From:   Tom Rix <trix@redhat.com>
To:     mhiramat@kernel.org, akpm@linux-foundation.org,
        ndesaulniers@google.com, masahiroy@kernel.org, paulmck@kernel.org,
        hannes@cmpxchg.org, ojeda@kernel.org, thunder.leizhen@huawei.com,
        christophe.leroy@csgroup.eu, vbabka@suse.cz
Cc:     linux-kernel@vger.kernel.org, Tom Rix <trix@redhat.com>
Subject: [PATCH] init/Kconfig: extend -Wno-array-bounds to gcc 13
Date:   Mon,  6 Mar 2023 17:09:47 -0500
Message-Id: <20230306220947.1982272-1-trix@redhat.com>
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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@redhat.com>
---
 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