[PATCH] kbuild: drop -Wno-unknown-warning-option from clang options

[Masahiro Yamada]

Since commit c3f0d0bc5b01 ("kbuild, LLVMLinux: Add -Werror to
cc-option to support clang"), cc-option and friends work correctly
for clang.

However, the combination of -Werror and -Wno-unknown-warning-option
makes clang happy with any unknown warning options.

Once -Wno-unknown-warning-option is added, any succeeding call of
cc-disable-warning is evaluated positive, then unknown warning
options are accepted.  This should be dropped.

Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
---

 Makefile                   | 1 -
 scripts/Makefile.extrawarn | 1 -
 2 files changed, 2 deletions(-)

diff --git a/Makefile b/Makefile
index 57a3695..03a9f9b 100644
--- a/Makefile
+++ b/Makefile
@@ -696,7 +696,6 @@ KBUILD_CFLAGS += $(stackp-flag)
 
 ifeq ($(cc-name),clang)
 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
-KBUILD_CPPFLAGS += $(call cc-option,-Wno-unknown-warning-option,)
 KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable)
 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
index 7c321a6..fb3522f 100644
--- a/scripts/Makefile.extrawarn
+++ b/scripts/Makefile.extrawarn
@@ -64,7 +64,6 @@ ifeq ($(cc-name),clang)
 KBUILD_CFLAGS += $(call cc-disable-warning, initializer-overrides)
 KBUILD_CFLAGS += $(call cc-disable-warning, unused-value)
 KBUILD_CFLAGS += $(call cc-disable-warning, format)
-KBUILD_CFLAGS += $(call cc-disable-warning, unknown-warning-option)
 KBUILD_CFLAGS += $(call cc-disable-warning, sign-compare)
 KBUILD_CFLAGS += $(call cc-disable-warning, format-zero-length)
 KBUILD_CFLAGS += $(call cc-disable-warning, uninitialized)
-- 
2.7.4