mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Zhouyi Zhou <zhouzhouyi@gmail.com>
To: akpm@linux-foundation.org, pmladek@suse.com,
	masahiroy@kernel.org, yoann.congal@smile.fr,
	rdunlap@infradead.org, gustavoars@kernel.org, nphamcs@gmail.com,
	vincent.guittot@linaro.org, linux-kernel@vger.kernel.org,
	rcu@vger.kernel.org
Cc: Zhouyi Zhou <zhouzhouyi@gmail.com>
Subject: [PATCH] init/Kconfig: lower to GCC version 9 check for -Warray-bounds
Date: Sat,  8 Jun 2024 01:40:27 +0000	[thread overview]
Message-ID: <20240608014027.1118686-1-zhouzhouyi@gmail.com> (raw)

commit 3e00f5802fab ("init/Kconfig: lower GCC version check for -Warray-bounds")
lowers GCC version check for -Warray-bounds, but I continue to see false positives
from -Warray-bounds in GCC 9.4.

This happens after
commit b44759705f7d ("bitmap: make bitmap_{get,set}_value8() use bitmap_{read,write}()")

During the rcuturture test in Ubuntu 20.04 GCC 9.4.0 x86_64, the compiling of
drivers/gpio/gpio-pca953x.c issues following warning:

```
  CC      drivers/gpio/gpio-pca953x.o
In file included from drivers/gpio/gpio-pca953x.c:12:
drivers/gpio/gpio-pca953x.c: In function ‘pca953x_probe’:
./include/linux/bitmap.h:799:17: error: array subscript [1, 1024] is outside array bounds of ‘long unsigned int[1]’ [-Werror=array-bounds]
  799 |  map[index + 1] &= BITMAP_FIRST_WORD_MASK(start + nbits);
      |                 ^~
In file included from ./include/linux/atomic.h:5,
                 from drivers/gpio/gpio-pca953x.c:11:
drivers/gpio/gpio-pca953x.c:1015:17: note: while referencing ‘val’
 1015 |  DECLARE_BITMAP(val, MAX_LINE);
      |                 ^~~
./include/linux/types.h:11:16: note: in definition of macro ‘DECLARE_BITMAP’
   11 |  unsigned long name[BITS_TO_LONGS(bits)]
      |                ^~~~
In file included from drivers/gpio/gpio-pca953x.c:12:
./include/linux/bitmap.h:800:17: error: array subscript [1, 1024] is outside array bounds of ‘long unsigned int[1]’ [-Werror=array-bounds]
  800 |  map[index + 1] |= (value >> space);
      |  ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~
In file included from ./include/linux/atomic.h:5,
                 from drivers/gpio/gpio-pca953x.c:11:
drivers/gpio/gpio-pca953x.c:1015:17: note: while referencing ‘val’
 1015 |  DECLARE_BITMAP(val, MAX_LINE);
      |                 ^~~
./include/linux/types.h:11:16: note: in definition of macro ‘DECLARE_BITMAP’
   11 |  unsigned long name[BITS_TO_LONGS(bits)]
```   

Disable gcc-9+ array-bounds avoid above warning.

Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
---
 init/Kconfig | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/init/Kconfig b/init/Kconfig
index 72404c1f2157..27ce2ded95b6 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -876,14 +876,14 @@ config CC_IMPLICIT_FALLTHROUGH
 	default "-Wimplicit-fallthrough=5" if CC_IS_GCC && $(cc-option,-Wimplicit-fallthrough=5)
 	default "-Wimplicit-fallthrough" if CC_IS_CLANG && $(cc-option,-Wunreachable-code-fallthrough)
 
-# Currently, disable gcc-10+ array-bounds globally.
+# Currently, disable gcc-9+ array-bounds globally.
 # It's still broken in gcc-13, so no upper bound yet.
-config GCC10_NO_ARRAY_BOUNDS
+config GCC9_NO_ARRAY_BOUNDS
 	def_bool y
 
 config CC_NO_ARRAY_BOUNDS
 	bool
-	default y if CC_IS_GCC && GCC_VERSION >= 100000 && GCC10_NO_ARRAY_BOUNDS
+	default y if CC_IS_GCC && GCC_VERSION >= 90000 && GCC9_NO_ARRAY_BOUNDS
 
 # Currently, disable -Wstringop-overflow for GCC globally.
 config GCC_NO_STRINGOP_OVERFLOW
-- 
2.25.1


             reply	other threads:[~2024-06-08  1:40 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-06-08  1:40 Zhouyi Zhou [this message]
2024-06-09  0:31 ` Zhouyi Zhou

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20240608014027.1118686-1-zhouzhouyi@gmail.com \
    --to=zhouzhouyi@gmail.com \
    --cc=akpm@linux-foundation.org \
    --cc=gustavoars@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=masahiroy@kernel.org \
    --cc=nphamcs@gmail.com \
    --cc=pmladek@suse.com \
    --cc=rcu@vger.kernel.org \
    --cc=rdunlap@infradead.org \
    --cc=vincent.guittot@linaro.org \
    --cc=yoann.congal@smile.fr \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®