Re: fs/ntfs3/fsntfs.c:2248:41: warning: taking address of packed member 'de' of class or structure 'NTFS_DE_SII' may result in an unaligned pointer value

[Nathan Chancellor]

On Mon, Jan 24, 2022 at 11:21:59PM +0800, kernel test robot wrote:
> Hi Konstantin,
> 
> FYI, the error/warning still remains.
> 
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head:   dd81e1c7d5fb126e5fbc5c9e334d7b3ec29a16a0
> commit: 6e5be40d32fb1907285277c02e74493ed43d77fe fs/ntfs3: Add NTFS3 in fs/Kconfig and fs/Makefile
> date:   5 months ago
> config: mips-buildonly-randconfig-r001-20220122 (https://download.01.org/0day-ci/archive/20220124/202201242326.uQ3OazUi-lkp@xxxxxxxxx/config)
> compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 7b3d30728816403d1fd73cc5082e9fb761262bce)
> 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
>         # install mips cross compiling tool for clang build
>         # apt-get install binutils-mips-linux-gnu
>         # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6e5be40d32fb1907285277c02e74493ed43d77fe
>         git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
>         git fetch --no-tags linus master
>         git checkout 6e5be40d32fb1907285277c02e74493ed43d77fe
>         # save the config file to linux build tree
>         mkdir build_dir
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=mips SHELL=/bin/bash fs/ntfs3/
> 
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> 
> All warnings (new ones prefixed by >>):
> 
>    fs/ntfs3/fsntfs.c:1874:9: warning: variable 'cnt' set but not used [-Wunused-but-set-variable]
>            size_t cnt, off;
>                   ^
> >> fs/ntfs3/fsntfs.c:2248:41: warning: taking address of packed member 'de' of class or structure 'NTFS_DE_SII' may result in an unaligned pointer value [-Waddress-of-packed-member]
>            err = indx_insert_entry(indx_sii, ni, &sii_e.de, NULL, NULL);
>                                                   ^~~~~~~~
>    2 warnings generated.

This warning has the same root cause as
https://lore.kernel.org/r/YenXz+RznXBuJMSR@dev-arch.archlinux-ax161/.

Intel folks, would it be possible to limit instances of
-Waddress-of-packed-member with mips randconfigs to our mailing list for
the reason I note in the link above?

Cheers,
Nathan