Re: [PATCH 1/6] osdep/windows/platform: Disable gcc9 -Waddress-of-packed-member

[Vladimir 'phcoder' Serbinenko]

LGTM

On Fri, Mar 11, 2022 at 12:38 AM Daniel Kiper <daniel.kiper@oracle.com> wrote:
>
> $ ./configure --target=x86_64-w64-mingw32 --with-platform=efi 
> --host=x86_64-w64-mingw32
> $ make
>
> [...]
>
> In file included from grub-core/osdep/platform.c:4:
> grub-core/osdep/windows/platform.c: In function ‘grub_install_register_efi’:
> grub-core/osdep/windows/platform.c:382:41: error: taking address of packed 
> member of ‘struct grub_efi_file_path_device_path’ may result in an unaligned 
> pointer value [-Werror=address-of-packed-member]
>   382 |   path16_len = grub_utf8_to_utf16 (filep->path_name,
>       |                                    ~~~~~^~~~~~~~~~~
>
> Disable the -Wadress-of-packaed-member diagnostic for grub_utf8_to_utf16()
> call which contains filep->path_name reference. It seems safe because the
> structure is defined according to the UEFI spec and we hope authors did not
> make any mistake... :-)
>
> This fix is similar to the fix in the commit 8e8723a6b
> (f2fs: Disable gcc9 -Waddress-of-packed-member).
>
> Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
> ---
>  grub-core/osdep/windows/platform.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
>
> diff --git a/grub-core/osdep/windows/platform.c 
> b/grub-core/osdep/windows/platform.c
> index 253f8d101..075776d50 100644
> --- a/grub-core/osdep/windows/platform.c
> +++ b/grub-core/osdep/windows/platform.c
> @@ -379,10 +379,20 @@ grub_install_register_efi (grub_device_t 
> efidir_grub_dev,
>    filep->header.type = GRUB_EFI_MEDIA_DEVICE_PATH_TYPE;
>    filep->header.subtype = GRUB_EFI_FILE_PATH_DEVICE_PATH_SUBTYPE;
>
> +#if __GNUC__ >= 9
> +#pragma GCC diagnostic push
> +#pragma GCC diagnostic ignored "-Waddress-of-packed-member"
> +#endif
> +
>    path16_len = grub_utf8_to_utf16 (filep->path_name,
>                                    path8_len * GRUB_MAX_UTF16_PER_UTF8,
>                                    (const grub_uint8_t *) efifile_path,
>                                    path8_len, 0);
> +
> +#if __GNUC__ >= 9
> +#pragma GCC diagnostic pop
> +#endif
> +
>    filep->path_name[path16_len] = 0;
>    filep->header.length = sizeof (*filep) + (path16_len + 1) * sizeof 
> (grub_uint16_t);
>    pathptr = &filep->path_name[path16_len + 1];
> --
> 2.11.0
>
>
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> https://lists.gnu.org/mailman/listinfo/grub-devel



-- 
Regards
Vladimir 'phcoder' Serbinenko