http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45879
Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED Resolution| |INVALID --- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> 2010-10-04 04:16:39 UTC --- http://www.opengroup.org/onlinepubs/009695399/functions/strcpy.html says POSIX that overlapping arguments to strcpy is undefined. http://www.aquaphoenix.com/ref/gnu_c_library/libc_61.html says the same thing for glibc. So invalid as overlapping strings causes undefined behavior for strcpy.