kbuild: Disable -Wpointer-to-enum-cast

Clang's -Wpointer-to-int-cast deviates from GCC in that it warns when
casting to enums. The kernel does this in certain places, such as device
tree matches to set the version of the device being used, which allows
the kernel to avoid using a gigantic union.

https://elixir.bootlin.com/linux/v5.5.8/source/drivers/ata/ahci_brcm.c#L428
https://elixir.bootlin.com/linux/v5.5.8/source/drivers/ata/ahci_brcm.c#L402
https://elixir.bootlin.com/linux/v5.5.8/source/include/linux/mod_devicetable.h#L264

To avoid a ton of false positive warnings, disable this particular part
of the warning, which has been split off into a separate diagnostic so
that the entire warning does not need to be turned off for clang. It
will be visible under W=1 in case people want to go about fixing these
easily and enabling the warning treewide.

Cc: stable@vger.kernel.org
Link: https://github.com/ClangBuiltLinux/linux/issues/887
Link: 2a41b31fcd
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This commit is contained in:
Nathan Chancellor 2020-03-11 12:41:21 -07:00 committed by Masahiro Yamada
parent 2eebb7abef
commit 82f2bc2fcc
1 changed files with 1 additions and 0 deletions

View File

@ -48,6 +48,7 @@ KBUILD_CFLAGS += -Wno-initializer-overrides
KBUILD_CFLAGS += -Wno-format KBUILD_CFLAGS += -Wno-format
KBUILD_CFLAGS += -Wno-sign-compare KBUILD_CFLAGS += -Wno-sign-compare
KBUILD_CFLAGS += -Wno-format-zero-length KBUILD_CFLAGS += -Wno-format-zero-length
KBUILD_CFLAGS += $(call cc-disable-warning, pointer-to-enum-cast)
endif endif
endif endif