http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53073
--- Comment #10 from rguenther at suse dot de <rguenther at suse dot de> 2013-01-29 09:10:25 UTC --- On Mon, 28 Jan 2013, sje at gcc dot gnu.org wrote: > > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53073 > > Steve Ellcey <sje at gcc dot gnu.org> changed: > > What |Removed |Added > ---------------------------------------------------------------------------- > CC| |sje at gcc dot gnu.org > > --- Comment #9 from Steve Ellcey <sje at gcc dot gnu.org> 2013-01-28 18:50:42 > UTC --- > FYI: I reported this issue to SPEC to make sure they were aware of it. > their reply is at: > > http://www.spec.org/cpu2006/Docs/faq.html#Run.05 > > They do not intend to offer alternative sources. So be it. At a last resort we could add a switch that disables just number-of-iteration computations based on undefined behavior. Note that all previous releases of GCC have the same behavior - the knowledge is just not used. Thus such switch would pessimize code further than reverting to previous behavior - nevertheless such switch would be consistent with existing switches like -fno-strict-aliasing or -fno-strict-overflow. Richard.
