include/acpi/actypes.h:525:42: warning: 'strncpy' specified bound 4 equals destination size

From: kernel test robot
Date: Wed Feb 22 2023 - 15:33:37 EST


Hi Mark,

FYI, the error/warning still remains.

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 70756b49be4ea8bf36a664322df6e7e89895fa60
commit: 8f9e0a52810dd83406c768972d022c37e7a18f1f ACPI: Don't build ACPICA with '-Os'
date: 4 weeks ago
config: ia64-defconfig (https://download.01.org/0day-ci/archive/20230223/202302230414.sQbDHtiC-lkp@xxxxxxxxx/config)
compiler: ia64-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=8f9e0a52810dd83406c768972d022c37e7a18f1f
git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
git fetch --no-tags linus master
git checkout 8f9e0a52810dd83406c768972d022c37e7a18f1f
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=ia64 olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=ia64 SHELL=/bin/bash drivers/acpi/acpica/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Link: https://lore.kernel.org/oe-kbuild-all/202302230414.sQbDHtiC-lkp@xxxxxxxxx/

All warnings (new ones prefixed by >>):

In file included from include/acpi/acpi.h:24,
from drivers/acpi/acpica/tbfind.c:10:
drivers/acpi/acpica/tbfind.c: In function 'acpi_tb_find_table':
>> include/acpi/actypes.h:525:42: warning: 'strncpy' specified bound 4 equals destination size [-Wstringop-truncation]
525 | #define ACPI_COPY_NAMESEG(dest,src) (strncpy (ACPI_CAST_PTR (char, (dest)), ACPI_CAST_PTR (char, (src)), ACPI_NAMESEG_SIZE))
| ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/acpi/acpica/tbfind.c:59:9: note: in expansion of macro 'ACPI_COPY_NAMESEG'
59 | ACPI_COPY_NAMESEG(header.signature, signature);
| ^~~~~~~~~~~~~~~~~
--
In file included from include/acpi/acpi.h:24,
from drivers/acpi/acpica/utstring.c:8:
drivers/acpi/acpica/utstring.c: In function 'acpi_ut_repair_name':
>> include/acpi/actypes.h:525:42: warning: 'strncpy' specified bound 4 equals destination size [-Wstringop-truncation]
525 | #define ACPI_COPY_NAMESEG(dest,src) (strncpy (ACPI_CAST_PTR (char, (dest)), ACPI_CAST_PTR (char, (src)), ACPI_NAMESEG_SIZE))
| ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/acpi/acpica/utstring.c:148:9: note: in expansion of macro 'ACPI_COPY_NAMESEG'
148 | ACPI_COPY_NAMESEG(&original_name, &name[0]);
| ^~~~~~~~~~~~~~~~~


vim +/strncpy +525 include/acpi/actypes.h

ff60027174cf94 Bob Moore 2012-10-31 519
50df4d8b0f6e19 Bob Moore 2008-12-31 520 #ifndef ACPI_MISALIGNMENT_NOT_SUPPORTED
5599fb69355d7a Bob Moore 2019-04-08 521 #define ACPI_COMPARE_NAMESEG(a,b) (*ACPI_CAST_PTR (u32, (a)) == *ACPI_CAST_PTR (u32, (b)))
a3ce7a8e0dd9ba Bob Moore 2019-04-08 522 #define ACPI_COPY_NAMESEG(dest,src) (*ACPI_CAST_PTR (u32, (dest)) = *ACPI_CAST_PTR (u32, (src)))
50df4d8b0f6e19 Bob Moore 2008-12-31 523 #else
3278675567dfb9 Bob Moore 2019-04-08 524 #define ACPI_COMPARE_NAMESEG(a,b) (!strncmp (ACPI_CAST_PTR (char, (a)), ACPI_CAST_PTR (char, (b)), ACPI_NAMESEG_SIZE))
3278675567dfb9 Bob Moore 2019-04-08 @525 #define ACPI_COPY_NAMESEG(dest,src) (strncpy (ACPI_CAST_PTR (char, (dest)), ACPI_CAST_PTR (char, (src)), ACPI_NAMESEG_SIZE))
50df4d8b0f6e19 Bob Moore 2008-12-31 526 #endif
50df4d8b0f6e19 Bob Moore 2008-12-31 527

:::::: The code at line 525 was first introduced by commit
:::::: 3278675567dfb901d831d46849c386a4f932905e ACPICA: Rename nameseg length macro/define for clarity

:::::: TO: Bob Moore <robert.moore@xxxxxxxxx>
:::::: CC: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests