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SubjectRe: -mm merge plans for 2.6.21

On Feb 9 2007 14:04, Andi Kleen wrote:
>Andrew Morton <akpm@linux-foundation.org> writes:
>>
>> As long as nobody takes the address of them (which wouldn't compile today
>> anyway) then the compiler should be able to not allocate store for these.
>
>This would only work for unit-at-a-time compilers (if it works at all,
>i'm not sure), but not older 3.x compilers
>
>> That they're const might help too.
>
>Don't think it does.

GCC 4.1 optimizes both Andrew's and Frederik Deweerdt's ideas
perfectly out. Even if the const was not there in Frederik's example,
gcc seems throw it out with -O2 (judging by `nm` output) since it is
1. static 2. unused. Gcc even gives out a warning that the item is
unused when not marked with const.


Jan
--
ft: http://freshmeat.net/p/chaostables/
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