[PATCH 21.11] ring: squash gcc 12.2.1 warnings

[David Marchand]

On Tue, Dec 20, 2022 at 1:38 PM Kevin Traynor <ktraynor at redhat.com> wrote:
>
> gcc 12.2.1 on Fedora 37 is giving stringop-overread and
> stringop-overflow warnings when compiled with --buildtype=debug
> e.g. [1].
>
> These are not yet fixed on main branch. They look similar
> to the overflow issues previously squashed in rte_memcpy with
> commit b5b3ea803e47 ("eal/x86: ignore gcc 10 stringop-overflow warnings")
>
> In order to ensure DPDK 21.11.3 compiles on Fedora 37, squash these
> warnings. If a subsequent cleaner fix becomes available on from main
> branch it can be backported to later DPDK 21.11 LTS release.
>
> [1]
> lib/ring/rte_ring_elem_pvt.h:100:25: error:
> ‘memcpy’ reading 32 bytes from a region of size 4
> [-Werror=stringop-overread]
> 100 |               memcpy((void *)(ring + idx),
>     |               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 101 |                       (const void *)(obj + i), 32);
>     |                       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> lib/ring/rte_ring_elem_pvt.h:234:25: error:
> ‘memcpy’ writing 32 bytes into a region of size 4 overflows the destination
> [-Werror=stringop-overflow=]
> 234 |               memcpy((void *)(obj + i), (void *)(ring + idx), 32);
>     |               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> Signed-off-by: Kevin Traynor <ktraynor at redhat.com>

As mentionned in this thread:
https://inbox.dpdk.org/dev/ZBLqF6c3ujMic45N@bricha3-MOBL.ger.corp.intel.com/T/#me1c8f06a9ca2cf2a4ed4a028d373a3e3ce5146d1
I intend to pull this change in the main repository and mark this
change for backports in other stable branches.

I'll do this for -rc3, expected tomorrow, unless someone objects.


-- 
David Marchand