Merge "LLVMLINUX: kbuild, LLVMLinux: Add more compiler options for clang"

HOSTCFLAGS   := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer -std=gnu89

HOSTCXXFLAGS = -O2

ifeq ($(shell $(HOSTCC) -v 2>&1 | grep -c "clang version"), 1)

HOSTCFLAGS  += -Wno-unused-value -Wno-unused-parameter \

		-Wno-missing-field-initializers

endif

# Decide whether to build built-in, modular, or both.

# Normally, just do built-in.

KBUILD_CFLAGS += $(call cc-disable-warning, duplicate-decl-specifier)

KBUILD_CFLAGS += -Wno-undefined-optimized

KBUILD_CFLAGS += -Wno-tautological-constant-out-of-range-compare

KBUILD_CFLAGS += -Wno-asm-operand-widths

KBUILD_CFLAGS += -Wno-initializer-overrides

KBUILD_CFLAGS += -fno-builtin

# Quiet clang warning: comparison of unsigned expression < 0 is always false

KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare)

# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the

# source of a reference will be _MergedGlobals and not on of the whitelisted names.

KBUILD_AFLAGS	+= $(CLANG_FLAGS)

else

KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)

# These warnings generated too much noise in a regular build.

# Use make W=1 to enable them (see scripts/Makefile.build)

KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)