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

From: Masahiro Yamada
Date: Sun Nov 11 2018 - 22:29:12 EST


On Mon, Nov 12, 2018 at 10:05 AM Michael Ellerman <mpe@xxxxxxxxxxxxxx> wrote:
>
> Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> writes:
> > 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?
>
> Joel's changes are fairly small so you may as well merge them along with
> the rest of the series, if that's OK with you and Joel.


OK, I will.


Joel,
If you send v2, I will merge it to kbuild tree.



Thanks.



--
Best Regards
Masahiro Yamada