linux/init
Linus Torvalds f0be87c42c gcc-12: disable '-Warray-bounds' universally for now
In commit 8b202ee218 ("s390: disable -Warray-bounds") the s390 people
disabled the '-Warray-bounds' warning for gcc-12, because the new logic
in gcc would cause warnings for their use of the S390_lowcore macro,
which accesses absolute pointers.

It turns out gcc-12 has many other issues in this area, so this takes
that s390 warning disable logic, and turns it into a kernel build config
entry instead.

Part of the intent is that we can make this all much more targeted, and
use this conflig flag to disable it in only particular configurations
that cause problems, with the s390 case as an example:

        select GCC12_NO_ARRAY_BOUNDS

and we could do that for other configuration cases that cause issues.

Or we could possibly use the CONFIG_CC_NO_ARRAY_BOUNDS thing in a more
targeted way, and disable the warning only for particular uses: again
the s390 case as an example:

  KBUILD_CFLAGS_DECOMPRESSOR += $(if $(CONFIG_CC_NO_ARRAY_BOUNDS),-Wno-array-bounds)

but this ends up just doing it globally in the top-level Makefile, since
the current issues are spread fairly widely all over:

  KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds

We'll try to limit this later, since the gcc-12 problems are rare enough
that *much* of the kernel can be built with it without disabling this
warning.

Cc: Kees Cook <keescook@chromium.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-06-09 10:11:12 -07:00
..
calibrate.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
do_mounts_initrd.c kernel/do_mount_initrd: move real_root_dev sysctls to its own file 2022-04-06 13:43:44 -07:00
do_mounts_rd.c init: add an init_unlink helper 2020-07-31 08:17:52 +02:00
do_mounts.c block: remove genhd.h 2022-02-02 07:49:59 -07:00
do_mounts.h init: add an init_mknod helper 2020-07-31 08:17:54 +02:00
init_task.c kcsan: Remove redundant zero-initialization of globals 2021-12-09 16:42:26 -08:00
initramfs.c This set of changes updates init and user mode helper tasks to be 2022-06-03 16:03:05 -07:00
Kconfig gcc-12: disable '-Warray-bounds' universally for now 2022-06-09 10:11:12 -07:00
main.c This set of changes updates init and user mode helper tasks to be 2022-06-03 16:03:05 -07:00
Makefile sched/preempt: Tell about PREEMPT_DYNAMIC on kernel headers 2022-03-11 15:36:35 +01:00
noinitramfs.c init: move usermodehelper_enable() to populate_rootfs() 2021-09-08 11:50:27 -07:00
version.c kbuild: add an elfnote for whether vmlinux is built with lto 2021-04-25 05:25:42 +09:00