[dpdk-dev] [PATCH v3 3/4] net/ice/base: fix build with gcc11

[Ferruh Yigit <ferruh.yigit@intel.com>]

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.

Since the allocation is done explicitly and both producer and consumer
are internal, safe to ignore the warnings. Also to prevent any side
affect disabling the compiler warning for now, until proper fix done.

Reducing the warning disable to gcc >= 11 version.

Bugzilla ID: 678
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>

v2:
* Kevin reported more occurrences, the concern is to have more as the
  gcc version updated. And as the size of changes increases, the risk of
  unexpected side affect also increases.
  So disabling the 'array-bounds' warning for this release for
  gcc >= 11.0.0.
---
 drivers/net/ice/base/meson.build | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/ice/base/meson.build b/drivers/net/ice/base/meson.build
index 6c548a99775c..3305e5dd1822 100644
--- a/drivers/net/ice/base/meson.build
+++ b/drivers/net/ice/base/meson.build
@@ -23,6 +23,11 @@ error_cflags = [
         '-Wno-unused-parameter',
 ]
 
+# Bugzilla ID: 678
+if (toolchain == 'gcc' and cc.version().version_compare('>=11.0.0'))
+    error_cflags += ['-Wno-array-bounds']
+endif
+
 if is_windows and cc.get_id() != 'clang'
     cflags += ['-fno-asynchronous-unwind-tables']
 endif
-- 
2.31.1