On Mon, Jul 29, 2019 at 6:16 PM Masahiro Yamada
<yamada.masahiro@xxxxxxxxxxxxx> wrote:
>
> CLANG_FLAGS is initialized by the following line:
>
> CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE:%-=%))
>
> ..., which is run only when CROSS_COMPILE is set.
>
> Some build targets (bindeb-pkg etc.) recurse to the top Makefile.
>
> When you build the kernel with Clang but without CROSS_COMPILE,
> the same compiler flags such as -no-integrated-as are accumulated
> into CLANG_FLAGS.
>
> If you run 'make CC=clang' and then 'make CC=clang bindeb-pkg',
> Kbuild will recompile everything needlessly due to the build command
> change.
>
> Fix this by correctly initializing CLANG_FLAGS.
>
> Fixes: 238bcbc4e07f ("kbuild: consolidate Clang compiler flags")
> Cc: <stable@xxxxxxxxxxxxxxx> # v4.20+
This should be v5.0+
> Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
> ---
--
Best Regards
Masahiro Yamada
