For older versions of gcc, the array = {0}; will cause warnings:
drivers/net/ethernet/mscc/ocelot_vcap.c: In function 'is1_entry_set':
drivers/net/ethernet/mscc/ocelot_vcap.c:755:11: warning: missing braces around initializer [-Wmissing-braces]
struct ocelot_vcap_u16 etype = {0};
^
drivers/net/ethernet/mscc/ocelot_vcap.c:755:11: warning: (near initialization for 'etype.value') [-Wmissing-braces]
1 warnings generated
Fixes: 75944fda1dfe ("net: mscc: ocelot: offload ingress skbedit and vlan actions to VCAP IS1")
Signed-off-by: Pujin Shi <[email protected]>
---
drivers/net/ethernet/mscc/ocelot_vcap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/mscc/ocelot_vcap.c b/drivers/net/ethernet/mscc/ocelot_vcap.c
index d8c778ee6f1b..b96eab4583e7 100644
--- a/drivers/net/ethernet/mscc/ocelot_vcap.c
+++ b/drivers/net/ethernet/mscc/ocelot_vcap.c
@@ -752,7 +752,7 @@ static void is1_entry_set(struct ocelot *ocelot, int ix,
dport);
} else {
/* IPv4 "other" frame */
- struct ocelot_vcap_u16 etype = {0};
+ struct ocelot_vcap_u16 etype = {};
/* Overloaded field */
etype.value[0] = proto.value[0];
--
2.18.1
On Mon, Nov 02, 2020 at 09:41:36PM +0800, Pujin Shi wrote:
> For older versions of gcc, the array = {0}; will cause warnings:
>
> drivers/net/ethernet/mscc/ocelot_vcap.c: In function 'is1_entry_set':
> drivers/net/ethernet/mscc/ocelot_vcap.c:755:11: warning: missing braces around initializer [-Wmissing-braces]
> struct ocelot_vcap_u16 etype = {0};
> ^
> drivers/net/ethernet/mscc/ocelot_vcap.c:755:11: warning: (near initialization for 'etype.value') [-Wmissing-braces]
>
> 1 warnings generated
>
> Fixes: 75944fda1dfe ("net: mscc: ocelot: offload ingress skbedit and vlan actions to VCAP IS1")
> Signed-off-by: Pujin Shi <[email protected]>
> ---
> drivers/net/ethernet/mscc/ocelot_vcap.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/mscc/ocelot_vcap.c b/drivers/net/ethernet/mscc/ocelot_vcap.c
> index d8c778ee6f1b..b96eab4583e7 100644
> --- a/drivers/net/ethernet/mscc/ocelot_vcap.c
> +++ b/drivers/net/ethernet/mscc/ocelot_vcap.c
> @@ -752,7 +752,7 @@ static void is1_entry_set(struct ocelot *ocelot, int ix,
> dport);
> } else {
> /* IPv4 "other" frame */
> - struct ocelot_vcap_u16 etype = {0};
> + struct ocelot_vcap_u16 etype = {};
>
> /* Overloaded field */
> etype.value[0] = proto.value[0];
> --
> 2.18.1
>
Sorry, I don't understand what the problem is, or why your patch fixes
it. What version of gcc are you testing with?
On Mon, Nov 02, 2020 at 01:56:55PM +0000, Vladimir Oltean wrote:
> On Mon, Nov 02, 2020 at 09:41:36PM +0800, Pujin Shi wrote:
> > For older versions of gcc, the array = {0}; will cause warnings:
> >
> > drivers/net/ethernet/mscc/ocelot_vcap.c: In function 'is1_entry_set':
> > drivers/net/ethernet/mscc/ocelot_vcap.c:755:11: warning: missing braces around initializer [-Wmissing-braces]
> > struct ocelot_vcap_u16 etype = {0};
> > ^
> > drivers/net/ethernet/mscc/ocelot_vcap.c:755:11: warning: (near initialization for 'etype.value') [-Wmissing-braces]
> >
> > 1 warnings generated
> >
> > Fixes: 75944fda1dfe ("net: mscc: ocelot: offload ingress skbedit and vlan actions to VCAP IS1")
> > Signed-off-by: Pujin Shi <[email protected]>
> > ---
> > drivers/net/ethernet/mscc/ocelot_vcap.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/ethernet/mscc/ocelot_vcap.c b/drivers/net/ethernet/mscc/ocelot_vcap.c
> > index d8c778ee6f1b..b96eab4583e7 100644
> > --- a/drivers/net/ethernet/mscc/ocelot_vcap.c
> > +++ b/drivers/net/ethernet/mscc/ocelot_vcap.c
> > @@ -752,7 +752,7 @@ static void is1_entry_set(struct ocelot *ocelot, int ix,
> > dport);
> > } else {
> > /* IPv4 "other" frame */
> > - struct ocelot_vcap_u16 etype = {0};
> > + struct ocelot_vcap_u16 etype = {};
> >
> > /* Overloaded field */
> > etype.value[0] = proto.value[0];
>
> Sorry, I don't understand what the problem is, or why your patch fixes
> it. What version of gcc are you testing with?
