Re: [patch] measurements, numbers about CONFIG_OPTIMIZE_INLINING=y impact

H. Peter Anvin
2009-01-09T19:16:57Z

Richard Guenther wrote:
>>
>> But it's also not inconceivable that gcc adds a -fkernel-inlining or
>> similar that changes the parameters if we ask nicely. I suppose
>> actually such a parameter would be useful for far more programs
>> than the kernel.
>
> I think that the kernel is a perfect target to optimize default -Os behavior for
> (whereas template heavy C++ programs are a target to optimize -O2 for).
> And I think we did a good job in listening to kernel developers if once in
> time they tried to talk to us - GCC 4.3 should be good in compiling the
> kernel with default -Os settings. We, unfortunately, cannot retroactively
> fix old versions that kernel developers happen to like and still use.
>

Unfortunately I think there have been a lot of "we can't talk to them"
on both sides of the kernel-gcc interface, which is incredibly
unfortunate. I personally try to at least observe gcc development,
including monitoring #gcc and knowing enough about gcc internals to
write a (crappy) port, but I can hardly call myself a gcc expert.
Still, I am willing to spend some significant time interfacing with
anyone in the gcc community willing to spend the effort. I think we can
do good stuff.

-hpa