[PATCH v2 1/2] kbuild: add -no-integrated-as Clang option unconditionally

[PATCH v2 1/2] kbuild: add -no-integrated-as Clang option unconditionally

[Masahiro Yamada]

We are still a way off the Clang's integrated assembler support for
the kernel. Hence, -no-integrated-as is mandatory to build the kernel
with Clang. If you had an ancient version of Clang that does not
recognize this option, you would not be able to compile the kernel
anyway.

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

Changes in v2:
  - New patch

 Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index 93315eb..da11700 100644
--- a/Makefile
+++ b/Makefile
@@ -497,8 +497,8 @@ CLANG_GCC_TC	:= --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 += $(call cc-option, -no-integrated-as)
-KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
+KBUILD_CFLAGS += -no-integrated-as
+KBUILD_AFLAGS += -no-integrated-as
 endif
 
 RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
-- 
2.7.4

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

[Masahiro Yamada]

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@socionext.com>
---

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

Re: [PATCH v2 1/2] kbuild: add -no-integrated-as Clang option unconditionally

[Nick Desaulniers]

On Mon, Nov 5, 2018 at 7:05 PM Masahiro Yamada
<yamada.masahiro@socionext.com> wrote:
>
> We are still a way off the Clang's integrated assembler support for
> the kernel. Hence, -no-integrated-as is mandatory to build the kernel
> with Clang. If you had an ancient version of Clang that does not
> recognize this option, you would not be able to compile the kernel
> anyway.
>
> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
> ---
>
> Changes in v2:
>   - New patch
>
>  Makefile | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/Makefile b/Makefile
> index 93315eb..da11700 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -497,8 +497,8 @@ CLANG_GCC_TC        := --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 += $(call cc-option, -no-integrated-as)
> -KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
> +KBUILD_CFLAGS += -no-integrated-as
> +KBUILD_AFLAGS += -no-integrated-as

Sorry for the delay in review.
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>

>  endif
>
>  RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
> --
> 2.7.4
>


-- 
Thanks,
~Nick Desaulniers

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

[Nick Desaulniers]

On Mon, Nov 5, 2018 at 7:05 PM Masahiro Yamada
<yamada.masahiro@socionext.com> 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@socionext.com>
> ---
>
> 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@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>

Would you mind waiting for a tested-by from Stefan, and maybe an ack
from Greg (added to cc)?
-- 
Thanks,
~Nick Desaulniers

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

[Greg Hackmann]

On 11/09/2018 10:29 AM, Nick Desaulniers wrote:
> On Mon, Nov 5, 2018 at 7:05 PM Masahiro Yamada
> <yamada.masahiro@socionext.com> 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@socionext.com>
>> ---
>>
>> 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@google.com>
> Tested-by: Nick Desaulniers <ndesaulniers@google.com>
> 
> Would you mind waiting for a tested-by from Stefan, and maybe an ack
> from Greg (added to cc)?
> 

Acked-by: Greg Hackmann <ghackmann@google.com>

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

[Masahiro Yamada]

On Sat, Nov 10, 2018 at 3:35 AM Greg Hackmann <ghackmann@google.com> wrote:
>
> On 11/09/2018 10:29 AM, Nick Desaulniers wrote:
> > On Mon, Nov 5, 2018 at 7:05 PM Masahiro Yamada
> > <yamada.masahiro@socionext.com> 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@socionext.com>
> >> ---
> >>
> >> 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@google.com>
> > Tested-by: Nick Desaulniers <ndesaulniers@google.com>
> >
> > Would you mind waiting for a tested-by from Stefan, and maybe an ack
> > from Greg (added to cc)?
> >
>
> Acked-by: Greg Hackmann <ghackmann@google.com>


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

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

[Michael Ellerman]

