On Tue, Apr 9, 2019 at 8:48 PM Michael Chang <mch...@suse.com> wrote: > > This patch set attempts to resolve the build failure in openSUSE build > service equipped with new gcc 9 compiler, which has added a new warning > flag -Waddress-of-packed-member. > > The new warning performs the check for taking the address of packed > member directly to a pointer variable with higher alignment requirement > and the outcome is risky to memory alignment fault on some architecture > when deferencing it. The problem here is that there is no way to tell the compiler to create a structure without padding but a pointer to which is aligned. This is very common in GRUB. Consider a struct like following: grub_uint16_t a; grub_uint32_t b; grub_uint16_t c[40];
This needs packed attribute as otherwise compiler will insert a padding before b. Yet c is guaranteed to be aligned if the pointer to the structure is aligned. > > Please help to review. > > Thanks. > > Michael Chang (8): > cpio: fix gcc9 error address-of-packed-member > jfs: fix gcc9 error address-of-packed-member > hfs: fix gcc9 error address-of-packed-member > hfsplus: fix gcc9 error address-of-packed-member > acpi: fix gcc9 error address-of-packed-member > usbtest: fix gcc9 error address-of-packed-member > chainloader: fix gcc9 error address-of-packed-member > efi: fix gcc9 error address-of-packed-member > > grub-core/commands/usbtest.c | 13 ++++++++- > grub-core/fs/cpio.c | 5 ++-- > grub-core/fs/cpio_be.c | 5 ++-- > grub-core/fs/hfsplus.c | 57 > ++++++++++++++++++++++++++------------ > grub-core/fs/jfs.c | 5 ++-- > grub-core/kern/efi/efi.c | 27 ++++++++++++++++-- > grub-core/loader/efi/chainloader.c | 12 ++++++-- > include/grub/acpi.h | 2 +- > include/grub/hfs.h | 2 +- > 9 files changed, 96 insertions(+), 32 deletions(-) > > -- > 2.16.4 > > > _______________________________________________ > Grub-devel mailing list > Grub-devel@gnu.org > https://lists.gnu.org/mailman/listinfo/grub-devel -- Regards Vladimir 'phcoder' Serbinenko _______________________________________________ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
