http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59487
--- Comment #4 from rguenther at suse dot de <rguenther at suse dot de> --- "dominiq at lps dot ens.fr" <gcc-bugzi...@gcc.gnu.org> wrote: >http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59487 > >--- Comment #3 from Dominique d'Humieres <dominiq at lps dot ens.fr> >--- >> r202826 was fixed later by the fix for PR58656 (rnflow regression), >> so your bisection converged on a bogus revision. > >OK! I was too focused on the -fwhole-program option. The slowdown after >r202826 >was with/without this option. r203377 fixed the regression without the >option, >but not with it: Still the regression must appear with a different revision. The one you cited has nothing to do with -fwhole-program. Richard. >[Book15] lin/test% /opt/gcc/gcc4.9p-202825/bin/gfortran -Ofast >-fwhole-program >rnflow.f90 >[Book15] lin/test% time a.out > /dev/null >12.843u 0.017s 0:12.86 99.9% 0+0k 0+0io 0pf+0w >[Book15] lin/test% /opt/gcc/gcc4.9p-202825/bin/gfortran -Ofast >rnflow.f90 >[Book15] lin/test% time a.out > /dev/null >12.889u 0.022s 0:12.92 99.8% 0+0k 0+0io 41pf+0w >[Book15] lin/test% /opt/gcc/gcc4.9p-202828/bin/gfortran -Ofast >rnflow.f90 >[Book15] lin/test% time a.out > /dev/null >17.891u 0.019s 0:17.91 99.9% 0+0k 0+0io 0pf+0w >[Book15] lin/test% /opt/gcc/gcc4.9p-202828/bin/gfortran -Ofast >-fwhole-program >rnflow.f90 >[Book15] lin/test% time a.out > /dev/null >17.985u 0.021s 0:18.01 99.9% 0+0k 4+0io 41pf+0w >[Book15] lin/test% /opt/gcc/gcc4.9p-203250/bin/gfortran -Ofast >rnflow.f90 >[Book15] lin/test% time a.out > /dev/null >17.974u 0.020s 0:17.99 100.0% 0+0k 0+0io 0pf+0w >[Book15] lin/test% /opt/gcc/gcc4.9p-203250/bin/gfortran -Ofast >-fwhole-program >rnflow.f90 >[Book15] lin/test% time a.out > /dev/null >18.182u 0.021s 0:18.21 99.9% 0+0k 0+1io 38pf+0w >[Book15] lin/test% /opt/gcc/gcc4.9p-203492/bin/gfortran -Ofast >rnflow.f90 >[Book15] lin/test% time a.out > /dev/null >12.856u 0.018s 0:12.87 99.9% 0+0k 0+0io 0pf+0w >[Book15] lin/test% /opt/gcc/gcc4.9p-203492/bin/gfortran -Ofast >-fwhole-program >rnflow.f90 >[Book15] lin/test% time a.out > /dev/null >18.253u 0.021s 0:18.28 99.9% 0+0k 0+0io 39pf+0w > >AFAICT the usual incantations ('large-function-growth', >'max-inline-insns-auto', or 'builtin-expect-probability') have no >visible >effect on this slowdown with -fwhole-program.