On 3/10/20 1:40 AM, Nathan Chancellor wrote: > On Fri, Mar 06, 2020 at 01:32:42PM +0000, Vincenzo Frascino wrote: >> Enable Clang Compilation for the vdso32 library. >> >> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> >> Cc: Will Deacon <will@xxxxxxxxxx> >> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx> >> --- >> arch/arm64/kernel/vdso32/Makefile | 13 ++++++++++++- >> 1 file changed, 12 insertions(+), 1 deletion(-) >> >> diff --git a/arch/arm64/kernel/vdso32/Makefile b/arch/arm64/kernel/vdso32/Makefile >> index 04df57b43cb1..650cfc5757eb 100644 >> --- a/arch/arm64/kernel/vdso32/Makefile >> +++ b/arch/arm64/kernel/vdso32/Makefile >> @@ -10,7 +10,18 @@ include $(srctree)/lib/vdso/Makefile >> >> # Same as cc-*option, but using CC_COMPAT instead of CC >> ifeq ($(CONFIG_CC_IS_CLANG), y) >> -CC_COMPAT ?= $(CC) >> +COMPAT_GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE_COMPAT)elfedit)) >> +COMPAT_GCC_TOOLCHAIN := $(realpath $(COMPAT_GCC_TOOLCHAIN_DIR)/..) >> + >> +CLANG_CC_COMPAT := $(CC) >> +CLANG_CC_COMPAT += --target=$(notdir $(CROSS_COMPILE_COMPAT:%-=%)) >> +CLANG_CC_COMPAT += --prefix=$(COMPAT_GCC_TOOLCHAIN_DIR) >> +CLANG_CC_COMPAT += -no-integrated-as -Qunused-arguments >> +ifneq ($(COMPAT_GCC_TOOLCHAIN),) >> +CLANG_CC_COMPAT += --gcc-toolchain=$(COMPAT_GCC_TOOLCHAIN) >> +endif >> + >> +CC_COMPAT ?= $(CLANG_CC_COMPAT) >> else >> CC_COMPAT ?= $(CROSS_COMPILE_COMPAT)gcc >> endif >> -- >> 2.25.1 >> > If CC_COMPAT is ever specified on the command line as clang (maybe by > some unsuspecting user), we'd loose all of the above flags. Maybe it > would be better to build a set of COMPAT_CLANG_FLAGS and append them to > CC_COMPAT, maybe like below? > Fine by me. > Regardless, the current approach works in my testing with clang 9.0.1 > and master (clang 11.0.0). This patch specifically is: > Good to hear. I will add your tags to the patch. > Reviewed-by: Nathan Chancellor <natechancellor@xxxxxxxxx> > Tested-by: Nathan Chancellor <natechancellor@xxxxxxxxx> # build > > ================================================================================== > > diff --git a/arch/arm64/kernel/vdso32/Makefile b/arch/arm64/kernel/vdso32/Makefile > index 650cfc5757eb..df5145fab287 100644 > --- a/arch/arm64/kernel/vdso32/Makefile > +++ b/arch/arm64/kernel/vdso32/Makefile > @@ -13,15 +13,16 @@ ifeq ($(CONFIG_CC_IS_CLANG), y) > COMPAT_GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE_COMPAT)elfedit)) > COMPAT_GCC_TOOLCHAIN := $(realpath $(COMPAT_GCC_TOOLCHAIN_DIR)/..) > > -CLANG_CC_COMPAT := $(CC) > -CLANG_CC_COMPAT += --target=$(notdir $(CROSS_COMPILE_COMPAT:%-=%)) > -CLANG_CC_COMPAT += --prefix=$(COMPAT_GCC_TOOLCHAIN_DIR) > -CLANG_CC_COMPAT += -no-integrated-as -Qunused-arguments > +COMPAT_CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE_COMPAT:%-=%)) > +COMPAT_CLANG_FLAGS += --prefix=$(COMPAT_GCC_TOOLCHAIN_DIR) > +COMPAT_CLANG_FLAGS += -no-integrated-as -Qunused-arguments > ifneq ($(COMPAT_GCC_TOOLCHAIN),) > -CLANG_CC_COMPAT += --gcc-toolchain=$(COMPAT_GCC_TOOLCHAIN) > +COMPAT_CLANG_FLAGS += --gcc-toolchain=$(COMPAT_GCC_TOOLCHAIN) > endif > > -CC_COMPAT ?= $(CLANG_CC_COMPAT) > +CC_COMPAT ?= $(CC) > +CC_COMPAT += $(COMPAT_CLANG_FLAGS) > + > else > CC_COMPAT ?= $(CROSS_COMPILE_COMPAT)gcc > endif > -- Regards, Vincenzo
