Re: [PATCH net-next v2 1/1] netfilter: conntrack: Guard possible unused functions

[Simon Horman]

On Mon, Sep 09, 2024 at 06:39:56PM +0300, Andy Shevchenko wrote:
> Some of the functions may be unused, it prevents kernel builds
> with clang, `make W=1` and CONFIG_WERROR=y:
> 
> net/netfilter/nf_conntrack_netlink.c:657:22: error: unused function 'ctnetlink_acct_size' [-Werror,-Wunused-function]
>   657 | static inline size_t ctnetlink_acct_size(const struct nf_conn *ct)
>       |                      ^~~~~~~~~~~~~~~~~~~
> net/netfilter/nf_conntrack_netlink.c:667:19: error: unused function 'ctnetlink_secctx_size' [-Werror,-Wunused-function]
>   667 | static inline int ctnetlink_secctx_size(const struct nf_conn *ct)
>       |                   ^~~~~~~~~~~~~~~~~~~~~
> net/netfilter/nf_conntrack_netlink.c:683:22: error: unused function 'ctnetlink_timestamp_size' [-Werror,-Wunused-function]
>   683 | static inline size_t ctnetlink_timestamp_size(const struct nf_conn *ct)
>       |                      ^~~~~~~~~~~~~~~~~~~~~~~~
> 
> Fix this by guarding possible unused functions with ifdeffery.

I think it would be worth mentioning, that
the condition is that neither CONFIG_NETFILTER_NETLINK_GLUE_CT
nor CONFIG_NF_CONNTRACK_EVENTS are defined (enabled).

> 
> See also commit 6863f5643dd7 ("kbuild: allow Clang to find unused static
> inline functions for W=1 build").
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> ---
> v2: fixed typo, dropped Fixes (Simon), optimised by reusing existing ifdeffery
>  net/netfilter/nf_conntrack_netlink.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

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