Re: [PATCH dpdk v2] mbuf: fix strict aliasing error in allocator

[Thomas Monjalon <thomas@monjalon.net>]

25/09/2024 17:47, Stephen Hemminger:
> On Wed, 25 Sep 2024 11:40:54 -0400
> Robin Jarry <rjarry@redhat.com> wrote:
> 
> > From: Robin Jarry <rjarry@redhat.com>
> > To: dev@dpdk.org
> > Subject: [PATCH dpdk v2] mbuf: fix strict aliasing error in allocator
> > Date: Wed, 25 Sep 2024 11:40:54 -0400
> > 
> > When building an application with -fstrict-aliasing -Wstrict-aliasing=2,
> > we get errors triggered by rte_mbuf_raw_alloc() which is called inline
> > from rte_pktmbuf_alloc().
> > 
> >  ../dpdk/lib/mbuf/rte_mbuf.h: In function ‘rte_mbuf_raw_alloc’:
> >  ../dpdk/lib/mbuf/rte_mbuf.h:600:42: error: dereferencing type-punned
> >  pointer might break strict-aliasing rules [-Werror=strict-aliasing]
> >    600 |         if (rte_mempool_get(mp, (void **)&m) < 0)
> >        |                                          ^~
> > 
> > Avoid incorrect casting by using an inline union variable.
> > 
> > Signed-off-by: Robin Jarry <rjarry@redhat.com>
> 
> Thanks, union is safer than cast.
> 
> Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>

Applied, thanks.