Re: drivers/media/v4l2-core/v4l2-ioctl.c:303:28: warning: taking address of packed member 'pixelformat' of class or structure 'v4l2_pix_format_mplane' may result in an unaligned pointer value
From: Andy Shevchenko
Date: Fri Nov 05 2021 - 06:22:28 EST
On Fri, Nov 5, 2021 at 12:24 AM kernel test robot <lkp@xxxxxxxxx> wrote:
>
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: c1e2e0350ce37f633b5ce3ce1cdf4428513fc2a2
> commit: e927e1e0f0dd3e353d5556503a71484008692c82 v4l: ioctl: Use %p4cc printk modifier to print FourCC codes
> date: 9 months ago
> config: mips-randconfig-r011-20211101 (attached as .config)
> compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 82ed106567063ea269c6d5669278b733e173a42f)
> 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=e927e1e0f0dd3e353d5556503a71484008692c82
> git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> git fetch --no-tags linus master
> git checkout e927e1e0f0dd3e353d5556503a71484008692c82
> # save the attached .config to linux build tree
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=mips
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
>
> All warnings (new ones prefixed by >>):
>
> >> drivers/media/v4l2-core/v4l2-ioctl.c:303:28: warning: taking address of packed member 'pixelformat' of class or structure 'v4l2_pix_format_mplane' may result in an unaligned pointer value [-Waddress-of-packed-member]
Yeah, I discussed it with Sakari a few months ago. Dunno what is the outcome.
TL;DR: some are easy to fix, i.e. by dropping __packed, the rest needs
more thinking...
--
With Best Regards,
Andy Shevchenko