Re: [PATCH v2 2/2] kbuild: consolidate Clang compiler flags

From: Masahiro Yamada
Date: Sun Nov 11 2018 - 09:04:27 EST


On Sat, Nov 10, 2018 at 3:35 AM Greg Hackmann <ghackmann@xxxxxxxxxx> wrote:
>
> On 11/09/2018 10:29 AM, Nick Desaulniers wrote:
> > On Mon, Nov 5, 2018 at 7:05 PM Masahiro Yamada
> > <yamada.masahiro@xxxxxxxxxxxxx> wrote:
> >>
> >> Collect basic Clang options such as --target, --prefix, --gcc-toolchain,
> >> -no-integrated-as into a single variable CLANG_FLAGS so that it can be
> >> easily reused in other parts of Makefile.
> >>
> >> Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
> >> ---
> >>
> >> Changes in v2:
> >> - Use := flavor instead of = because $(CLANG_FLAGS) is expanded soon anyway
> >>
> >> Makefile | 13 ++++++-------
> >> 1 file changed, 6 insertions(+), 7 deletions(-)
> >>
> >> diff --git a/Makefile b/Makefile
> >> index da11700..e173a73 100644
> >> --- a/Makefile
> >> +++ b/Makefile
> >> @@ -487,18 +487,17 @@ endif
> >>
> >> ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
> >> ifneq ($(CROSS_COMPILE),)
> >> -CLANG_TARGET := --target=$(notdir $(CROSS_COMPILE:%-=%))
> >> +CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE:%-=%))
> >> GCC_TOOLCHAIN_DIR := $(dir $(shell which $(LD)))
> >> -CLANG_PREFIX := --prefix=$(GCC_TOOLCHAIN_DIR)
> >> +CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)
> >> GCC_TOOLCHAIN := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
> >> endif
> >> ifneq ($(GCC_TOOLCHAIN),)
> >> -CLANG_GCC_TC := --gcc-toolchain=$(GCC_TOOLCHAIN)
> >> +CLANG_FLAGS += --gcc-toolchain=$(GCC_TOOLCHAIN)
> >> endif
> >> -KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) $(CLANG_PREFIX)
> >> -KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) $(CLANG_PREFIX)
> >> -KBUILD_CFLAGS += -no-integrated-as
> >> -KBUILD_AFLAGS += -no-integrated-as
> >> +CLANG_FLAGS += -no-integrated-as
> >> +KBUILD_CFLAGS += $(CLANG_FLAGS)
> >> +KBUILD_AFLAGS += $(CLANG_FLAGS)
> >> endif
> >>
> >> RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
> >> --
> >> 2.7.4
> >>
> >
> > Thanks for this patch, Masahiro, it's a good simplification.
> > Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
> > Tested-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
> >
> > Would you mind waiting for a tested-by from Stefan, and maybe an ack
> > from Greg (added to cc)?
> >
>
> Acked-by: Greg Hackmann <ghackmann@xxxxxxxxxx>


Thanks for your review!


So, how to organize this series, and Joel's one together?

I'd like Joel to use this series as a base for his work.
(https://lore.kernel.org/patchwork/patch/1006696/)

It will be much cleaner.


Shall I merge all the patches to kbuild tree, or
maybe will they go through powerpc tree?




--
Best Regards
Masahiro Yamada