https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68261
--- Comment #4 from Geir Johansen <geir at cray dot com> --- (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