Re: [PATCH] event/octeontx: fix clang 6 linker error

[Jerin Jacob <jerin.jacob@caviumnetworks.com>]

-----Original Message-----
> Date: Wed,  9 May 2018 02:56:00 +0530
> From: Pavan Nikhilesh <pbhagavatula@caviumnetworks.com>
> To: jerin.jacob@caviumnetworks.com, santosh.shukla@caviumnetworks.com,
>  arybchenko@solarflare.com
> Cc: dev@dpdk.org, Pavan Nikhilesh <pbhagavatula@caviumnetworks.com>
> Subject: [dpdk-dev] [PATCH] event/octeontx: fix clang 6 linker error
> X-Mailer: git-send-email 2.17.0
> 
> Clang 6 & 7 fail to naturally align packed structs due to this clang
> can't use 8byte atomic primitives and splits them into lesser atomic
> primitives. To use lesser atomic primitives we need to link libatomic
> (-latomic), instead supply alignment attribute to the compiler.
> 
> timvf_worker.c:(.text+0x498): undefined reference to `__atomic_fetch_add_8'
> timvf_worker.c:(.text+0x525): undefined reference to `__atomic_store_2'
> timvf_worker.c:(.text+0x557): undefined reference to `__atomic_fetch_add_4'
> timvf_worker.c:(.text+0x5de): undefined reference to `__atomic_store_2'
> 
> Fixes: f874c1eb1519 ("event/octeontx: create and free timer adapter")
> 

Reported-by: Andrew Rybchenko <arybchenko@solarflare.com>

> Signed-off-by: Pavan Nikhilesh <pbhagavatula@caviumnetworks.com>

Acked-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>


> ---
>  drivers/event/octeontx/timvf_evdev.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/event/octeontx/timvf_evdev.h b/drivers/event/octeontx/timvf_evdev.h
> index b1b2a8464..1cac1e612 100644
> --- a/drivers/event/octeontx/timvf_evdev.h
> +++ b/drivers/event/octeontx/timvf_evdev.h
> @@ -145,7 +145,7 @@ struct tim_mem_bucket {
>  	};
>  	uint64_t current_chunk;
>  	uint64_t pad;
> -} __rte_packed;
> +} __rte_packed __rte_aligned(8);
> 
>  struct tim_mem_entry {
>  	uint64_t w0;
> --
> 2.17.0
>