINIT="{ 0 }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
> $ gcc-7.3 -DINIT="{ { { 0 } } }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
> 
> $ gcc-8.2 -DINIT="{ }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
> $ gcc-8.2 -DINIT="{ 0 }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
> $ gcc-8.2 -DINIT="{ { { 0 } } }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
> 
> $ clang -DINIT="{ }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
> $ clang -DINIT="{ 0 }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
> init.c:5:33: warning: suggest braces around initialization of subobject [-Wmissing-braces]
> $ clang -DINIT="{ { { 0 } } }" -S -Wall -Wextra -o init init.c 2>&1 | grep warning | head -n1
> 
> So { { { 0 } } } seems to be the safest option. We could go with static
> but it looks even uglier to me.
> 
> Joe, suggestions?
> 
> -- 
> Stefano

Yes, I used the wrong number of braces in the initial patch hence this
one. I'm fine with pushing that change as v3 if everyone agrees that is
fine.

Thanks for looking into this!
Nathan

Re: [PATCH net-next v2] geneve: Use empty braces for addr6 initializer

[David Miller]

From: Stefano Brivio <sbrivio@redhat.com>
Date: Fri, 16 Nov 2018 15:04:32 +0100

> Joe, suggestions?

Let's just memset() this thing already instead of fighting the
compiler(s).

[PATCH net-next v3] geneve: Initialize addr6 with memset

[Nathan Chancellor]

Clang warns:

drivers/net/geneve.c:428:29: error: suggest braces around initialization
of subobject [-Werror,-Wmissing-braces]
                struct in6_addr addr6 = { 0 };
                                          ^
                                          {}

Rather than trying to appease the various compilers that support the
kernel, use memset, which is unambiguous.

Fixes: a07966447f39 ("geneve: ICMP error lookup handler")
Suggested-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
---

v1 -> v2:

* Just remove the zero instead of adding more braces as it seems to
  match the rest of the kernel (as suggested by Joe Perches).

v2 -> v3:

* Use memset as suggested by David Miller.

 drivers/net/geneve.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index 7c53e06b31c3..58bbba8582b0 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -425,7 +425,9 @@ static int geneve_udp_encap_err_lookup(struct sock *sk, struct sk_buff *skb)
 #if IS_ENABLED(CONFIG_IPV6)
 	if (geneve_get_sk_family(gs) == AF_INET6) {
 		struct ipv6hdr *ip6h = ipv6_hdr(skb);
-		struct in6_addr addr6 = { 0 };
+		struct in6_addr addr6;
+
+		memset(&addr6, 0, sizeof(struct in6_addr));
 
 		if (!gs->collect_md) {
 			vni = geneve_hdr(skb)->vni;
-- 
2.19.1

Re: [PATCH net-next v2] geneve: Use empty braces for addr6 initializer

[Joe Perches]

On Fri, 2018-11-16 at 08:37 -0700, Nathan Chancellor wrote:
> On Fri, Nov 16, 2018 at 03:04:32PM +0100, Stefano Brivio wrote:
> > On Mon, 12 Nov 2018 23:11:47 -0700
> > Nathan Chancellor <natechancellor@gmail.com> wrote:
> > 
> > > Clang warns:
> > > 
> > > drivers/net/geneve.c:428:29: error: suggest braces around initialization
> > > of subobject [-Werror,-Wmissing-braces]
> > >                 struct in6_addr addr6 = { 0 };
> > >                                           ^
> > >                                           {}
> > > 
> > > Most initializations of structs in the kernel seem to use this format.
[]
> > So { { { 0 } } } seems to be the safest option. We could go with static
> > but it looks even uglier to me.
> > 
> > Joe, suggestions?

If this is really an issue, I don't know why the other uses
haven't been reported.  Perhaps change the rest of them too?

$ git grep -P "struct\s+in6_addr\s+\w+\s*=\s*{\s*}"
include/net/ip6_fib.h:          struct in6_addr in6_zero = {};
include/trace/events/fib6.h:                    struct in6_addr in6_zero = {};
net/6lowpan/iphc.c:     struct in6_addr network_pfx = {};
net/6lowpan/iphc.c:     struct in6_addr tmp = {};
net/6lowpan/iphc.c:     struct in6_addr tmp = {};
net/6lowpan/iphc.c:     struct in6_addr tmp = {};
net/6lowpan/iphc.c:     struct in6_addr tmp = {};

Re: [PATCH net-next v2] geneve: Use empty braces for addr6 initializer

[Stefano Brivio]

On Fri, 16 Nov 2018 18:33:40 -0800
Joe Perches <joe@perches.com> wrote:

> If this is really an issue, I don't know why the other uses
> haven't been reported.

It causes warnings with some older gcc versions and clang, I don't see
it as an issue, but others might.

> Perhaps change the rest of them too?

But then look, we already have a delicious strict C89 initialiser in
include/linux/in6.h, and we can do this:

 drivers/net/geneve.c        |    4 ++--
 include/net/ip6_fib.h       |    9 +++------
 include/trace/events/fib6.h |    4 +---
 net/6lowpan/iphc.c          |   12 ++++++------
 4 files changed, 12 insertions(+), 17 deletions(-)

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index 7c53e06b31c3..96588adc294c 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -191,7 +191,7 @@ static struct geneve_dev *geneve_lookup_skb(struct geneve_sock *gs,
                return geneve_lookup(gs, addr, vni);
 #if IS_ENABLED(CONFIG_IPV6)
        } else if (geneve_get_sk_family(gs) == AF_INET6) {
-               static struct in6_addr zero_addr6;
+               struct in6_addr zero_addr6 = IN6ADDR_ANY_INIT;
                struct ipv6hdr *ip6h;
                struct in6_addr addr6;
 
