Re: [dpdk-dev] [PATCH 3/4] net/ice/base: fix build with gcc11

["Wang, Haiyue" <haiyue.wang@intel.com>]

> -----Original Message-----
> From: Wang, Haiyue
> Sent: Tuesday, May 11, 2021 01:05
> To: Ferruh Yigit <ferruh.yigit@intel.com>; Yang, Qiming <qiming.yang@intel.com>; Zhang, Qi Z
> <qi.z.zhang@intel.com>; Stillwell Jr, Paul M <paul.m.stillwell.jr@intel.com>; Lu, Wenzhuo
> <wenzhuo.lu@intel.com>; Rong, Leyi <leyi.rong@intel.com>; Shukla, Shivanshu
> <Shivanshu.Shukla@intel.com>
> Cc: Yigit, Ferruh <ferruh.yigit@intel.com>; dev@dpdk.org; stable@dpdk.org; Kevin Traynor
> <ktraynor@redhat.com>; Ajit Khaparde <ajit.khaparde@broadcom.com>
> Subject: RE: [dpdk-dev] [PATCH 3/4] net/ice/base: fix build with gcc11
>
> > -----Original Message-----
> > From: dev <dev-bounces@dpdk.org> On Behalf Of Ferruh Yigit
> > Sent: Monday, May 10, 2021 23:03
> > To: Yang, Qiming <qiming.yang@intel.com>; Zhang, Qi Z <qi.z.zhang@intel.com>; Stillwell Jr, Paul M
> > <paul.m.stillwell.jr@intel.com>; Lu, Wenzhuo <wenzhuo.lu@intel.com>; Rong, Leyi
> <leyi.rong@intel.com>;
> > Shukla, Shivanshu <shivanshu.shukla@intel.com>
> > Cc: Yigit, Ferruh <ferruh.yigit@intel.com>; dev@dpdk.org; stable@dpdk.org; Kevin Traynor
> > <ktraynor@redhat.com>; Ajit Khaparde <ajit.khaparde@broadcom.com>
> > Subject: [dpdk-dev] [PATCH 3/4] net/ice/base: fix build with gcc11
> >
> > Reproduced with '--buildtype=debugoptimized' config,
> > compiler version: gcc (GCC) 12.0.0 20210509 (experimental)
> >
> > There are multiple build errors, like:
> > ../drivers/net/ice/base/ice_switch.c: In function ‘ice_add_marker_act’:
> > ../drivers/net/ice/base/ice_switch.c:3727:15:
> >     warning: array subscript ‘struct ice_aqc_sw_rules_elem[0]’
> >     is partly outside array bounds of ‘unsigned char[52]’
> >     [-Warray-bounds]
> >  3727 |         lg_act->type = CPU_TO_LE16(ICE_AQC_SW_RULES_T_LG_ACT);
> >       |               ^~
> > In file included from ../drivers/net/ice/base/ice_type.h:52,
> >                  from ../drivers/net/ice/base/ice_common.h:8,
> >                  from ../drivers/net/ice/base/ice_switch.h:8,
> >                  from ../drivers/net/ice/base/ice_switch.c:5:
> > ../drivers/net/ice/base/ice_osdep.h:209:29:
> >     note: referencing an object of size 52 allocated by ‘rte_zmalloc’
> >   209 | #define ice_malloc(h, s)    rte_zmalloc(NULL, s, 0)
> >       |                             ^~~~~~~~~~~~~~~~~~~~~~~
> > ../drivers/net/ice/base/ice_switch.c:3720:50:
> >     note: in expansion of macro ‘ice_malloc’
> >   lg_act = (struct ice_aqc_sw_rules_elem *)ice_malloc(hw, rules_size);
> >
> > These errors are mainly because allocated memory is cast to
> > "struct ice_aqc_sw_rules_elem *" but allocated size is less than the size
> > of "struct ice_aqc_sw_rules_elem".
> >
> > "struct ice_aqc_sw_rules_elem" has multiple other structs has unions,
> > based on which one is used allocated memory being less than the size of
> > "struct ice_aqc_sw_rules_elem" is logically correct but compiler is
> > complaining about it.
> >
> > As a solution making sure allocated memory size is at least size of
> > "struct ice_aqc_sw_rules_elem".
> > The function to use the struct is 'ice_aq_sw_rules()', and it already has
> > parameter for size of the rule, allocating more than needed shouldn't
> > cause any problem.
> >
> > Fixes: c7dd15931183 ("net/ice/base: add virtual switch code")
> > Fixes: 02acdce2f553 ("net/ice/base: add MAC filter with marker and counter")
> > Fixes: f89aa3affa9e ("net/ice/base: support removing advanced rule")
> > Cc: stable@dpdk.org
> >
> > Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
> > ---
> > Cc: paul.m.stillwell.jr@intel.com
> > Cc: qi.z.zhang@intel.com
> > Cc: leyi.rong@intel.com
> > Cc: Kevin Traynor <ktraynor@redhat.com>
> > Cc: Ajit Khaparde <ajit.khaparde@broadcom.com>
> > ---
> >  drivers/net/ice/base/ice_switch.c | 30 +++++++++++++++++++++++-------
> >  1 file changed, 23 insertions(+), 7 deletions(-)
>
> GCC bug ?
>
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98266
>
> Bug 98266 - [11 Regression] bogus array subscript is partly outside array bounds on virtual
> inheritance
>

Disable this gcc warning ?  ;-)

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=44720996e2d79e47d508b0abe99b931a726a3197

gcc-10: disable 'array-bounds' warning for now

>
>
> > --
> > 2.31.1