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c25d01e1c4
The unpacked unions within a packed struct generates alignment warnings
on clang for 32-bit ARM:
./usr/include/linux/vbox_vmmdev_types.h:239:4: error: field u within 'struct vmmdev_hgcm_function_parameter32'
is less aligned than 'union (unnamed union at ./usr/include/linux/vbox_vmmdev_types.h:223:2)'
and is usually due to 'struct vmmdev_hgcm_function_parameter32' being packed,
which can lead to unaligned accesses [-Werror,-Wunaligned-access]
239 | } u;
| ^
./usr/include/linux/vbox_vmmdev_types.h:254:6: error: field u within
'struct vmmdev_hgcm_function_parameter64::(anonymous union)::(unnamed at ./usr/include/linux/vbox_vmmdev_types.h:249:3)'
is less aligned than 'union (unnamed union at ./usr/include/linux/vbox_vmmdev_types.h:251:4)' and is usually due to
'struct vmmdev_hgcm_function_parameter64::(anonymous union)::(unnamed at ./usr/include/linux/vbox_vmmdev_types.h:249:3)'
being packed, which can lead to unaligned accesses [-Werror,-Wunaligned-access]
With the recent changes to compile-test the UAPI headers in more cases,
these warning in combination with CONFIG_WERROR breaks the build.
Fix the warnings.
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202512140314.DzDxpIVn-lkp@intel.com/
Reported-by: Nathan Chancellor <nathan@kernel.org>
Closes: https://lore.kernel.org/linux-kbuild/20260110-uapi-test-disable-headers-arm-clang-unaligned-access-v1-1-b7b0fa541daa@kernel.org/
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/linux-kbuild/29b2e736-d462-45b7-a0a9-85f8d8a3de56@app.fastmail.com/
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Tested-by: Nicolas Schier <nsc@kernel.org>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patch.msgid.link/20260115-kbuild-alignment-vbox-v1-2-076aed1623ff@linutronix.de
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
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