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Re: Setting -frounding-math by default
On Mon, Mar 9, 2009 at 12:35 AM, Joseph S. Myers
<joseph@codesourcery.com> wrote:
> - Show quoted text -
> On Mon, 9 Mar 2009, Steven Bosscher wrote:
>
>> On Mon, Mar 9, 2009 at 12:24 AM, Joseph S. Myers
>> <joseph@codesourcery.com> wrote:
>> > ?The defaults are deliberate decisions
>> > (and as such the adoption of those decisions cannot meaningfully be
>> > considered a regression: it's not a bug but a feature), but are more
>> > likely to change in the other direction from what you want.
>>
>> I wish the same "not a bug but a feature" measure would be applied to
>> some of the "optimization" regressions (those in Bugzilla and those
>> holding up big cleanups).
>
> I hope we judge optimizations based on whether they seem to improve (or
> not make worse) important benchmarks on important targets rather than the
> impossible standard of not making *any* code worse. ?(And cleanups
> likewise on not making a range of benchmarks worse.)
>
> A particular case made worse may still be a regression, but it could quite
> reasonably be a P4 or P5 regression depending on how much code is
> affected.
It's pretty hard to qualify them as more or less important. So unless
we get completely swamped in P2s like that I'd rather stay to the
current policy. A more reasonable thing would be to downgrade
optimization regressions once they shipped in a stable release, thus
only make optimization regressions against the previous release
series >P3.
Richard.
> --
> - Show quoted text -
> Joseph S. Myers
> joseph@codesourcery.com