@@ -424,8 +424,8 @@ static int geneve_udp_encap_err_lookup(struct sock *sk, struct sk_buff *skb)
 
 #if IS_ENABLED(CONFIG_IPV6)
        if (geneve_get_sk_family(gs) == AF_INET6) {
+               struct in6_addr addr6 = IN6ADDR_ANY_INIT;
                struct ipv6hdr *ip6h = ipv6_hdr(skb);
-               struct in6_addr addr6 = { 0 };
 
                if (!gs->collect_md) {
                        vni = geneve_hdr(skb)->vni;
diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h
index 84097010237c..24543caf5a9f 100644
--- a/include/net/ip6_fib.h
+++ b/include/net/ip6_fib.h
@@ -427,13 +427,10 @@ void rt6_get_prefsrc(const struct rt6_info *rt, struct in6_addr *addr)
        rcu_read_lock();
 
        from = rcu_dereference(rt->from);
-       if (from) {
+       if (from)
                *addr = from->fib6_prefsrc.addr;
-       } else {
-               struct in6_addr in6_zero = {};
-
-               *addr = in6_zero;
-       }
+       else
+               *addr = in6addr_any;
 
        rcu_read_unlock();
 }
diff --git a/include/trace/events/fib6.h b/include/trace/events/fib6.h
index b088b54d699c..6496ca1594ac 100644
--- a/include/trace/events/fib6.h
+++ b/include/trace/events/fib6.h
@@ -68,10 +68,8 @@ TRACE_EVENT(fib6_table_lookup,
                        __assign_str(name, "-");
                }
                if (f6i == net->ipv6.fib6_null_entry) {
-                       struct in6_addr in6_zero = {};
-
                        in6 = (struct in6_addr *)__entry->gw;
-                       *in6 = in6_zero;
+                       *in6 = in6addr_any;
 
                } else if (f6i) {
                        in6 = (struct in6_addr *)__entry->gw;
diff --git a/net/6lowpan/iphc.c b/net/6lowpan/iphc.c
index 52fad5dad9f7..f0e0bac91e71 100644
--- a/net/6lowpan/iphc.c
+++ b/net/6lowpan/iphc.c
@@ -246,8 +246,8 @@ lowpan_iphc_ctx_get_by_mcast_addr(const struct net_device *dev,
                                  const struct in6_addr *addr)
 {
        struct lowpan_iphc_ctx *table = lowpan_dev(dev)->ctx.table;
+       struct in6_addr addr_mcast, network_pfx = IN6ADDR_ANY_INIT;
        struct lowpan_iphc_ctx *ret = NULL;
-       struct in6_addr addr_mcast, network_pfx = {};
        int i;
 
        /* init mcast address with  */
@@ -481,7 +481,7 @@ static int lowpan_uncompress_multicast_ctx_daddr(struct sk_buff *skb,
                                                 struct in6_addr *ipaddr,
                                                 u8 address_mode)
 {
-       struct in6_addr network_pfx = {};
+       struct in6_addr network_pfx = IN6ADDR_ANY_INIT;
        bool fail;
 
        ipaddr->s6_addr[0] = 0xFF;
@@ -794,8 +794,8 @@ lowpan_iphc_compress_ctx_802154_lladdr(const struct in6_addr *ipaddr,
 {
        const struct ieee802154_addr *addr = lladdr;
        unsigned char extended_addr[EUI64_ADDR_LEN];
+       struct in6_addr tmp = IN6ADDR_ANY_INIT;
        bool lladdr_compress = false;
-       struct in6_addr tmp = {};
 
        switch (addr->mode) {
        case IEEE802154_ADDR_LONG:
@@ -833,7 +833,7 @@ static bool lowpan_iphc_addr_equal(const struct net_device *dev,
                                   const struct in6_addr *ipaddr,
                                   const void *lladdr)
 {
-       struct in6_addr tmp = {};
+       struct in6_addr tmp = IN6ADDR_ANY_INIT;
 
        lowpan_iphc_uncompress_lladdr(dev, &tmp, lladdr);
 
@@ -848,7 +848,7 @@ static u8 lowpan_compress_ctx_addr(u8 **hc_ptr, const struct net_device *dev,
                                   const struct lowpan_iphc_ctx *ctx,
                                   const unsigned char *lladdr, bool sam)
 {
-       struct in6_addr tmp = {};
+       struct in6_addr tmp = IN6ADDR_ANY_INIT;
        u8 dam;
 
        switch (lowpan_dev(dev)->lltype) {
@@ -907,8 +907,8 @@ lowpan_iphc_compress_802154_lladdr(const struct in6_addr *ipaddr,
 {
        const struct ieee802154_addr *addr = lladdr;
        unsigned char extended_addr[EUI64_ADDR_LEN];
+       struct in6_addr tmp = IN6ADDR_ANY_INIT;
        bool lladdr_compress = false;
-       struct in6_addr tmp = {};
 
        switch (addr->mode) {
        case IEEE802154_ADDR_LONG:

-- 
Stefano

Re: [PATCH net-next v3] geneve: Initialize addr6 with memset

[David Miller]

From: Nathan Chancellor <natechancellor@gmail.com>
Date: Fri, 16 Nov 2018 18:36:27 -0700

> Clang warns:
> 
> drivers/net/geneve.c:428:29: error: suggest braces around initialization
> of subobject [-Werror,-Wmissing-braces]
>                 struct in6_addr addr6 = { 0 };
>                                           ^
>                                           {}
> 
> Rather than trying to appease the various compilers that support the
> kernel, use memset, which is unambiguous.
> 
> Fixes: a07966447f39 ("geneve: ICMP error lookup handler")
> Suggested-by: David S. Miller <davem@davemloft.net>
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

Applied.