http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55742
--- Comment #19 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-01-14 20:23:54 UTC --- That wouldn't work, because you would then have the default (non-mv) version, possibly mv version with no target attribute, and then some other mv versions with target attributes. The problem with that is that the first two mangle the same. This means that a non-mv and mv with no target attribute needs to be treated as the same decl (i.e. merged together).