Masahiro Yamada <yamada.masahiro@socionext.com> writes:
> On Sat, Nov 10, 2018 at 3:35 AM Greg Hackmann <ghackmann@google.com> wrote:
>>
>> On 11/09/2018 10:29 AM, Nick Desaulniers wrote:
>> > On Mon, Nov 5, 2018 at 7:05 PM Masahiro Yamada
>> > <yamada.masahiro@socionext.com> 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@socionext.com>
>> >> ---
>> >>
>> >> 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@google.com>
>> > Tested-by: Nick Desaulniers <ndesaulniers@google.com>
>> >
>> > Would you mind waiting for a tested-by from Stefan, and maybe an ack
>> > from Greg (added to cc)?
>> >
>>
>> Acked-by: Greg Hackmann <ghackmann@google.com>
>
>
> 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.

cheers

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

[Masahiro Yamada]

On Mon, Nov 12, 2018 at 10:05 AM Michael Ellerman <mpe@ellerman.id.au> wrote:
>
> Masahiro Yamada <yamada.masahiro@socionext.com> writes:
> > On Sat, Nov 10, 2018 at 3:35 AM Greg Hackmann <ghackmann@google.com> wrote:
> >>
> >> On 11/09/2018 10:29 AM, Nick Desaulniers wrote:
> >> > On Mon, Nov 5, 2018 at 7:05 PM Masahiro Yamada
> >> > <yamada.masahiro@socionext.com> 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@socionext.com>
> >> >> ---
> >> >>
> >> >> 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@google.com>
> >> > Tested-by: Nick Desaulniers <ndesaulniers@google.com>
> >> >
> >> > Would you mind waiting for a tested-by from Stefan, and maybe an ack
> >> > from Greg (added to cc)?
> >> >
> >>
> >> Acked-by: Greg Hackmann <ghackmann@google.com>
> >
> >
> > 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

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

[Joel Stanley]

On Mon, 12 Nov 2018 at 13:59, Masahiro Yamada
<yamada.masahiro@socionext.com> wrote:
>
> On Mon, Nov 12, 2018 at 10:05 AM Michael Ellerman <mpe@ellerman.id.au> wrote:
> >
> > Masahiro Yamada <yamada.masahiro@socionext.com> writes:
> > > On Sat, Nov 10, 2018 at 3:35 AM Greg Hackmann <ghackmann@google.com> wrote:
> > >>
> > >> On 11/09/2018 10:29 AM, Nick Desaulniers wrote:
> > >> > On Mon, Nov 5, 2018 at 7:05 PM Masahiro Yamada
> > >> > <yamada.masahiro@socionext.com> 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@socionext.com>
> > >> >> ---
> > >> >>
> > >> >> 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@google.com>
> > >> > Tested-by: Nick Desaulniers <ndesaulniers@google.com>
> > >> >
> > >> > Would you mind waiting for a tested-by from Stefan, and maybe an ack
> > >> > from Greg (added to cc)?
> > >> >
> > >>
> > >> Acked-by: Greg Hackmann <ghackmann@google.com>
> > >
> > >
> > > 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, I've done that now.

Cheers,

Joel

Re: [PATCH v2 1/2] kbuild: add -no-integrated-as Clang option unconditionally

[Masahiro Yamada]

On Tue, Nov 6, 2018 at 12:06 PM Masahiro Yamada
<yamada.masahiro@socionext.com> wrote:
>
> We are still a way off the Clang's integrated assembler support for
> the kernel. Hence, -no-integrated-as is mandatory to build the kernel
> with Clang. If you had an ancient version of Clang that does not
> recognize this option, you would not be able to compile the kernel
> anyway.
>
> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
> ---

Applied to linux-kbuild.


>
> Changes in v2:
>   - New patch
>
>  Makefile | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/Makefile b/Makefile
> index 93315eb..da11700 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -497,8 +497,8 @@ CLANG_GCC_TC        := --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 += $(call cc-option, -no-integrated-as)
> -KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
> +KBUILD_CFLAGS += -no-integrated-as
> +KBUILD_AFLAGS += -no-integrated-as
>  endif
>
>  RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register
> --
> 2.7.4
>


-- 
Best Regards
Masahiro Yamada

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

[Masahiro Yamada]

On Tue, Nov 6, 2018 at 12:06 PM Masahiro Yamada
<yamada.masahiro@socionext.com> 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@socionext.com>
> ---


Applied to linux-kbuild.


> 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
>


-- 
Best Regards
Masahiro Yamada