https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68261
--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> --- (In reply to Geir Johansen from comment #4) > (In reply to Andrew Pinski from comment #1) > > Note glibc does provide a memcpy which is optimized for each target via > > ifuncs. What version of glibc are you running. > > 2.11.3 That is a very old release which was released before most of the modern v2/v3 were relased so no wonder you are having performance issues.