Nothing wrong and { 0 } is the right initializer, the reports must be
from some ancient gcc but we weren't told which one either.
https://lore.kernel.org/linux-btrfs/[email protected]/
On Mon, 2 Nov 2020 13:56:55 +0000 Vladimir Oltean wrote:
> On Mon, Nov 02, 2020 at 09:41:36PM +0800, Pujin Shi wrote:
> > For older versions of gcc, the array = {0}; will cause warnings:
> >
> > drivers/net/ethernet/mscc/ocelot_vcap.c: In function 'is1_entry_set':
> > drivers/net/ethernet/mscc/ocelot_vcap.c:755:11: warning: missing braces around initializer [-Wmissing-braces]
> > struct ocelot_vcap_u16 etype = {0};
> > ^
> > drivers/net/ethernet/mscc/ocelot_vcap.c:755:11: warning: (near initialization for 'etype.value') [-Wmissing-braces]
> >
> > 1 warnings generated
> >
> > Fixes: 75944fda1dfe ("net: mscc: ocelot: offload ingress skbedit and vlan actions to VCAP IS1")
> > Signed-off-by: Pujin Shi <[email protected]>
> > ---
> > drivers/net/ethernet/mscc/ocelot_vcap.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/ethernet/mscc/ocelot_vcap.c b/drivers/net/ethernet/mscc/ocelot_vcap.c
> > index d8c778ee6f1b..b96eab4583e7 100644
> > --- a/drivers/net/ethernet/mscc/ocelot_vcap.c
> > +++ b/drivers/net/ethernet/mscc/ocelot_vcap.c
> > @@ -752,7 +752,7 @@ static void is1_entry_set(struct ocelot *ocelot, int ix,
> > dport);
> > } else {
> > /* IPv4 "other" frame */
> > - struct ocelot_vcap_u16 etype = {0};
> > + struct ocelot_vcap_u16 etype = {};
> >
>
> Sorry, I don't understand what the problem is, or why your patch fixes
> it. What version of gcc are you testing with?
Old GCC does not like the 0, if the members of struct are not scalars.
struct ocelot_vcap_u16 {
u8 value[2];
u8 mask[2];
};
In this case the first member is an array.
It wants us to add another curly brace:
struct ocelot_vcap_u16 etype = {{0}};
... or we can just skip the 0.
That's just FWIW. I don't remember which versions of GCC behave like
that, I just know we get a constant stream of this sort of fixes.
I think clang may generate a similar warning.
Pujin, please specify the version of GCC you're using and repost.
On Mon, Nov 02, 2020 at 02:08:08PM -0800, Jakub Kicinski wrote:
> Old GCC does not like the 0, if the members of struct are not scalars.
>
> struct ocelot_vcap_u16 {
> u8 value[2];
> u8 mask[2];
> };
>
> In this case the first member is an array.
>
> It wants us to add another curly brace:
>
> struct ocelot_vcap_u16 etype = {{0}};
>
> ... or we can just skip the 0.
I am reading that the empty set initializer is a GNU extension. I would
not like to see yet another patch from clang folks coming as a follow-up
to this one.
> That's just FWIW. I don't remember which versions of GCC behave like
> that, I just know we get a constant stream of this sort of fixes.
> I think clang may generate a similar warning.
>
> Pujin, please specify the version of GCC you're using and repost.
If the initializer really has to be changed, I would prefer to see a memset.