[Bug c/46186] Clang creates code running 1600 times faster than gcc's

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46186

--- Comment #9 from Jonathan Wakely <redi at gcc dot gnu.org> 2010-10-26 
15:28:51 UTC ---
(In reply to comment #8)
> 
> Since the optimization seems to be mostly there in -O3, it's just a matter of
> enabling it in -O2. 

Or if you want all optimisations, it's just a matter of using -O3

Expecting all optimisations to be done below the maximum optimisation level is
... unexpected.