On Thu, Oct 17, 2019 at 1:30 AM Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: > > On Wed, Oct 16, 2019 at 4:11 PM Kirill A. Shutemov <kirill@xxxxxxxxxxxxx> wrote: > > > > Looks like it was fixed soon after the complain: > > > > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63567 > > Ahh, so there are gcc versions which essentially do this wrong, and > I'm not seeing it because it was fixed. > > Ho humm. Considering that this was fixed in gcc five years ago, and we > already require gc-4.6, and did that two years ago, maybe we can just > raise the requirement a bit further. If the compound literal extension is now all that's keeping us from moving to gnu99, the alternative would be to change the kernel not to use compound literals. I think some other gnu99 incompatibilities were fixed by the clang patches, such as marking inline as __gnu_inline, and other problems were avoiding by making gcc-4.5 the minimum. I've tried it out now, and found that we do use compound literals in some important code, but the number of instances is small enough that we can actually rewrite them all. Just getting the defconfig (x86-64 and arm32) building with "gcc-4.9 --std=gnu89" takes changes to around 50 files, though at least one driver (i915 gpu) needs significant additional changes beyond this: Makefile | 2 +- arch/x86/boot/compressed/acpi.c | 4 +- arch/x86/entry/vsyscall/vsyscall_64.c | 2 +- arch/x86/include/asm/pgtable_types.h | 59 ++++++++++++---------- arch/x86/include/asm/processor.h | 4 +- arch/x86/include/asm/uaccess.h | 3 +- arch/x86/mm/pat_rbtree.c | 2 +- arch/x86/platform/efi/quirks.c | 9 ++-- block/partitions/efi.c | 4 +- drivers/acpi/numa.c | 2 +- drivers/firmware/efi/efi.c | 4 +- drivers/firmware/efi/libstub/fdt.c | 2 +- drivers/firmware/efi/libstub/tpm.c | 2 +- drivers/gpu/drm/msm/adreno/adreno_gpu.h | 2 +- drivers/input/mouse/elantech.c | 22 ++++---- .../broadcom/brcm80211/brcmfmac/firmware.c | 2 +- drivers/soc/tegra/pmc.c | 8 +-- fs/proc/root.c | 2 +- include/linux/capability.h | 17 ++++--- include/linux/cpumask.h | 8 +-- include/linux/efi.h | 2 +- include/linux/futex.h | 2 +- include/linux/jump_label.h | 4 +- include/linux/nodemask.h | 20 ++++---- include/linux/property.h | 10 ++-- include/linux/rbtree.h | 7 ++- include/linux/rwlock.h | 2 +- include/linux/rwlock_types.h | 4 +- include/linux/sched/signal.h | 2 +- include/linux/spinlock.h | 2 +- include/linux/spinlock_types.h | 4 +- include/linux/uidgid.h | 13 ++++- include/uapi/linux/uuid.h | 8 +-- init/init_task.c | 4 +- kernel/audit.c | 2 +- kernel/capability.c | 2 +- kernel/cred.c | 24 ++++----- kernel/events/uprobes.c | 2 +- kernel/futex.c | 2 +- kernel/power/swap.c | 2 +- kernel/trace/trace_clock.c | 2 +- kernel/umh.c | 4 +- kernel/user.c | 6 +-- mm/backing-dev.c | 2 +- mm/init-mm.c | 2 +- mm/page_alloc.c | 2 +- mm/vmalloc.c | 4 +- net/core/fib_rules.c | 4 +- net/rds/cong.c | 2 +- security/integrity/iint.c | 2 +- security/keys/process_keys.c | 2 +- 51 files changed, 169 insertions(+), 141 deletions(-)
