lkml.org 
[lkml]   [2018]   [Nov]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH] kbuild: consolidate Clang compiler flags
On Mon, Nov 5, 2018 at 6:10 PM Stefan Agner <stefan@agner.ch> wrote:
>
> On 05.11.2018 03:48, Masahiro Yamada wrote:
> > Add basic options for Clang such as --target, --prefix, --gcc-toolchain,
> > -no-integrated-as to a single variable CLANG_FLAGS.
> >
> > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
> > ---
> >
> > Makefile | 13 ++++++-------
> > 1 file changed, 6 insertions(+), 7 deletions(-)
> >
> > diff --git a/Makefile b/Makefile
> > index 93315eb..58c838a 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)
>
> So this will expand later now, is this ok?
>
> --
> Stefan
>
> > 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 += $(call cc-option, -no-integrated-as)
> > -KBUILD_AFLAGS += $(call cc-option, -no-integrated-as)
> > +CLANG_FLAGS += $(call cc-option, -no-integrated-as)
> > +KBUILD_CFLAGS += $(CLANG_FLAGS)
> > +KBUILD_AFLAGS += $(CLANG_FLAGS)


CLANG_FLAGS is expanded here because KBUILD_CFLAGS and KBUILD_AFLAGS
are defined by using :=

So, it should be OK, but turning CLANG_FLAGS into a simple variable
will be a little more efficient since $(call cc-option, -no-integrated-as)
is evaluated just once.

(Or, this cc-option may not be necessary any longer.)

Will send v2.


Thanks.




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



--
Best Regards
Masahiro Yamada

\
 
 \ /
  Last update: 2018-11-05 10:21    [W:0.045 / U:0.120 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site