Re: [PATCH] kbuild: use -Oz instead of -Os when using clang

From: Masahiro Yamada
Date: Wed Apr 12 2017 - 16:39:29 EST


2017-04-12 12:38 GMT+09:00 Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>:
> Hi Matthias,
>
>
> 2017-04-11 3:08 GMT+09:00 Matthias Kaehlcke <mka@xxxxxxxxxxxx>:
>> Hi Masahiro,
>>
>> El Fri, Mar 31, 2017 at 02:57:43AM +0900 Masahiro Yamada ha dit:
>>
>>> 2017-03-31 1:41 GMT+09:00 Matthias Kaehlcke <mka@xxxxxxxxxxxx>:
>>> > El Fri, Mar 31, 2017 at 01:03:02AM +0900 Masahiro Yamada ha dit:
>>> >
>>> >> 2017-03-28 10:19 GMT+09:00 Matthias Kaehlcke <mka@xxxxxxxxxxxx>:
>>> >> > This generates smaller resulting object code when compiled with clang.
>>> >> >
>>> >> > Signed-off-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
>>> >> > ---
>>> >> > Makefile | 3 ++-
>>> >> > 1 file changed, 2 insertions(+), 1 deletion(-)
>>> >> >
>>> >> > diff --git a/Makefile b/Makefile
>>> >> > index b2faa9319372..66bcdbf58371 100644
>>> >> > --- a/Makefile
>>> >> > +++ b/Makefile
>>> >> > @@ -638,7 +638,8 @@ KBUILD_CFLAGS += $(call cc-option,-fdata-sections,)
>>> >> > endif
>>> >> >
>>> >> > ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
>>> >> > -KBUILD_CFLAGS += -Os $(call cc-disable-warning,maybe-uninitialized,)
>>> >> > +KBUILD_CFLAGS += $(call cc-option,-Oz,-Os)
>>> >> > +KBUILD_CFLAGS += $(call cc-disable-warning,maybe-uninitialized,)
>>> >> > else
>>> >> > ifdef CONFIG_PROFILE_ALL_BRANCHES
>>> >> > KBUILD_CFLAGS += -O2 $(call cc-disable-warning,maybe-uninitialized,)
>>> >> >
>>> >>
>>> >>
>>> >>
>>> >> This is the same as the following commit in LLVMLinux
>>> >> except Author/Signed-off-by.
>>> >>
>>> >> Who should the authorship really belong to?
>>> >
>>> > (this time without html, sorry for the noise)
>>> >
>>> > It should belong to Behan, I missed to add a 'From' tag, sorry about
>>> > that. Should I resend with the tag or can you fix it when applying the
>>> > patch?
>>>
>>>
>>> No need to re-send it. I can fixup it manually.
>>
>> I couldn't locate this patch in your tree, has it been picked up?
>>
>
>
> I will pick this up shortly. Sorry for the delay.
>


Applied to linux-kbuild/kbuild. Thanks!



--
Best Regards
Masahiro Yamada