From: Arnd Bergmann <arnd@arndb.de>
Date: Tue, 8 Mar 2022 22:56:12 +0100
Subject: Kbuild: add -Wno-shift-negative-value where -Wextra is used
Git-commit: 1344794a59db2bd44b4919d2d75300fd3b1c2cd7
Patch-mainline: 5.18-rc1
References: bsc#1204877
As a preparation for moving to -std=gnu11, turn off the
-Wshift-negative-value option. This warning is enabled by gcc when
building with -Wextra for c99 or higher, but not for c89. Since
the kernel already relies on well-defined overflow behavior,
the warning is not helpful and can simply be disabled in
all locations that use -Wextra.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM/Clang v13.0.0 (x86-64)
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
drivers/gpu/drm/i915/Makefile | 1 +
drivers/staging/greybus/tools/Makefile | 3 ++-
fs/btrfs/Makefile | 1 +
scripts/Makefile.extrawarn | 1 +
4 files changed, 5 insertions(+), 1 deletion(-)
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -17,6 +17,7 @@
subdir-ccflags-y += -Wno-type-limits
subdir-ccflags-y += -Wno-missing-field-initializers
subdir-ccflags-y += -Wno-sign-compare
+subdir-ccflags-y += -Wno-shift-negative-value
subdir-ccflags-y += $(call cc-disable-warning, unused-but-set-variable)
subdir-ccflags-y += $(call cc-disable-warning, frame-address)
subdir-ccflags-$(CONFIG_DRM_I915_WERROR) += -Werror
--- a/drivers/staging/greybus/tools/Makefile
+++ b/drivers/staging/greybus/tools/Makefile
@@ -12,7 +12,8 @@
-Wredundant-decls \
-Wcast-align \
-Wsign-compare \
- -Wno-missing-field-initializers
+ -Wno-missing-field-initializers \
+ -Wno-shift-negative-value
CC := $(CROSS_COMPILE)gcc
--- a/fs/btrfs/Makefile
+++ b/fs/btrfs/Makefile
@@ -17,6 +17,7 @@
subdir-ccflags-y += -Wno-missing-field-initializers
subdir-ccflags-y += -Wno-sign-compare
subdir-ccflags-y += -Wno-type-limits
+subdir-ccflags-y += -Wno-shift-negative-value
obj-$(CONFIG_BTRFS_FS) := btrfs.o
--- a/scripts/Makefile.extrawarn
+++ b/scripts/Makefile.extrawarn
@@ -36,6 +36,7 @@
KBUILD_CFLAGS += -Wno-missing-field-initializers
KBUILD_CFLAGS += -Wno-sign-compare
KBUILD_CFLAGS += -Wno-type-limits
+KBUILD_CFLAGS += -Wno-shift-negative-value
KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN1