Re: [PATCH 03/13] jump label v9: x86 support

From: H. Peter Anvin
Date: Fri Jun 11 2010 - 02:19:38 EST


On 06/10/2010 05:14 AM, Ingo Molnar wrote:
>
> * Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
>
>> On Wed, 2010-06-09 at 17:39 -0400, Jason Baron wrote:
>>> + select HAVE_ARCH_JUMP_LABEL if !CC_OPTIMIZE_FOR_SIZE
>>
>> That deserves a comment somewhere, it basically makes OPTIMIZE_FOR_SIZE
>> useless...
>
> Hm, we need more than a comment for that - distros enable CC_OPTIMIZE_FOR_SIZE
> all the time, for the massive kernel image (and hotpath cache footprint)
> savings. Is this fixable?
>

Actually the current reports from the gcc community is that gcc 4.5.0 +
-Os produces a broken kernel even without asm goto:

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44129

--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.

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