Massive performance regression from switching to gcc 4.5

[Taras Glek]

On 06/30/2010 02:26 PM, Basile Starynkevitch wrote:
> On Wed, 2010-06-30 at 14:23 -0700, Taras Glek wrote:
>    
>> I tried 4.5 -O2 and it's actually faster than 4.3 -Os.
>>
>> I am happy that -O2 performance is actually pretty good, but -Os
>> regression is going to hurt on mobile.
>>      
> Did you try gcc-4.5 -flto -Os or gcc-4.5 -flto -O2?
>
> It would be interesting to hear that GCC is able to LTO a program as big
> as Mozilla! And figures (notably RAM, CPU time, wallclock time for
> build) would be interesting.
>    

Both whopr and flto cause gcc to segfault while building Mozilla.


Taras