[PATCH] init/Kconfig: extend -Wno-array-bounds to gcc 13

From: Tom Rix
Date: Mon Mar 06 2023 - 17:11:08 EST


With gcc 13.0.1 on x86, there are several false positives like

drivers/net/ethernet/microchip/sparx5/sparx5_psfp.c:167:31:
error: array subscript 4 is above array bounds of ‘const struct sparx5_psfp_gce[4]’ [-Werror=array-bounds=]
167 | gce = &sg->gce[i];
| ~~~~~~~^~~
In file included from drivers/net/ethernet/microchip/sparx5/sparx5_psfp.c:8:
drivers/net/ethernet/microchip/sparx5/sparx5_main.h:506:32: note: while referencing ‘gce’
506 | struct sparx5_psfp_gce gce[SPX5_PSFP_GCE_CNT];
| ^~~

The code lines for the reported problem
/* For each scheduling entry */
for (i = 0; i < sg->num_entries; i++) {
gce = &sg->gce[i];

i is bounded by num_entries, which is set in sparx5_tc_flower.c
if (act->gate.num_entries >= SPX5_PSFP_GCE_CNT) {
NL_SET_ERR_MSG_MOD(extack, "Invalid number of gate entries");
return -EINVAL;
}
..
sg->num_entries = act->gate.num_entries;

So disable array-bounds as was done on gcc 11 and 12

Signed-off-by: Tom Rix <trix@xxxxxxxxxx>
---
init/Kconfig | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/init/Kconfig b/init/Kconfig
index 1fb5f313d18f..10d0a0020726 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -898,10 +898,14 @@ config GCC11_NO_ARRAY_BOUNDS
config GCC12_NO_ARRAY_BOUNDS
def_bool y

+config GCC13_NO_ARRAY_BOUNDS
+ def_bool y
+
config CC_NO_ARRAY_BOUNDS
bool
default y if CC_IS_GCC && GCC_VERSION >= 110000 && GCC_VERSION < 120000 && GCC11_NO_ARRAY_BOUNDS
default y if CC_IS_GCC && GCC_VERSION >= 120000 && GCC_VERSION < 130000 && GCC12_NO_ARRAY_BOUNDS
+ default y if CC_IS_GCC && GCC_VERSION >= 130000 && GCC_VERSION < 140000 && GCC13_NO_ARRAY_BOUNDS

#
# For architectures that know their GCC __int128 support is sound
--
2.27.0